title: Saturn V

text: NASA planned to use the Saturn C-3 as part of the Earth orbit rendezvous (EOR) method, with at least two or three launches needed for a single lunar mission. However, the MSFC planned an even bigger rocket, the C-4, which would use four F-1 engines in its first stage, an enlarged C-3 second stage, and the S-IVB, a stage with a single J-2 engine, as its third stage. The C-4 would need only two launches to carry out an EOR lunar mission.


title: Saturn V

text: On January 10, 1962, NASA announced plans to build the C-5. The three-stage rocket would consist of the S-IC first stage, with five F-1 engines; the S-II second stage, with five J-2 engines; and the S-IVB third stage, with a single J-2 engine.


title: Saturn V

text: The C-5 would undergo component testing even before the first model was constructed. The S-IVB third stage would be used as the second stage for the C-1B, which would serve both to demonstrate proof of concept and feasibility for the C-5, but would also provide flight data critical to the development of the C-5. Rather than undergoing testing for each major component, the C-5 would be tested in an "all-up" fashion, meaning that the first test flight of the rocket would include complete versions of all three stages. By testing all components at once, far fewer test flights would be required before a crewed launch.


title: Saturn V

text: The C-5 was confirmed as NASA's choice for the Apollo program in early 1962, and was named the Saturn V. The C-1 became the Saturn I and C-1B became Saturn IB. Von Braun headed a team at the MSFC to build a vehicle capable of launching a crewed spacecraft to the Moon. During these revisions, the team rejected the single engine of the V-2's design and moved to a multiple-engine design.


title: Saturn V

text: The Saturn V's final design had several key features. F-1 engines were chosen for the 1st stage, while new liquid hydrogen propulsion system called J-2 for the 2nd and 3rd stage. NASA had finalized its plans to proceed with von Braun's Saturn designs, and the Apollo space program gained speed.


title: Saturn V

text: With the configuration finalized, NASA turned its attention to mission profiles. There was a controversy between using a lunar orbit rendezvous for the lunar module or an Earth orbit rendezvous. The Manned Space Flight Management Council preferred LOR while the President's Scientific Advisory Committee preferred EOR. After a round of studies, James Webb confirmed on November 7 that a lunar orbit rendezvous for the lunar module was chosen. The stages were designed by von Braun's Marshall Space Flight Center in Huntsville, and outside contractors were chosen for the construction: Boeing (S-IC), North American Aviation (S-II), Douglas Aircraft (S-IVB), and IBM (instrument unit).


title: Saturn V

text: Early in the planning process, NASA considered three methods for the Moon mission: Earth orbit rendezvous (EOR), direct ascent, and lunar orbit rendezvous (LOR). A direct ascent configuration would require an extremely large rocket to send a three-man spacecraft to land directly on the lunar surface. An EOR would launch the direct-landing spacecraft in two smaller parts which would combine in Earth orbit. A LOR mission would involve a single rocket launching two spacecraft: a mother ship, and a smaller, two-man landing module which would rendezvous back with the main spacecraft in lunar orbit. The lander would be discarded and the mother ship would return home.


title: Saturn V

text: At first, NASA dismissed LOR as a riskier option, as a space rendezvous had yet to be performed in Earth orbit, much less in lunar orbit. Several NASA officials, including Langley Research Center engineer John Houbolt and NASA Administrator George Low, argued that a lunar orbit rendezvous provided the simplest landing on the Moon with the most cost–efficient launch vehicle, and the best chance to accomplish the lunar landing within the decade. Other NASA officials became convinced, and LOR was then officially selected as the mission configuration for the Apollo program on November 7, 1962. Arthur Rudolph became the project director of the Saturn V rocket program in August 1963. He developed the requirements for the rocket system and the mission plan for the Apollo program. The first Saturn V launch lifted off from Kennedy Space Center and performed flawlessly on November 9, 1967, Rudolph's birthday. He was then assigned as the special assistant to the director of MSFC in May 1968 and subsequently retired from NASA on January 1, 1969. On July 16, 1969, the Saturn V launched Apollo 11, putting man on the Moon.


title: Saturn V

text: The size and payload capacity of the Saturn V dwarfed all other previous rockets successfully flown at that time. With the Apollo spacecraft on top, it stood tall, and, ignoring the fins, was in diameter. Fully fueled, the Saturn V weighed and had a low Earth orbit (LEO) payload capacity originally estimated at , but was designed to send at least to the Moon. Later upgrades increased that capacity; on the final three Apollo lunar missions, it sent up to to the Moon. (It was never used to launch its full LEO payload capability.)


title: Saturn V

text: At a height of , the Saturn V stood taller than the Statue of Liberty from the ground to the torch, and taller than the Elizabeth Tower, which houses Big Ben at the Palace of Westminster. In contrast, the Mercury-Redstone Launch Vehicle used on "Freedom 7", the first crewed American spaceflight, was approximately longer than the S-IVB stage and delivered less sea level thrust () than the Launch Escape System rocket ( sea level thrust) mounted atop the Apollo command module. The Apollo LES fired for a much shorter time than the Mercury-Redstone (3.2 seconds vs. 143.5 seconds).


title: Saturn V

text: The Saturn V was principally designed by the Marshall Space Flight Center in Huntsville, Alabama, although numerous major systems, including propulsion, were designed by subcontractors. It used the powerful F-1 and J-2 rocket engines for propulsion; they shattered the windows of nearby houses when they were tested at Stennis Space Center. Designers decided early on to attempt to use as much technology from the Saturn I program as possible. Consequently, the S-IVB-500 third stage of the Saturn V was based on the S-IVB-200 second stage of the Saturn IB. The instrument unit that controlled the Saturn V shared characteristics with the one carried by the Saturn IB.


title: Saturn V

text: The Saturn V was primarily constructed of aluminum. It was also made of titanium, polyurethane, cork and asbestos. Blueprints and other Saturn V plans are available on microfilm at the Marshall Space Flight Center.


title: Saturn V

text: It consisted of three stages—the S-IC first stage, S-II second stage, and S-IVB third stage—and the instrument unit. All three stages used liquid oxygen (LOX) as the oxidizer. The first stage used RP-1 for fuel, while the second and third stages used liquid hydrogen (LH2). LH2 has a higher specific energy per unit mass than RP-1, which makes it more suitable for higher-energy orbits, such as the trans-lunar injection required for Apollo missions. Conversely, RP-1 offers higher energy density per unit volume and higher thrust than LH2, which makes it more suitable for reducing aerodynamic drag and gravity losses in the early stages of launch. If the first stage had used LH2, the volume required would have been more than three times greater, which is aerodynamically infeasible. The upper stages also used small solid-propellant ullage motors that helped to separate the stages during the launch, and to ensure that the liquid propellants were in a proper position to be drawn into the pumps.


title: Saturn V

text: The S-IC was built by the Boeing Company at the Michoud Assembly Facility, New Orleans, where the Space Shuttle external tanks would later be built by Lockheed Martin. Most of its mass at launch was propellant: RP-1 fuel with liquid oxygen as the oxidizer. It was tall and in diameter, and provided over of thrust. The S-IC stage had a dry mass of about ; when fully fueled at launch, it had a total mass of . It was powered by five Rocketdyne F-1 engines arrayed in a quincunx. The center engine was held in a fixed position, while the four outer engines could be hydraulically turned with gimbals to steer the rocket. In flight, the center engine was turned off about 26 seconds earlier than the outboard engines to limit acceleration. During launch, the S-IC fired its engines for 168 seconds (ignition occurred about 8.9 seconds before liftoff) and at engine cutoff, the vehicle was at an altitude of about , was downrange about , and was moving about .


title: Saturn V

text: The S-II was built by North American Aviation at Seal Beach, California. Using liquid hydrogen and liquid oxygen, it had five Rocketdyne J-2 engines in a similar arrangement to the S-IC, and also used the outer engines for control. The S-II was tall with a diameter of , identical to the S-IC, and thus was the largest cryogenic stage until the launch of the Space Shuttle in 1981. The S-II had a dry mass of about ; when fully fueled, it weighed . The second stage accelerated the Saturn V through the upper atmosphere with of thrust in a vacuum.


title: Saturn V

text: When loaded, significantly more than 90 percent of the mass of the stage was propellant; however, the ultra-lightweight design had led to two failures in structural testing. Instead of having an intertank structure to separate the two fuel tanks as was done in the S-IC, the S-II used a common bulkhead that was constructed from both the top of the LOX tank and bottom of the LH2 tank. It consisted of two aluminum sheets separated by a honeycomb structure made of phenolic resin. This bulkhead had to insulate against the temperature difference between the two tanks. The use of a common bulkhead saved by both eliminating one bulkhead and reducing the stage's length. Like the S-IC, the S-II was transported from its manufacturing plant to Cape Kennedy by sea.


title: Saturn V

text: The S-IVB was built by the Douglas Aircraft Company at Huntington Beach, California. It had one J-2 engine and used the same fuel as the S-II. The S-IVB used a common bulkhead to separate the two tanks. It was tall with a diameter of and was also designed with high mass efficiency, though not quite as aggressively as the S-II. The S-IVB had a dry mass of about and, fully fueled, weighed about .


title: Saturn V

text: The S-IVB was the only rocket stage of the Saturn V small enough to be transported by the cargo plane Aero Spacelines Pregnant Guppy.


title: Saturn V

text: For lunar missions it was fired twice: first for Earth orbit insertion after second stage cutoff, and then for translunar injection (TLI).


title: Saturn V

text: The instrument unit was built by IBM and was placed on top of the third stage. It was constructed at the Space Systems Center in Huntsville, Alabama. This computer controlled the operations of the rocket from just before liftoff until the S-IVB was discarded. It included guidance and telemetry systems for the rocket. By measuring the acceleration and vehicle attitude, it could calculate the position and velocity of the rocket and correct for any deviations.


title: Saturn V

text: After the construction and ground testing of each stage was completed, it was shipped to the Kennedy Space Center. The first two stages were so massive that the only way to transport them was by barge. The S-IC, constructed in New Orleans, was transported down the Mississippi River to the Gulf of Mexico.


title: Saturn V

text: After rounding Florida, the stages were transported up the Intra-Coastal Waterway to the Vehicle Assembly Building (originally called the Vertical Assembly Building). This was essentially the same route which would be used later to ship Space Shuttle external tanks. The S-II was constructed in California and traveled to Florida via the Panama Canal. The third stage and Instrument Unit was carried by the Aero Spacelines Pregnant Guppy and Super Guppy, but could also have been carried by barge if warranted.


