Still basking in the afterglow of Monday's solar eclipse, Americans got to see another spectacular show — the two-hour documentary on NASA's twin Voyager probes titled "The Farthest: Voyager In Space" which aired on PBS, Wednesday night.

The documentary commemorates the 40th anniversary of the probes launched in 1977 in the months of August (Voyager 2) and September (Voyager 1) to study planets Jupiter and Saturn, taking advantage of a