title: Saturn V

text: Upon arrival at the Vertical Assembly Building, each stage was inspected in a horizontal position before being oriented vertically. NASA also constructed large spool-shaped structures that could be used in place of stages if a particular stage was delayed. These spools had the same height and mass and contained the same electrical connections as the actual stages.


title: Saturn V

text: NASA stacked (assembled) the Saturn V on a Mobile Launcher, which consisted of a Launch Umbilical Tower with nine swing arms (including the crew access arm), a "hammerhead" crane, and a water suppression system which was activated prior to launch. After assembly was completed, the entire stack was moved from the Vehicle Assembly Building (VAB) to the launch pad using the Crawler Transporter (CT). Built by the Marion Power Shovel Company (and later used for transporting the smaller and lighter Space Shuttle), the CT ran on four double-tracked treads, each with 57 "shoes". Each shoe weighed . This transporter was also required to keep the rocket level as it traveled the to the launch site, especially at the 3 percent grade encountered at the launch pad. The CT also carried the Mobile Service Structure (MSS), which allowed technicians access to the rocket until eight hours before launch, when it was moved to the "halfway" point on the Crawlerway (the junction between the VAB and the two launch pads).


title: Saturn V

text: From 1964 until 1973, $6.417 billion (equivalent to $ in ) in total was appropriated for the Research and Development and flights of the Saturn V, with the maximum being in 1966 with $1.2 billion (equivalent to $ in ). That same year, NASA received its largest total budget of $4.5 billion, about 0.5 percent of the gross domestic product (GDP) of the United States at that time.


title: Saturn V

text: Two main reasons for the cancellation of the last three Apollo missions were the heavy investments in Saturn V and the ever-increasing costs of the Vietnam War to the U.S. in money and resources. In the time frame from 1969 to 1971 the cost of launching a Saturn V Apollo mission was between $185,000,000 to $189,000,000, of which $110 million were used for the production of the vehicle (equivalent to $–$ in ).


title: Saturn V

text: The Saturn V carried all Apollo lunar missions, which were launched from Launch Complex 39 at the John F. Kennedy Space Center in Florida. After the rocket cleared the launch tower, flight control transferred to Mission Control at the Johnson Space Center in Houston, Texas. An average mission used the rocket for a total of just 20 minutes. Although Apollo 6 experienced three engine failures, and Apollo 13 one engine shutdown, the onboard computers were able to compensate by burning the remaining engines longer to achieve parking orbit.


title: Saturn V

text: In the event of an abort requiring the destruction of the rocket, the range safety officer would remotely shut down the engines and after several seconds send another command for the shaped explosive charges attached to the outer surfaces of the rocket to detonate. These would make cuts in fuel and oxidizer tanks to disperse the fuel quickly and to minimize mixing. The pause between these actions would give time for the crew to escape via the Launch Escape Tower or (in the later stages of the flight) the propulsion system of the Service module. A third command, "safe", was used after the S-IVB stage reached orbit to irreversibly deactivate the self-destruct system. The system was inactive as long as the rocket was still on the launch pad.


title: Saturn V

text: The first stage burned for about 2 minutes and 41 seconds, lifting the rocket to an altitude of and a speed of and burning of propellant.


title: Saturn V

text: At 8.9 seconds before launch, the first stage ignition sequence started. The center engine ignited first, followed by opposing outboard pairs at 300-millisecond intervals to reduce the structural loads on the rocket. When thrust had been confirmed by the onboard computers, the rocket was "soft-released" in two stages: first, the hold-down arms released the rocket, and second, as the rocket began to accelerate upwards, it was slowed by tapered metal pins pulled through holes for half a second.


title: Saturn V

text: Once the rocket had lifted off, it could not safely settle back down onto the pad if the engines failed. The astronauts considered this one of the tensest moments in riding the Saturn V, for if the rocket did fail to lift off after release they had a low chance of survival given the large amounts of propellant. To improve safety, the Saturn Emergency Detection System (EDS) inhibited engine shutdown for the first 30 seconds of flight. If all three stages were to explode simultaneously on the launch pad, an unlikely event, the Saturn V had a total explosive yield of 543 tons of TNT or 0.543 kilotons (2,271,912,000,000 J or 155,143 lbs of weight loss), which is 0.222 kt for the first stage, 0.263 kt for the second stage and 0.068 kt for the third stage. (See Saturn V Instrument Unit)


title: Saturn V

text: It took about 12 seconds for the rocket to clear the tower. During this time, it yawed 1.25 degrees away from the tower to ensure adequate clearance despite adverse winds; this yaw, although small, can be seen in launch photos taken from the east or west. At an altitude of the rocket rolled to the correct flight azimuth and then gradually pitched down until 38 seconds after second stage ignition. This pitch program was set according to the prevailing winds during the launch month.


title: Saturn V

text: The four outboard engines also tilted toward the outside so that in the event of a premature outboard engine shutdown the remaining engines would thrust through the rocket's center of mass. The Saturn V reached at over in altitude. Much of the early portion of the flight was spent gaining altitude, with the required velocity coming later. The Saturn V broke the sound barrier at just over 1 minute at an altitude of between . At this point, shock collars, or condensation clouds, would form around the bottom of the command module and around the top of the second stage.


title: Saturn V

text: At about 80 seconds, the rocket experienced maximum dynamic pressure (max q). The dynamic pressure on a rocket varies with air density and the square of relative velocity. Although velocity continues to increase, air density decreases so quickly with altitude that dynamic pressure falls below max q.


title: Saturn V

text: The propellant in just the S-IC made up about three-quarters of Saturn V's entire launch mass, and it was consumed at . Newton's second law of motion states that force is equal to mass multiplied by acceleration, or equivalently that acceleration is equal to force divided by mass, so as the mass decreased (and the force increased somewhat), acceleration rose. Including gravity, launch acceleration was only  "g", i.e., the astronauts felt  "g" while the rocket accelerated vertically at  "g". As the rocket rapidly lost mass, total acceleration including gravity increased to nearly 4 "g" at T+135 seconds. At this point, the inboard (center) engine was shut down to prevent acceleration from increasing beyond 4 "g".


title: Saturn V

text: When oxidizer or fuel depletion was sensed in the suction assemblies, the remaining four outboard engines were shut down. First stage separation occurred a little less than one second after this to allow for F-1 thrust tail-off. Eight small solid fuel separation motors backed the S-IC from the rest of the vehicle at an altitude of about . The first stage continued ballistically to an altitude of about and then fell in the Atlantic Ocean about downrange.


title: Saturn V

text: The engine shutdown procedure was changed for the launch of Skylab to avoid damage to the Apollo Telescope Mount. Rather than shutting down all four outboard engines at once, they were shut down two at a time with a delay to reduce peak acceleration further.


title: Saturn V

text: After S-IC separation, the S-II second stage burned for 6 minutes and propelled the craft to and , close to orbital velocity.


title: Saturn V

text: For the first two uncrewed launches, eight solid-fuel ullage motors ignited for four seconds to accelerate the S-II stage, followed by the ignition of the five J-2 engines. For the first seven crewed Apollo missions only four ullage motors were used on the S-II, and they were eliminated for the final four launches. About 30 seconds after first stage separation, the interstage ring dropped from the second stage. This was done with an inertially fixed attitude—orientation around its center of gravity—so that the interstage, only from the outboard J-2 engines, would fall cleanly without hitting them, as the interstage could have potentially damaged two of the J-2 engines if it was attached to the S-IC. Shortly after interstage separation the Launch Escape System was also jettisoned.


title: Saturn V

text: About 38 seconds after the second stage ignition the Saturn V switched from a preprogrammed trajectory to a "closed loop" or Iterative Guidance Mode. The instrument unit now computed in real time the most fuel-efficient trajectory toward its target orbit. If the instrument unit failed, the crew could switch control of the Saturn to the command module's computer, take manual control, or abort the flight.


title: Saturn V

text: About 90 seconds before the second stage cutoff, the center engine shut down to reduce longitudinal pogo oscillations. At around this time, the LOX flow rate decreased, changing the mix ratio of the two propellants and ensuring that there would be as little propellant as possible left in the tanks at the end of second stage flight. This was done at a predetermined delta-v.


title: Saturn V

text: Five level sensors in the bottom of each S-II propellant tank were armed during S-II flight, allowing any two to trigger S-II cutoff and staging when they were uncovered. One second after the second stage cut off it separated and several seconds later the third stage ignited. Solid fuel retro-rockets mounted on the interstage at the top of the S-II fired to back it away from the S-IVB. The S-II impacted about from the launch site.


title: Saturn V

text: On the Apollo 13 mission, the inboard engine suffered from major pogo oscillation, resulting in an early automatic cutoff. To ensure sufficient velocity was reached, the remaining four engines were kept active for longer than planned. A pogo suppressor was fitted to later Apollo missions to avoid this, though the early engine 5 cutoff remained to reduce g-forces.


title: Saturn V

text: Unlike the two-plane separation of the S-IC and S-II, the S-II and S-IVB stages separated with a single step. Although it was constructed as part of the third stage, the interstage remained attached to the second stage. The third stage did not use much fuel to get into LEO (Low Earth Orbit), because the second stage had done most of the job.


title: Saturn V

text: During Apollo 11, a typical lunar mission, the third stage burned for about 2.5 minutes until first cutoff at 11 minutes 40 seconds. At this point it was downrange and in a parking orbit at an altitude of and velocity of . The third stage remained attached to the spacecraft while it orbited the Earth one and a half times while astronauts and mission controllers prepared for translunar injection (TLI).


title: Saturn V

text: This parking orbit was quite low by Earth orbit standards, and it would have been short-lived due to aerodynamic drag. For perspective, the current ISS orbits at an altitude of roughly , and requires a reboost roughly once a month. This was not a problem on a lunar mission because of the short stay in the parking orbit. The S-IVB also continued to thrust at a low level by venting gaseous hydrogen, to keep propellants settled in their tanks and prevent gaseous cavities from forming in propellant feed lines. This venting also maintained safe pressures as liquid hydrogen boiled off in the fuel tank. This venting thrust easily exceeded aerodynamic drag.


title: Saturn V

text: For the final three Apollo flights, the temporary parking orbit was even lower (approximately ), to increase payload for these missions. The Apollo 9 Earth orbit mission was launched into the nominal orbit consistent with Apollo 11, but the spacecraft were able to use their own engines to raise the perigee high enough to sustain the 10-day mission. The Skylab was launched into a quite different orbit, with a perigee which sustained it for six years, and also a higher inclination to the equator (50 degrees versus 32.5 degrees for Apollo).


title: Saturn V

text: On Apollo 11, TLI came at 2 hours and 44 minutes after launch. The S-IVB burned for almost six minutes, giving the spacecraft a velocity close to the Earth's escape velocity of . This gave an energy-efficient transfer to lunar orbit, with the Moon helping to capture the spacecraft with a minimum of CSM fuel consumption.


title: Saturn V

text: About 40 minutes after TLI, the Apollo command and service module (CSM) separated from the third stage, turned 180 degrees, and docked with the Lunar Module (LM) that rode below the CSM during launch. The CSM and LM separated from the spent third stage 50 minutes later, in a maneuver known as transposition, docking, and extraction.


title: Saturn V

text: If it were to remain on the same trajectory as the spacecraft, the S-IVB could have presented a collision hazard, so its remaining propellants were vented and the auxiliary propulsion system fired to move it away. For lunar missions before Apollo 13, the S-IVB was directed toward the Moon's trailing edge in its orbit so that the Moon would slingshot it beyond earth escape velocity and into solar orbit. From Apollo 13 onwards, controllers directed the S-IVB to hit the Moon. Seismometers left behind by previous missions detected the impacts, and the information helped map the internal structure of the Moon.


title: Saturn V

text: In 1965, the Apollo Applications Program (AAP) was created to look into science missions that could be performed using Apollo hardware. Much of the planning centered on the idea of a space station. Wernher von Braun's earlier (1964) plans employed a "wet workshop" concept, with a spent S-II Saturn V second stage being launched into orbit and outfitted in space. The next year AAP studied a smaller station using the Saturn IB second stage. By 1969, Apollo funding cuts eliminated the possibility of procuring more Apollo hardware and forced the cancellation of some later Moon landing flights. This freed up at least one Saturn V, allowing the wet workshop to be replaced with the "dry workshop" concept: the station (now known as Skylab) would be built on the ground from a surplus Saturn IB second stage and launched atop the first two live stages of a Saturn V. A backup station, constructed from a Saturn V third stage, was built and is now on display at the National Air and Space Museum.


title: Saturn V

text: Skylab was the only launch not directly related to the Apollo lunar landing program. The only significant changes to the Saturn V from the Apollo configurations involved some modification to the S-II to act as the terminal stage for inserting the Skylab payload into Earth orbit, and to vent excess propellant after engine cutoff so the spent stage would not rupture in orbit. The S-II remained in orbit for almost two years, and made an uncontrolled re-entry on January 11, 1975.


title: Saturn V

text: Three crews lived aboard Skylab from May 25, 1973, to February 8, 1974. Skylab remained in orbit until July 11, 1979.


title: Saturn V

text: After Apollo, the Saturn V was planned to be the prime launch vehicle for Prospector to be launched to the Moon. Prospector was a proposed robotic rover, similar to the Soviet Lunokhod rovers Lunokhod 1 and Lunokhod 2, the Voyager Mars probes, and a scaled-up version of the Voyager interplanetary probes. It was also to have been the launch vehicle for the nuclear rocket stage RIFT test program and for some versions of the later NERVA. All of these planned uses of the Saturn V were cancelled, with cost being a major factor. Edgar Cortright, who had been the director of NASA Langley, stated decades later that "JPL never liked the big approach. They always argued against it. I probably was the leading proponent in using the Saturn V, and I lost. Probably very wise that I lost."


title: Saturn V

text: The canceled second production run of Saturn Vs would very likely have used the F-1A engine in its first stage, providing a substantial performance boost. Other likely changes would have been the removal of the fins (which turned out to provide little benefit when compared to their weight), a stretched S-IC first stage to support the more powerful F-1As, and uprated J-2s or an M-1 for the upper stages.


title: Saturn V

text: A number of alternate Saturn vehicles were proposed based on the Saturn V, ranging from the Saturn INT-20 with an S-IVB stage and interstage mounted directly onto an S-IC stage, through to the Saturn V-23(L) which would not only have five F-1 engines in the first stage, but also four strap-on boosters with two F-1 engines each, giving a total of thirteen F-1 engines firing at launch.


title: Saturn V

text: Lack of a second Saturn V production run killed this plan and left the United States without a super heavy-lift launch vehicle. Some in the U.S. space community came to lament this situation, as continued production could have allowed the International Space Station, using a "Skylab" or "Mir" configuration with both U.S. and Russian docking ports, to be lifted with just a handful of launches. The Saturn-Shuttle concept also could have eliminated the Space Shuttle Solid Rocket Boosters that ultimately precipitated the "Challenger" accident in 1986.


title: Saturn V

text: U.S. proposals for a rocket larger than the Saturn V from the late 1950s through the early 1980s were generally called Nova. Over thirty different large rocket proposals carried the Nova name, but none were developed.


title: Saturn V

text: Wernher von Braun and others also had plans for a rocket that would have featured eight F-1 engines in its first stage, like the Saturn C-8, allowing a direct ascent flight to the Moon. Other plans for the Saturn V called for using a Centaur as an upper stage or adding strap-on boosters. These enhancements would have enabled the launch of large robotic spacecraft to the outer planets or the sending of astronauts to Mars. Other Saturn V derivatives analyzed included the Saturn MLV family of "Modified Launch Vehicles", which would have almost doubled the payload lift capability of the standard Saturn V and were intended for use in a proposed mission to Mars by 1980.


title: Saturn V

text: In 1968, Boeing studied another Saturn-V derivative, the Saturn C-5N, which included a nuclear thermal rocket engine for the third stage of the vehicle. The Saturn C-5N would carry a considerably greater payload for interplanetary spaceflight. Work on the nuclear engines, along with all Saturn V ELVs, ended in 1973.


title: Saturn V

text: The Comet HLLV was a massive heavy lift launch vehicle designed for the First Lunar Outpost program, which was in the design phase from 1992 to 1993 under the Space Exploration Initiative. It was a Saturn V derived launch vehicle with over twice the payload capability and would have relied completely on existing technology. All of the engines were modernized versions of their Apollo counterparts and the fuel tanks would be stretched. Its main goal was to support the First Lunar Outpost program and future crewed Mars missions. It was designed to be as cheap and easy to operate as possible.


title: Saturn V

text: In 2006, as part of the proposed Constellation program, NASA unveiled plans to construct two Shuttle Derived Launch Vehicles, the Ares I and Ares V, which would use some existing Space Shuttle and Saturn V hardware and infrastructure. The two rockets were intended to increase safety by specializing each vehicle for different tasks, Ares I for crew launches and Ares V for cargo launches. The original design of the heavy-lift Ares V, named in homage to the Saturn V, was in height and featured a core stage based on the Space Shuttle External Tank, with a diameter of . It was to be powered by five RS-25s and two five-segment Space Shuttle Solid Rocket Boosters (SRBs). As the design evolved, the RS-25 engines were replaced with five RS-68 engines, the same engines used on the Delta IV. The switch from the RS-25 to the RS-68 was intended to reduce cost, as the latter was cheaper, simpler to manufacture, and more powerful than the RS-25, though the lower efficiency of the RS-68 required an increase in core stage diameter to , the same diameter as the Saturn V's S-IC and S-II stages.


title: Saturn V

text: In 2008, NASA again redesigned the Ares V, lengthening the core stage, adding a sixth RS-68 engine, and increasing the SRBs to 5.5 segments each. This vehicle would have been tall and would have produced a total thrust of approximately at liftoff, more than the Saturn V or the Soviet Energia, but less than the Soviet N-1. Projected to place approximately into orbit, the Ares V would have surpassed the Saturn V in payload capability. An upper stage, the Earth Departure Stage, would have utilized a more advanced version of the J-2 engine, the J-2X. Ares V would have placed the Altair lunar landing vehicle into low Earth orbit. An Orion crew vehicle launched on Ares I would have docked with Altair, and the Earth Departure Stage would then send the combined stack to the Moon.


title: Saturn V

text: After the cancellation of the Constellation program – and hence Ares I and Ares V – NASA announced the Space Launch System (SLS) heavy-lift launch vehicle for beyond low Earth orbit space exploration. The SLS, similar to the original Ares V concept, is powered by four RS-25 engines and two five-segment SRBs. Its Block 1 configuration can lift approximately to LEO. The Block 1B configuration will add the Exploration Upper Stage, powered by four RL10 engines, to increase payload capacity. An eventual Block 2 variant will upgrade to advanced boosters, increasing LEO payload to at least .


title: Saturn V

text: One proposal for advanced boosters would use a derivative of the Saturn V's F-1, the F-1B, and increase SLS payload to around to LEO. The F-1B is to have better specific impulse and be cheaper than the F-1, with a simplified combustion chamber and fewer engine parts, while producing of thrust at sea level, an increase over the approximate achieved by the mature Apollo 15 F-1 engine,


title: Saturn V

text: On September 3, 2002, astronomer Bill Yeung discovered a suspected asteroid, which was given the discovery designation J002E3. It appeared to be in orbit around the Earth, and was soon discovered from spectral analysis to be covered in white titanium dioxide, which was a major constituent of the paint used on the Saturn V. Calculation of orbital parameters led to tentative identification as being the Apollo 12 S-IVB stage. Mission controllers had planned to send Apollo 12's S-IVB into solar orbit after separation from the Apollo spacecraft, but it is believed the burn lasted too long, and hence did not send it close enough to the Moon, so it remained in a barely stable orbit around the Earth and Moon. In 1971, through a series of gravitational perturbations, it is believed to have entered in a solar orbit and then returned into weakly captured Earth orbit 31 years later. It left Earth orbit again in June 2003.


title: ZIP Code

text: A ZIP Code is a postal code used by the United States Postal Service (USPS). Introduced on July 1, 1963, the basic format consisted of five digits. In 1983, an extended ZIP+4 code was introduced; it included the five digits of the ZIP Code, followed by a hyphen and four digits that designated a more specific location.


title: ZIP Code

text: The term "ZIP" is an acronym for Zone Improvement Plan; it was chosen to suggest that the mail travels more efficiently and quickly (zipping along) when senders use the code in the postal address. The term "ZIP Code" was originally registered as a service mark by the USPS; its registration expired in 1997.


title: ZIP Code

text: The early history and context of postal codes began with postal district/zone numbers. The United States Post Office Department (USPOD) implemented postal zones for many large cities in 1943.


title: ZIP Code

text: By the early 1960s, a more organized system was needed, and non-mandatory five-digit ZIP Codes were introduced nationwide on July 1, 1963. The USPOD issued its "Publication 59: Abbreviations for Use with ZIP Code" on October 1, 1963, with the list of two-letter state abbreviations which are generally written with both letters capitalized. An earlier list, publicized in June 1963, had proposed capitalized abbreviations ranging from two to five letters. According to "Publication 59", the two-letter standard was "based on a maximum 23-position line, because this has been found to be the most universally acceptable line capacity basis for major addressing systems", which would be exceeded by a long city name combined with a multi-letter state abbreviation, such as "Sacramento, Calif." along with the ZIP Code. The abbreviations have remained unchanged, with the exception of Nebraska, which was changed from NB to NE in 1969 at the request of the Canadian Post Office Department, to avoid confusion with New Brunswick.


title: ZIP Code

text: Robert Moon is considered the father of the ZIP Code; he submitted his proposal in 1944 while working as a postal inspector. The phrase "zone improvement plan" is credited to D. Jamison Cain, a Postal Service executive. The post office credits Moon with only the first three digits of the ZIP Code, which describe the sectional center facility (SCF) or "sec center". An SCF is a central mail processing facility with those three digits. The fourth and fifth digits, which give a more precise locale within the SCF, were proposed by Henry Bentley Hahn, Sr.


title: ZIP Code

text: The SCF sorts mail to all post offices with those first three digits in their ZIP Codes. The mail is sorted according to the final two digits of the ZIP Code and sent to the corresponding post offices in the early morning. Sectional centers do not deliver mail and are not open to the public (although the building may include a post office that is open to the public), and most of their employees work the night shift. Items of mail picked up at post offices are sent to their own SCFs in the afternoon, where the mail is sorted overnight. In the case of large cities, the last two digits as assigned generally coincided with the older postal zone number.


title: ZIP Code

text: In 1967, these became mandatory for second- and third-class bulk mailers, and the system was soon adopted generally. The United States Post Office used a cartoon character, which it called Mr. ZIP, to promote the use of the ZIP Code. The name "Mr. ZIP" was coined by D. Jamison Cain. Mr. ZIP was often depicted with a legend such as "USE ZIP CODE" in the selvage of panes of postage stamps or on the covers of booklet panes of stamps. Mr. ZIP was featured prominently alongside musical group "The Swingin' Six" in a variety show that the post office used to explain the importance of using ZIP codes.


title: ZIP Code

text: In 1971, Elmira (NY) "Star-Gazette" reporter Dick Baumbach found out the White House was not using a ZIP Code on its envelopes. Herb Klein, special assistant to President Nixon, responded by saying the next printing of envelopes would include the ZIP Code.


title: ZIP Code

text: In 1983, the U.S. Postal Service introduced an expanded ZIP Code system that it called "ZIP+4", often called "plus-four codes", "add-on codes", or "add-ons". A ZIP+4 Code uses the basic five-digit code plus four additional digits to identify a geographic segment within the five-digit delivery area, such as a city block, a group of apartments, an individual high-volume receiver of mail, a post office box, or any other unit that could use an extra identifier to aid in efficient mail sorting and delivery. However, the new format was not adopted universally by the public; it eventually became obsolete with modern technology. In general, mail is read by a multiline optical character reader (MLOCR) that almost instantly determines the correct ZIP+4 Code from the address—along with the even more specific delivery point—and sprays an Intelligent Mail barcode (IMb) on the face of the mail piece that corresponds to 11 digits—nine for the ZIP+4 Code and two for the delivery point.


title: ZIP Code

text: For post office boxes, the general (but not invariable) rule is that each box has its own ZIP+4 code. The add-on code is often one of the following: the last four digits of the box number (e.g. PO Box 107050, Albany, NY 12201-7050), zero plus the last three digits of the box number (e.g., PO Box 17727, Eagle River, AK 99577-0727), or, if the box number consists of fewer than four digits, enough zeros are attached to the front of the box number to produce a four-digit number (e.g., PO Box 77, Juneau, AK 99750-0077). However, there is no uniform rule, so the ZIP+4 Code must be looked up individually for each box (e.g. using the USPS's official ZIP Code Lookup tool, and being sure to enter just city and state, not the 5-digit ZIP).


title: ZIP Code

text: The ZIP Code is often translated into an Intelligent Mail barcode that is printed on the mailpiece to make it easier for automated machines to sort. A barcode can be printed by the sender (some word-processing programs such as WordPerfect include the feature), but this is not recommended, as the address-to-ZIP lookup tables can be significantly out of date.


title: ZIP Code

text: Customers who send bulk mail can get a discount on postage if they have printed the barcode themselves and have presorted the mail. This requires more than just a simple font; mailing lists must be standardized with up-to-date Coding Accuracy Support System (CASS)-certified software that adds and verifies a full, correct ZIP+4 Code and an additional two digits representing the exact delivery point. Furthermore, mail must be sorted in a specific manner to an 11-digit code with at least 150 mailpieces for each qualifying ZIP Code and must be accompanied by documentation confirming this. These steps are usually done with PAVE-certified software that also prints the barcoded address labels and the barcoded sack or tray tags.


title: ZIP Code

text: The assignment of delivery point digits (the 10th and 11th digits) is intended to ensure that every single mailable point in the country has its own 12-digit number. The delivery-point digits are calculated based on the primary or secondary number of the address. The USPS publishes the rules for calculating the delivery point in a document called the CASS Technical Guide.


title: ZIP Code

text: ZIP Codes designate delivery points within the United States (and its territories). There are generally no ZIP Codes for deliveries to other countries, except for the independent countries of the Federated States of Micronesia, the Republic of the Marshall Islands, and the Republic of Palau, each of which is integrated into the U.S. postal system under a Compact of Free Association. Another exception is ZIP Codes used for overseas stations of USA armed forces.


title: ZIP Code

text: Mail to U.S. diplomatic missions overseas is addressed as if it were addressed to a street address in Washington, D.C. The four-digit diplomatic pouch number is used as a building number, while the city in which the embassy or consulate is located is combined with the word "Place" to form a street name. Each mission uses a ZIP+4 Code consisting of 20521 and the diplomatic pouch number.


title: ZIP Code

text: For example, the mailing address of U.S. Embassy in New Delhi, India as per India's 6-digit Postal Index Number (PIN) code system is:


title: ZIP Code

text: However, individuals posted at diplomatic missions overseas are now assigned a Diplomatic Post Office address and unique box number. The ZIP Code identifies the diplomatic mission destination and is different from the diplomatic pouch number in the example above. While delivered through the pouch system, mail to such addresses are not considered "Diplomatic Pouch" materials, and as such must adhere to the mailing regulations of the host country. An example address is:


title: ZIP Code

text: Unique ZIP Codes are used for governmental agencies, universities, businesses, or buildings receiving sufficiently high volumes of mail to justify the assignment to them of exclusive ZIP Codes. Government examples include 20505 for the Central Intelligence Agency in Washington, D.C., and 81009 for the Federal Citizen Information Center of the U.S. General Services Administration (GSA) in Pueblo, Colorado. An example of a university-specific ZIP Code is 21252, which serves Towson University. An example of a private address unique ZIP Code is that assigned to the headquarters of Walmart (72716). They may also be assigned to a single program, such as the Postal Service's Operation Santa Claus program, under which children are invited to write to Santa Claus at "North Pole 88888".


title: ZIP Code

text: An example of a PO box-only ZIP Code is 22313, used for boxes at the main post office in Alexandria, Virginia, including those used by the United States Patent and Trademark Office. In the area surrounding that post office, home and business mail delivery addresses use ZIP Code 22314, a standard ZIP Code.


title: ZIP Code

text: ZIP Codes are numbered with the first digit representing a certain group of U.S. states, the second and third digits together representing a region in that group (or perhaps a large city) and the fourth and fifth digits representing a group of delivery addresses within that region. The main town in a region (if applicable) often gets the first ZIP Codes for that region; afterward, the numerical order often follows the alphabetical order. Because ZIP Codes are intended for efficient postal delivery, there are unusual cases where a ZIP Code crosses state boundaries, such as a military facility spanning multiple states or remote areas of one state most easily serviced from a bordering state. For example, ZIP Code 42223 serves Fort Campbell, which spans Christian County, Kentucky, and Montgomery County, Tennessee, and ZIP Code 97635 includes portions of Lake County, Oregon, and Modoc County, California.


title: ZIP Code

text: In general, the first three digits designate a sectional center facility, the mail sorting and distribution center for an area. A sectional center facility may have more than one three-digit code assigned to it. For example, the Northern Virginia sectional center facility in Merrifield is assigned codes 220, 221, 222, and 223. In some cases, a sectional center facility may serve an area in an adjacent state, usually due to the lack of a proper location for a center in that region. For example, 739 in Oklahoma is assigned to Amarillo, Texas; 297 in South Carolina is assigned to Charlotte, North Carolina; 865 in Arizona is assigned to Albuquerque, New Mexico; and 961 in California to Reno, Nevada.


title: ZIP Code

text: Many of the lowest ZIP Codes, which begin with '0', are in the New England region. Also in the '0' region are New Jersey (non-contiguous with the remainder of the '0' area), Puerto Rico, the U.S. Virgin Islands, and APO/FPO military addresses for personnel stationed in Europe, Africa, Southwest Asia, and onboard vessels based in the waters adjoining those lands. The lowest ZIP Code is in Holtsville, New York (00501, a ZIP Code exclusively for the U.S. Internal Revenue Service center there). Other low ZIP Codes are 00601 for Adjuntas, Puerto Rico; 01001 for Agawam, Massachusetts, and the ZIP Codes 01002 and 01003 for Amherst, Massachusetts; 01002 is used for mail in town, while 01003 is reserved for the University of Massachusetts Amherst. Until 2001, there were six ZIP Codes lower than 00501 that were numbered from 00210 to 00215 (located in Portsmouth, New Hampshire) and were used by the Diversity Immigrant Visa program to receive applications from non-U.S. citizens.


title: ZIP Code

text: The numbers increase southward along the East Coast, such as 02115 (Boston), 10001 (New York City), 19103 (Philadelphia), 21201 (Baltimore), 20008 (Washington, D.C.), 30303 (Atlanta), and 33130 (Miami) (these are only examples, as each of these cities contains several ZIP Codes in the same range). From there, the numbers increase heading westward and northward east of the Mississippi River, southward west of the Mississippi River, and northward on the West Coast. For example, 40202 is in Louisville, 50309 in Des Moines, 60601 in Chicago, 63101 in St. Louis, 77036 in Houston, 80202 in Denver, 94111 in San Francisco, 98101 in Seattle, and 99950 in Ketchikan, Alaska (the highest ZIP Code).


title: ZIP Code

text: The second and third digits represent the sectional center facility (SCF) (e.g. 477xx = Vanderburgh County, Indiana), and the fourth and fifth digits represent the area of the city (if in a metropolitan area), or a village/town (outside metro areas), e.g. 47722 (4=Indiana, 77=Vanderburgh County, 22=University of Evansville area). When a sectional center facility's area crosses state lines, that facility is assigned separate three-digit prefixes for the states that it serves.


title: ZIP Code

text: In some urban areas, like 462 for Marion County, Indiana, the three-digit prefix will often exist in one county, while, in rural and most suburban areas, the prefix will exist in multiple counties; for example, the neighboring 476 prefix is found in part or entirely in six counties: Gibson, Pike, Posey, Spencer, Vanderburgh, and Warrick. In some cases, an urban county may have more than one prefix. This is the case with Allen (467, 468), Lake (464, 463), St. Joseph (465, 466), and Vanderburgh (476, 477) counties. Cities like Chicago, Houston, Los Angeles, and New York City have multiple prefixes within their city limits. In some cases, these may be served from the same SCF, such as in San Diego County, California, where the three-digit prefixes 919 and 920 are used for suburban and rural communities, and 921 for the city of San Diego itself, although all three are processed through the same SCF facility.


title: ZIP Code

text: Despite the geographic derivation of most ZIP Codes, the codes themselves do not represent geographic regions; in general, they correspond to address groups or delivery routes. As a consequence, ZIP Code "areas" can overlap, be subsets of each other, or be artificial constructs with no geographic area (such as 095 for mail to the Navy, which is not geographically fixed). In similar fashion, in areas without regular postal routes (rural route areas) or no mail delivery (undeveloped areas), ZIP Codes are not assigned or are based on sparse delivery routes, and hence the boundary between ZIP Code areas is undefined. For example, some residents in or near Haubstadt, Indiana, which has the ZIP Code 47639, have mailing addresses with 47648, the ZIP Code for neighboring Fort Branch, Indiana, while others living in or near Fort Branch have addresses with 47639. Many rural counties have similar logistical inconsistencies caused by the aforementioned sparse delivery routes, often known as Rural Routes or by some other similar designation.


title: ZIP Code

text: Almost all U.S. government agencies in and around the capital are assigned ZIP Codes starting with 20200 to 20599, which are Washington, D.C., ZIP Codes, even if they are not located in Washington itself. While the White House itself is located in ZIP Code 20006, it has the ZIP Code 20500. The Nuclear Regulatory Commission is located in Rockville, Maryland, at ZIP Code 20852, but has been assigned by the Postal Service the address "Washington, DC 20555".


title: ZIP Code

text: In similar manner, the ZIP Code for the Metropolitan Washington Airports Authority, a federally chartered independent authority, is 20001–6000, even though the physical address of the Authority's office, "1 Aviation Circle", is in Arlington, Virginia.


title: ZIP Code

text: One current exception to this rule is the United States Patent and Trademark Office (USPTO). When the USPTO was located in the Crystal City neighborhood in Arlington, Virginia, it was assigned by the Postal Service the address "Washington, DC 20231" despite being physically located in ZIP Code 22202. However, the USPTO now uses ZIP Codes assigned to its current locations in Alexandria, Virginia. The patents side of the USPTO uses a PO box assigned the ZIP+4 code of 22313-1450 for all postal communications. The trademarks side of the USPTO uses the same ZIP+4 code for most of its mail, but the office of the Commissioner for Trademarks has its own PO box with the ZIP+4 code of 22313–1451, and some offices within that part of the USPTO use the 22314 ZIP Code.


title: ZIP Code

text: In rare circumstances, a locality is assigned a ZIP Code that does not match the rest of the state. In even rarer cases a ZIP Code may cross state lines. Usually, this occurs when the locality is so isolated that it is most conveniently served from a sectional center in another state. Examples:


title: ZIP Code

text: A ZIP Code's address and the city name written on the same line do not necessarily mean that address is within the boundaries of that city. The Postal Service designates one "preferred" place name for each ZIP Code. This may be an incorporated town or city, a subentity of a large city or an unincorporated census-designated place, or a small unincorporated community. Additional place names may be recognized as "acceptable" for a certain ZIP Code. Still, others are deemed not acceptable, and if used may result in a delay in mail delivery.


title: ZIP Code

text: "Preferred" place names are generally the city or town in which the address is located. However, for many cities that have incorporated since ZIP Codes were introduced, the city name is not the "preferred" place name. Many databases automatically assign the "preferred" place name for a ZIP Code, without regard to any "acceptable" place names. For example, Centennial, Colorado is divided among seven ZIP Codes assigned to Aurora, Englewood, or Littleton as its "preferred" place names; none of these seven ZIP Codes carries "Centennial" as a preferred name, and in the ZIP Code directory, Centennial addresses are listed under those three cities. Since it is acceptable to write "Centennial" in conjunction with any of the seven ZIP Codes, one can write "Centennial" in an address in Aurora, Englewood, or Littleton, as long as it is in one of the shared ZIP Codes.


title: ZIP Code

text: "Acceptable" place names are usually added to a ZIP Code in cases where the ZIP Code boundaries divide them between two or more cities, as in the case of Centennial. However, in many cases, only the "preferred" name can be used, even when many addresses in the ZIP Code are in another city. People sometimes must use the name of a post office rather than their own city.


title: ZIP Code

text: One extreme example is ZIP Code 85254; it was assigned the place name Scottsdale, Arizona, because it is served by the Scottsdale post office, but 85% of its territory is inside the city limits of neighboring Phoenix. Another notorious example is an entire neighborhood in the City of Los Angeles known as Beverly Glen, which is served by Beverly Hills Post Office. Its residents prefer the more glamorous Beverly Hills address and 90210 ZIP Code, but this regularly causes problems with emergency response when dispatchers have to sort out whether a given home in 90210 is in Los Angeles or Beverly Hills.


title: ZIP Code

text: Similarly, Missouri City, Texas, straddles Harris and Fort Bend counties. The portion within Harris County is within the ZIP Code 77071, which must use the city name of Houston instead of Missouri City. At the same time, a small portion of the city of Houston is in Fort Bend County in the ZIP Code 77489, and residents there must use the name "Missouri City" for their address even though they are in Houston.


title: ZIP Code

text: This also occurs in some rural areas where portions of one town have their mail delivered to other post offices. For example, while most of the town of Goffstown, New Hampshire is in ZIP Code 03045, some sections of town are in the ZIP Code area for the neighboring city of Manchester with ZIP Code 03102. Only the "preferred" name of Manchester is allowed in ZIP Code 03102, so residents of parts of Goffstown must list their address as being in Manchester.


title: ZIP Code

text: This phenomenon is repeated across the country. The previously mentioned Englewood, Colorado is an inner-ring suburb that was built out by the 1960s. Its post office served the area that is now the high-growth southern tier of the Denver metropolitan area, and ZIP Codes in this area were assigned Englewood as their "preferred" place name. A business community as large as downtown Denver has grown in this area, with headquarters for many internationally recognized corporations. These companies indicate Englewood as their location (the "preferred" postal place name), although they are located in other cities. As a result, there are really two Englewoods – the city, small and with a largely working-class residential population, and, a number of miles away, the postal Englewood, a vast suburban area of upscale subdivisions and office parks that have nothing to do with the city of Englewood yet share a split identity with it solely because of ZIP Codes. People who say they live or work in Englewood and identify closely with it may rarely enter the city. In Indiana, the ZIP Code for a town usually indicates the ZIP Code for its corresponding township, as nearly all of Indiana's small town post offices have rural routes.


title: ZIP Code

text: "Acceptable" place names also come into play in areas where citizens identify more strongly with a particular urban center than their own municipality. For example, Allegheny County, Pennsylvania, has 130 distinct municipalities, yet many of the county's residents, and even some residents of adjacent counties, commonly use Pittsburgh, Pennsylvania as their postal address. On the opposite end of the spectrum, in some urban areas, neighborhood names may be acceptable even though they have no legal standing, such as La Jolla, California, which is the "preferred" place name for ZIP Code 92037, despite the fact that La Jolla is a district of San Diego, California and not a separate legal entity. This ZIP Code is also in the 919/920 sequence used by San Diego County's suburban and rural areas, not in the 921 sequence used in the remainder of the City of San Diego, even though La Jolla has always been part of San Diego.


title: ZIP Code

text: Many ZIP Codes are for villages, census-designated places, portions of cities, or other entities that are not municipalities. For example, ZIP Code 03750 is for Etna, New Hampshire, but Etna is not a city or town; it is a village district in the town of Hanover, which itself is assigned the ZIP Code 03755. Another example is ZIP Code 08043, which corresponds to the census-designated place of Kirkwood, New Jersey, but serves the entirety of Voorhees Township. This is also the case in LaGrange, New York, a portion of which is served by the 12603 ZIP Code based in the neighboring town of Poughkeepsie. The rest of LaGrange is served by the LaGrangeville Post Office. LaGrangeville is itself not a town at all, but a section of LaGrange. Willow Grove, Pennsylvania, served by the 19090 ZIP Code, is a village that straddles the border of Upper Moreland Township and Abington Township, and that post office also serves a small portion of Upper Dublin Township. Furthermore, non-municipal place names may also share ZIP Codes with municipal place names. For example, West Windsor Township, New Jersey, is commonly referred to in most mailing databases as Princeton Junction, a census-designated place within West Windsor. Silver Spring, Maryland, (20815, 20901–20912) is neither a city nor a town, but simply the common name for an unincorporated area consisting of a large part of the lower southern portion of Montgomery County.


title: ZIP Code

text: Postal designations for place names become "de facto" locations for their addresses, and as a result, it is difficult to convince residents and businesses that they are located in another city or town different from the "preferred" place name associated with their ZIP Codes. Because of issues of confusion and lack of identity, some cities, such as Signal Hill, California (an enclave located entirely inside the separate city of Long Beach), have successfully petitioned the Postal Service to change ZIP Code boundaries or create new ZIP Codes so their cities become the "preferred" place name for addresses within the ZIP Code.


title: ZIP Code

text: Postal designation confusion may have financial implications for local governments because mail volume is one factor used by the U.S. Census Bureau to estimate population changes between decennial census enumerations. Sometimes local officials in a community that is not the "preferred" place name for a ZIP Code but is an "acceptable" place name will advise residents to always use the name of the community, because if the census estimate of that town's population is low they may receive fewer funds that are computed based on population. A typical example is Paddock Lake, Wisconsin, whose "preferred" place name is Salem. Paddock Lake is incorporated as a village within the town of Salem, even though there are more people in the village of Paddock Lake than there are in the unincorporated parts of the town of Salem. Further confusion is caused because Silver Lake, Wisconsin, which is also a village in the town of Salem and is of similar size and status to Paddock Lake, has its own ZIP Code and post office.


title: ZIP Code

text: In another case, the U.S. Federal Communications Commission (FCC) denied a radio station, WNNX, a move from Anniston, Alabama into the Atlanta market, which asked for a change of its city of license to its intended new studio location in Sandy Springs, Georgia, largely because it was not a city (until municipal incorporation in late 2005), despite being the seventh-largest place in the state by population. The FCC uses community support rather than full-market support to tabulate applications, and cited the specific use of "Atlanta" in letters of support from local organizations, even though the USPS forced them to use Atlanta for 30328 until well after incorporation took effect; the station then chose to license to College Park instead and associated technical changes for the application to meet acceptability, with studios in Sandy Springs. Currently "Sandy Springs" is only "acceptable", despite none of 30328 being in Atlanta, or anywhere else outside the Sandy Springs city limit. This even applies to the ZIP Code used only for PO boxes at the Sandy Springs main post office.


title: ZIP Code

text: Because ZIP Codes and their associated place names can ignore county lines, problems may occur where street addresses are based on quadrant location within a county. For example, the area served by 30339 straddles the Cobb County–Fulton County line in Georgia. The Cobb County portion of this area includes Vinings in the southeast of that county; the Fulton County portion lies within the city limits of Atlanta. Every street address in Vinings is labeled SE, and has a house number on the Cobb County grid (according to the distance from the town square in the county seat of Marietta). However, because the USPS demands the use of Atlanta, Vinings addresses are written such that they appear to be in southeast Atlanta, instead of in the opposite (northwest metro Atlanta) side.


title: ZIP Code

text: Like area codes, ZIP Codes are sometimes divided and changed, especially when a rural area becomes suburban. Typically, the new codes become effective once announced, and a grace period (e.g., one year) is provided in which the new and old codes are used concurrently so that postal patrons in the affected area can notify correspondents, order new stationery, etc.


title: ZIP Code

text: In rapidly growing communities, it is sometimes necessary to open a new sectional center facility, which must then be allocated its own three-digit ZIP-code prefix or prefixes. Such allocation can be done in various ways. For example, when a new sectional center facility was opened at Dulles Airport in Virginia, the prefix 201 was allocated to that facility; therefore, for all post offices to be served by that sectional center facility the ZIP Code changed from an old code beginning with 220 or 221 to a new code or codes beginning with 201. However, when a new sectional center facility was opened to serve Montgomery County, Maryland, no new prefix was assigned. Instead, ZIP Codes in the 207 and 208 ranges, which had previously been assigned alphabetically, were reshuffled so that 207xx ZIP Codes in the county was changed to 208xx codes, while 208xx codes outside that county were changed to 207xx codes. Because Silver Spring (whose postal area includes Wheaton) has its own prefix, 209, there was no need to apply the reshuffling to Silver Spring; instead, all mail going to 209xx ZIP Codes was simply rerouted to the new sectional center facility.


title: ZIP Code

text: On the other hand, depopulation may cause a post office to close and its associated ZIP Code to be deallocated. For example, Centralia, Pennsylvania's ZIP Code, 17927, was retired in 2002, and ZIP Codes for Onoville (14764), Quaker Bridge (14771) and Red House (14773) in New York were prevented from going into use in 1964 in preparation for the Kinzua Dam's completion.


title: ZIP Code

text: Elkins Park, Pennsylvania, was originally issued the 19117 ZIP Code, although it lies in Montgomery County, Pennsylvania. Because of the 191 prefix, which is found only in Philadelphia apart from that lone exception, auto insurance companies charged higher city premiums to residents of that suburban location. For that reason, residents petitioned the USPS for a 190-prefix ZIP Code, which is common to the inner-ring Pennsylvania suburbs of that city, and, after several attempts that were initially disapproved by the USPS, Elkins Park was finally reassigned to the 19027 ZIP Code.


title: ZIP Code

text: ZIP Codes also change when postal boundaries are realigned. For example, concurrent with the above-noted change in Montgomery County, Maryland, and under pressure from the then-mayor of Washington, D.C., Marion Barry, the USPS realigned the postal boundaries between Washington, D.C. and Maryland to match the boundary. Previously, many inner suburbs, such as Bethesda and Takoma Park, Oxon Hill, Temple Hills, Suitland, and Capitol Heights had been in the Washington, D.C., postal area. As a result of the change, ZIP Codes in Maryland beginning with 200 were changed to new ZIP Codes beginning with 207, 208, or 209, depending on their location, and ZIP Codes straddling the D.C.–Maryland line were split. For example, 20016 (Bethesda) became 20816, while the Maryland portion of 20012 (Takoma Park) became 20912.


title: ZIP Code

text: Delivery services other than the USPS, such as FedEx, United Parcel Service, and DHL, require a ZIP Code for optimal internal routing of a package.


title: ZIP Code

text: , there are 41,702 ZIP Codes in the United States. ZIP Codes are used not only for tracking of mail, but also in gathering geographical statistics in the United States. The U.S. Census Bureau calculates approximate boundaries of ZIP Codes areas, which it calls ZIP Code Tabulation Areas (ZCTAs). Statistical census data is then provided for these approximate areas. The geographic data provided for these areas includes the latitude and longitude of the center-point of the ZCTAs. There are approximately 32,000 ZCTAs. The reason that there is not one ZCTA for every ZIP Code is that PO Boxes are excluded, since only populated areas are included in the Census data. The Census Bureau provides many statistical data sets for ZIP Codes, but does not keep up-to-date datasets of all ZCTAs. Complete datasets providing a similar approximate geographic extent are commercially available. ZIP Codes are inherently discrete or "point-based" data, as they are assigned only at the point of delivery, not for the spaces in between the delivery points. The United States Census Bureau then interpolates this discrete data set to create polygons, or areal features representing the approximate extent of the ZIP Code to use for mapping and data presentation. ZCTAs are not to be confused with ZIP Codes, and they are not updated as frequently as ZIP Codes. However, for many research and planning purposes, they are very useful and can be used with ZIP Code data.


title: ZIP Code

text: The data is often used in direct mail marketing campaigns in a process called ZIP-code marketing. Point-of-sale cashiers sometimes ask consumers for their home ZIP Codes. Besides providing purchasing-pattern data useful in determining the location of new business establishments, retailers can use directories to correlate this ZIP Code with the name on a credit card to obtain a consumer's full address and telephone number. ZIP-Coded data are also used in analyzing geographic factors in risk, an insurance and banking industry practice pejoratively known as redlining. This can cause problems, "e.g.", expensive insurance, for people living near a town with a high crime rate and sharing its ZIP Code, while they live in a relatively crime-free town. (See Elkins Park, Pennsylvania, above.)


title: ZIP Code

text: ZIP Codes may not currently be used to identify existing legislative districts. Although the website of the United States House of Representatives has a "Find Your Representative" feature that looks up congressional districts based on ZIP Codes alone, it often returns multiple districts corresponding to a single ZIP Code. This is because different parts of one ZIP Code can be in different districts. One proposal to eliminate the possibility of extreme partisan gerrymandering calls on using ZIP Codes as the basic units for redistricting.


title: ZIP Code

text: ZIP Code data is an integral part of dealer / store locator software on many websites, especially brick-and-click websites. This software processes a user-input ZIP Code and returns a list of store or business locations, usually in the order of increasing distance from the center of the input ZIP Code. As the ZIP Code system is confined to the U.S. Postal network, websites that require ZIP Codes cannot register customers outside the United States. Many sites will purchase postal code data of other countries or make allowances in cases where the ZIP Code is not recognized.


title: ZIP Code

text: ZIP Codes are regularly used on the Internet to provide a location in situations where an exact address is not necessary (or desirable) but the user's municipality or general location is needed. Examples (in addition to the store locator example listed above) include weather forecasts, television listings, local news, and online dating (most general-purpose sites, by default, search within a specified radius of a given ZIP Code, based on other users' entered ZIP Codes).


title: ZIP Code

text: ZIP Codes are used in credit card authorization, specifically Address Verification System (AVS). When a merchant collects the entire address, the ZIP Code is an important part of AVS. In some cases, the ZIP Code is the only thing used for AVS, specifically where collecting a signature, or other information is infeasible, such as pay at the pump or vending machines.


title: Vitamin C

text: Vitamin C (also known as ascorbic acid and ascorbate) is a water-soluble vitamin found in citrus and other fruits and vegetables, also sold as a dietary supplement and as a topical 'serum' ingredient to treat melasma (dark pigment spots) and wrinkles on the face. It is used to prevent and treat scurvy. Vitamin C is an essential nutrient involved in the repair of tissue, the formation of collagen, and the enzymatic production of certain neurotransmitters. It is required for the functioning of several enzymes and is important for immune system function. It also functions as an antioxidant. Most animals are able to synthesize their own vitamin C. However, apes (including humans) and monkeys (but not all primates), most bats, some rodents, and certain other animals must acquire it from dietary sources.


title: Vitamin C

text: There is some evidence that regular use of supplements may reduce the duration of the common cold, but it does not appear to prevent infection. It is unclear whether supplementation affects the risk of cancer, cardiovascular disease, or dementia. It may be taken by mouth or by injection.


title: Vitamin C

text: Vitamin C is generally well tolerated. Large doses may cause gastrointestinal discomfort, headache, trouble sleeping, and flushing of the skin. Normal doses are safe during pregnancy. The United States Institute of Medicine recommends against taking large doses.


title: Vitamin C

text: Vitamin C was discovered in 1912, isolated in 1928, and, in 1933, was the first vitamin to be chemically produced. It is on the World Health Organization's List of Essential Medicines. Vitamin C is available as an inexpensive generic and over-the-counter medication. Partly for its discovery, Albert Szent-Györgyi and Walter Norman Haworth were awarded the 1937 Nobel Prizes in Physiology and Medicine and Chemistry, respectively. Foods containing vitamin C include citrus fruits, kiwifruit, guava, broccoli, Brussels sprouts, bell peppers, potatoes, and strawberries. Prolonged storage or cooking may reduce vitaminC content in foods.


title: Vitamin C

text: Vitamin C is an essential nutrient for certain animals including humans. The term "vitamin C" encompasses several vitamers that have vitamin C activity in animals. Ascorbate salts such as sodium ascorbate and calcium ascorbate are used in some dietary supplements. These release ascorbate upon digestion. Ascorbate and ascorbic acid are both naturally present in the body, since the forms interconvert according to pH. Oxidized forms of the molecule such as dehydroascorbic acid are converted back to ascorbic acid by reducing agents.


title: Vitamin C

text: Vitamin C functions as a cofactor in many enzymatic reactions in animals (including humans) that mediate a variety of essential biological functions, including wound healing and collagen synthesis. In humans, vitamin C deficiency leads to impaired collagen synthesis, contributing to the more severe symptoms of scurvy. Another biochemical role of vitamin C is to act as an antioxidant (a reducing agent) by donating electrons to various enzymatic and non-enzymatic reactions. Doing so converts vitamin C to an oxidized state - either as semidehydroascorbic acid or dehydroascorbic acid. These compounds can be restored to a reduced state by glutathione and NADPH-dependent enzymatic mechanisms.


title: Vitamin C

text: In plants, vitamin C is a substrate for ascorbate peroxidase. This enzyme utilizes ascorbate to neutralize excess hydrogen peroxide (HO) by converting it to water (HO) and oxygen.


title: Vitamin C

text: Vitamin C blood serum levels are considered saturated at levels (1.1 mg/dL), achieved by consuming amounts which are at, or above, the Recommended Dietary Allowance, while adequate levels are defined as . Hypovitaminosis in the case of vitamin C is defined as and deficiency occurs at . For those 20 years of age or above, data from the U.S. 2003-04 NHANES survey showed mean and median serum concentrations of 49.0 and 54.4μmol/L, respectively. The percent of people reported as deficient was 7.1%.


title: Vitamin C

text: Scurvy is a disease resulting from a deficiency of vitamin C. Without this vitamin, collagen made by the body is too unstable to perform its function and several other enzymes in the body do not operate correctly. Scurvy is characterized by spots on and bleeding under the skin, spongy gums, 'corkscrew' hair growth, and poor wound healing. The skin lesions are most abundant on the thighs and legs, and a person with the ailment looks pale, feels depressed, and is partially immobilized. In advanced scurvy there are open, suppurating wounds, loss of teeth, bone abnormalities and, eventually, death.


title: Vitamin C

text: Notable human dietary studies of experimentally induced scurvy were conducted on conscientious objectors during World War II in Britain and on Iowa state prisoners in the late 1960s to the 1980s. Men in the prison study developed the first signs of scurvy about four weeks after starting the vitamin C-free diet, whereas in the earlier British study, six to eight months were required, possibly due to the pre-loading of this group with a 70 mg/day supplement for six weeks before the scorbutic diet was fed. Men in both studies had blood levels of ascorbic acid too low to be accurately measured by the time they developed signs of scurvy. These studies both reported that all obvious symptoms of scurvy could be completely reversed by supplementation of only 10 mg a day.


title: Vitamin C

text: People in sepsis or septic shock may have micronutrient deficiencies, including low levels of vitamin C.


title: Vitamin C

text: Vitamin C has a definitive role in treating scurvy, which is a disease caused by vitaminC deficiency. Beyond that, a role for vitaminC as prevention or treatment for various diseases is disputed, with reviews reporting conflicting results. A 2012 Cochrane review reported no effect of vitaminC supplementation on overall mortality. It is on the World Health Organization's List of Essential Medicines.


title: Vitamin C

text: The disease scurvy is caused by vitaminC deficiency and can be prevented and treated with vitaminC-containing foods or dietary supplements. It takes at least a month of little to no vitaminC before symptoms occur. Early symptoms are malaise and lethargy, progressing to shortness of breath, bone pain, bleeding gums, susceptibility to bruising, poor wound healing, and finally fever, convulsions and eventual death. Until quite late in the disease the damage is reversible, as healthy collagen replaces the defective collagen with vitaminC repletion. Treatment can be oral supplementation of the vitamin or by intramuscular or intravenous injection. Scurvy was known to Hippocrates in the classical era. The disease was shown to be prevented by citrus fruits in an early controlled trial by a Royal Navy surgeon, James Lind, in 1747, on board HMS Salisbury. From 1796 onward, lemon juice was issued to all Royal Navy crewmen.


title: Vitamin C

text: Research on vitaminC in the common cold has been divided into effects on prevention, duration, and severity. A Cochrane review which looked at at least 200 mg/day concluded that vitaminC taken on a regular basis was not effective in prevention of the common cold. Restricting analysis to trials that used at least 1000 mg/day also saw no prevention benefit. However, taking vitaminC on a regular basis did reduce the average duration by 8% in adults and 14% in children, and also reduced severity of colds. A subset of trials in adults reported that supplementation reduced the incidence of colds by half in marathon runners, skiers, or soldiers in subarctic conditions. Another subset of trials looked at therapeutic use, meaning that vitaminC was not started unless the people started to feel the beginnings of a cold. In these, vitaminC did not affect duration or severity. An earlier review stated that vitaminC did not prevent colds, did reduce duration, did not reduce severity. The authors of the Cochrane review concluded that:


title: Vitamin C

text: Vitamin C distributes readily in high concentrations into immune cells, has antimicrobial and natural killer cell activities, promotes lymphocyte proliferation, and is consumed quickly during infections, effects suggesting a prominent role in immune system regulation. The European Food Safety Authority found a cause and effect relationship exists between the dietary intake of vitamin C and functioning of a normal immune system in adults and in children under three years of age.


title: Vitamin C

text: Several studies found Vitamin C to have specific antiviral effects in which it inactivates the RNA or DNA of viruses or in the assembly of the virus.


title: Vitamin C

text: According to ClinicalTrials.gov, as of early 2021 there were 50 completed or ongoing COVID-19 clinical trials including vitamin C as a treatment. A meta-analysis of six published trials was published in October 2021. Treatments were either oral or intravenous. Dose ranged from 50 mg/kg/day to 24 g/day. Reported outcomes were mortality, hospitalization duration, intensive care duration and need for ventilation. From the Conclusion: "The present meta-analysis showed that administration of vitamin C did not have any effect on major health outcomes in COVID infected patients, in comparison to either placebo/standard therapy. Sub-group analysis also revealed that irrespective of its dosage, route of administration and disease severity, it didn't have discernible benefit in such patients. Hence, larger prospective randomized trials are needed in order to evaluate the effect of isolated vitamin C administration, separately for both vitamin C replete and deplete individuals."


title: Vitamin C

text: During March through July 2020, vitamin C was the subject of more US FDA warning letters than any other ingredient for prevention and/or treatment of COVID-19.


title: Vitamin C

text: As of April 2021, the National Institutes of Health (NIH) "COVID-19 Treatment Guidelines" stated that "there are insufficient data to recommend either for or against the use of vitaminC for the prevention or treatment of COVID-19."


title: Vitamin C

text: There is no evidence that vitamin C supplementation reduces the risk of lung cancer in healthy people or those at high risk due to smoking or asbestos exposure. A second meta-analysis found no effect on the risk of prostate cancer. Two meta-analyses evaluated the effect of vitamin C supplementation on the risk of colorectal cancer. One found a weak association between vitamin C consumption and reduced risk, and the other found no effect from supplementation. A 2011 meta-analysis failed to find support for the prevention of breast cancer with vitamin C supplementation, but a second study concluded that vitamin C may be associated with increased survival in those already diagnosed. A 2015 meta-analysis showed no antitumor effect nor improvement in quality-of-life measures from high-dose vitamin C. This review included trials of oral and intravenous vitamin C.


title: Vitamin C

text: In 2017, an independent study evaluating 15,445 participants found no evidence to show vitamin C decreases the risk cardiovascular disease. These results supported one 2013 review which found no evidence that antioxidant vitamin supplementation reduces the risk of myocardial infarction, stroke, cardiovascular mortality, or all-cause mortality (it did not provide subset analysis for trials that just used vitamin C).


title: Vitamin C

text: However, another 2013 review found an association between higher circulating vitamin C levels or dietary vitamin C and a lower risk of stroke.


title: Vitamin C

text: A 2014 review found a positive effect of vitamin C on endothelial dysfunction when taken at doses greater than 500 mg per day. The endothelium is a layer of cells that line the interior surface of blood vessels.


title: Vitamin C

text: A 2017 systematic review found lower vitamin C concentrations in people with cognitive impairment, including Alzheimer's disease and dementia, compared to people with normal cognition. The cognitive testing, however, relied on the Mini-Mental State Examination, which is only a general test of cognition, indicating an overall low quality of research assessing the potential importance of vitamin C on cognition in normal and impaired people. A review of nutrient status in people with Alzheimer's disease reported low plasma vitamin C, but also low blood levels of folate, vitamin B, and vitamin E.


title: Vitamin C

text: One of the causes of iron-deficiency anemia is reduced absorption of iron. Iron absorption can be enhanced though ingestion of vitamin C alongside iron-containing food or supplements. The instability of vitamin C during cooking and/or storage limits the number of foods suitable for this. Vitamin C helps to keep iron in the reduced ferrous state, which is more soluble and more easily absorbed.


title: Vitamin C

text: Studies examining the effects of vitamin C intake on the risk of Alzheimer's disease have reached conflicting conclusions. Maintaining a healthy dietary intake is probably more important than supplementation for achieving any potential benefit. A 2010 review found no role for vitamin C supplementation in the treatment of rheumatoid arthritis. Vitamin C supplementation does not prevent or slow the progression of age-related cataract. A systematic review reported that low intake and low serum concentration was associated with greater progression of periodontal disease.


title: Vitamin C

text: Vitamin C is a water-soluble vitamin, with dietary excesses not absorbed, and excesses in the blood rapidly excreted in the urine, so it exhibits remarkably low acute toxicity. More than two to three grams may cause indigestion, particularly when taken on an empty stomach. However, taking vitamin C in the form of sodium ascorbate and calcium ascorbate may minimize this effect. Other symptoms reported for large doses include nausea, abdominal cramps and diarrhea. These effects are attributed to the osmotic effect of unabsorbed vitamin C passing through the intestine. In theory, high vitamin C intake may cause excessive absorption of iron. A summary of reviews of supplementation in healthy subjects did not report this problem, but left as untested the possibility that individuals with hereditary hemochromatosis might be adversely affected.


title: Vitamin C

text: There is a longstanding belief among the mainstream medical community that vitamin C increases risk of kidney stones. "Reports of kidney stone formation associated with excess ascorbic acid intake are limited to individuals with renal disease". Reviews state that "data from epidemiological studies do not support an association between excess ascorbic acid intake and kidney stone formation in apparently healthy individuals", although one large, multi-year trial did report a nearly two-fold increase in kidney stones in men who regularly consumed a vitamin C supplement.


title: Vitamin C

text: In 2000, the chapter on Vitamin C in the North American Dietary Reference Intake was updated to give the Recommended Dietary Allowance (RDA) as 90 milligrams per day for adult men, 75 mg/day for adult women, and setting a Tolerable upper intake level (UL) for adults of 2,000 mg/day. The table (right) shows RDAs for the United States and Canada for children, and for pregnant and lactating women, as well as the ULs for adults.


title: Vitamin C

text: For the European Union, the EFSA set higher recommendations for adults, and also for children: 20 mg/day for ages 1–3, 30 mg/day for ages 4–6, 45 mg/day for ages 7–10, 70 mg/day for ages 11–14, 100 mg/day for males ages 15–17, 90 mg/day for females ages 15–17. For pregnancy 100 mg/day; for lactation 155 mg/day.


title: Vitamin C

text: India, on the other hand, has set recommendations much lower: 40 mg/day for ages 1 through adult, 60 mg/day for pregnancy, and 80 mg/day for lactation. Clearly, there is not consensus among countries.


title: Vitamin C

text: Cigarette smokers and people exposed to secondhand smoke have lower serum vitamin C levels than nonsmokers. The thinking is that inhalation of smoke causes oxidative damage, depleting this antioxidant vitamin. The U.S. Institute of Medicine estimated that smokers need 35 mg more vitamin C per day than nonsmokers, but did not formally establish a higher RDA for smokers. One meta-analysis showed an inverse relationship between vitamin C intake and lung cancer, although it concluded that more research is needed to confirm this observation.


title: Vitamin C

text: The U.S. National Center for Health Statistics conducts biannual National Health and Nutrition Examination Survey (NHANES) to assess the health and nutritional status of adults and children in the United States. Some results are reported as What We Eat In America. The 2013-2014 survey reported that for adults ages 20 years and older, men consumed on average 83.3 mg/d and women 75.1 mg/d. This means that half the women and more than half the men are not consuming the RDA for vitamin C. The same survey stated that about 30% of adults reported they consumed a vitamin C dietary supplement or a multi-vitamin/mineral supplement that included vitamin C, and that for these people total consumption was between 300 and 400 mg/d.


title: Vitamin C

text: In 2000, the Institute of Medicine of the U.S. National Academy of Sciences set a Tolerable upper intake level (UL) for adults of 2,000 mg/day. The amount was chosen because human trials had reported diarrhea and other gastrointestinal disturbances at intakes of greater than 3,000 mg/day. This was the Lowest-Observed-Adverse-Effect Level (LOAEL), meaning that other adverse effects were observed at even higher intakes. ULs are progressively lower for younger and younger children. In 2006, the European Food Safety Authority (EFSA) also pointed out the disturbances at that dose level, but reached the conclusion that there was not sufficient evidence to set a UL for vitamin C, as did the Japan National Institute of Health and Nutrition in 2010.


title: Vitamin C

text: For U.S. food and dietary supplement labeling purposes, the amount in a serving is expressed as a percent of Daily Value (%DV). For vitamin C labeling purposes, 100% of the Daily Value was 60 mg, but as of May 27, 2016, it was revised to 90 mg to bring it into agreement with the RDA. A table of the old and new adult daily values is provided at Reference Daily Intake.


title: Vitamin C

text: European Union regulations require that labels declare energy, protein, fat, saturated fat, carbohydrates, sugars, and salt. Voluntary nutrients may be shown if present in significant amounts. Instead of Daily Values, amounts are shown as percent of Reference Intakes (RIs). For vitamin C, 100% RI was set at 80 mg in 2011.


title: Vitamin C

text: Although also present in other foods, the richest natural sources of vitamin C are fruits and vegetables. The vitamin is the most widely taken dietary supplement.


title: Vitamin C

text: While plant foods are generally a good source of vitamin C, the amount in foods of plant origin depends on the variety of the plant, soil condition, climate where it grew, length of time since it was picked, storage conditions, and method of preparation. The following table is approximate and shows the relative abundance in different raw plant sources. Generally, cooking reduces the amount of vitamin C. As some plants were analyzed fresh while others were dried (thus, artificially increasing concentration of individual constituents such as vitamin C), the data are subject to potential variation and difficulties for comparison. The amount is given in milligrams per 100 grams of the edible portion of the fruit or vegetable:


title: Vitamin C

text: Compared to plant sources, animal-sourced foods do not provide so great an amount of vitamin C, and what there is, is largely destroyed by the heat used when it is cooked. For example, raw chicken liver contains 17.9 mg/100 g, but fried, the content is reduced to 2.7 mg/100 g. Smoked products, such as beef sticks, retain some vitamin C however.


title: Vitamin C

text: Vitamin C is present in human breast milk at 5.0 mg/100 g. One tested sample of infant formula contained 6.1 mg/100 g. Cow's milk contains only 1.0 mg/ 100 g, but the heat of pasteurization destroys it. Goat's milk contains 1.3mg/100 g, unless pasteurized.


title: Vitamin C

text: Vitamin C chemically decomposes under certain conditions, many of which may occur during the cooking of food. Vitamin C concentrations in various food substances decrease with time in proportion to the temperature at which they are stored. Cooking can reduce the vitamin C content of vegetables by around 60%, possibly due to increased enzymatic destruction. Longer cooking times may add to this effect.


title: Vitamin C

text: Another cause of vitaminC loss from food is leaching, which transfers vitaminC to the cooking water, which is decanted and not consumed. Broccoli may retain vitaminC during cooking or storage more than most vegetables.


title: Vitamin C

text: Vitamin C dietary supplements are available as tablets, capsules, drink mix packets, in multi-vitamin/mineral formulations, in antioxidant formulations, and as crystalline powder. Vitamin C is also added to some fruit juices and juice drinks. Tablet and capsule content ranges from 25 mg to 1500 mg per serving. The most commonly used supplement compounds are ascorbic acid, sodium ascorbate and calcium ascorbate. Vitamin C molecules can also be bound to the fatty acid palmitate, creating ascorbyl palmitate, or else incorporated into liposomes.


title: Vitamin C

text: In 2014, the Canadian Food Inspection Agency evaluated the effect of fortification of foods with ascorbate in the guidance document, "Foods to Which Vitamins, Mineral Nutrients and Amino Acids May or Must be Added". Voluntary and mandatory fortification was described for various classes of foods. Among foods classified for mandatory fortification with vitaminC were fruit-flavored drinks, mixes, and concentrates, foods for a low-energy diet, meal replacement products, and evaporated milk.


title: Vitamin C

text: Ascorbic acid and some of its salts and esters are common additives added to various foods, such as canned fruits, mostly to slow oxidation and enzymatic browning. It may be used as a flour treatment agent used in breadmaking. As food additives, they are assigned E numbers, with safety assessment and approval the responsibility of the European Food Safety Authority. The relevant E numbers are:


title: Vitamin C

text: The stereoisomers of Vitamin C have a similar effect in food despite their lack of efficacy in humans. They include erythorbic acid and its sodium salt (E315, E316).


title: Vitamin C

text: Vitamin C – specifically, in the form of "ascorbate" – performs numerous physiological functions in the human body by serving as an enzyme substrate or cofactor and an electron donor. These functions include the synthesis of collagen, carnitine, and neurotransmitters; the synthesis and catabolism of tyrosine; and the metabolism of microsomes. During biosynthesis, ascorbate acts as a reducing agent, donating electrons and preventing oxidation to keep iron and copper atoms in their reduced states.


title: Vitamin C

text: From the U.S. National Institutes of Health: [In humans] "Approximately 70%–90% of vitamin C is absorbed at moderate intakes of 30–180 mg/day. However, at doses above 1,000 mg/day, absorption falls to less than 50%." It is transported through the intestine via both glucose-sensitive and glucose-insensitive mechanisms, so the presence of large quantities of sugar in the intestine can slow absorption.


title: Vitamin C

text: Ascorbic acid is absorbed in the body by both active transport and simple diffusion. Sodium-Dependent Active Transport—Sodium-Ascorbate Co-Transporters (SVCTs) and Hexose transporters (GLUTs)—are the two transporter proteins required for active absorption. SVCT1 and SVCT2 import the reduced form of ascorbate across plasma membranes. GLUT1 and GLUT3 are glucose transporters, and transfer only the dehydroascorbic acid (DHA) form of vitamin C. Although dehydroascorbic acid is absorbed in higher rate than ascorbate, the amount of dehydroascorbic acid found in plasma and tissues under normal conditions is low, as cells rapidly reduce dehydroascorbic acid to ascorbate.


title: Vitamin C

text: SVCTs appear to be the predominant system for vitamin C transport in the body, the notable exception being red blood cells, which lose SVCT proteins during maturation. In both vitamin C synthesizers (example: rat) and non-synthesizers (example: human) cells with few exceptions maintain ascorbic acid concentrations much higher than the approximately 50 micromoles/liter (µmol/L) found in plasma. For example, the ascorbic acid content of pituitary and adrenal glands can exceed 2,000 µmol/L, and muscle is at 200-300 µmol/L. The known coenzymatic functions of ascorbic acid do not require such high concentrations, so there may be other, as yet unknown functions. A consequence of all this high concentration organ content is that plasma vitamin C is not a good indicator of whole-body status, and people may vary in the amount of time needed to show symptoms of deficiency when consuming a diet very low in vitamin C.


title: Vitamin C

text: Excretion can be as ascorbic acid, via urine. In humans, during times of low dietary intake, vitamin C is reabsorbed by the kidneys rather than excreted. Only when plasma concentrations are 1.4 mg/dL or higher does re-absorption decline and the excess amounts pass freely into the urine. This salvage process delays onset of deficiency. Ascorbic acid also converts (reversibly) to dehydroascorbate (DHA) and from that compound non-reversibly to 2,3-diketogulonate and then oxalate. These three compounds are also excreted via urine. Humans are better than guinea pigs at converting DHA back to ascorbate, and thus take much longer to become vitamin C deficient.


title: Vitamin C

text: The name "vitamin C" always refers to the -enantiomer of ascorbic acid and its oxidized forms, such as dehydroascorbate (DHA). Therefore, unless written otherwise, "ascorbate" and "ascorbic acid" refer in the nutritional literature to -ascorbate and -ascorbic acid respectively. Ascorbic acid is a weak sugar acid structurally related to glucose. In biological systems, ascorbic acid can be found only at low pH, but in solutions above pH 5 is predominantly found in the ionized form, ascorbate. All of these molecules have vitamin C activity and thus are used synonymously with vitamin C, unless otherwise specified.


title: Vitamin C

text: Numerous analytical methods have been developed for ascorbic acid detection. For example, vitamin C content of a food sample such as fruit juice can be calculated by measuring the volume of the sample required to decolorize a solution of dichlorophenolindophenol (DCPIP) and then calibrating the results by comparison with a known concentration of vitamin C.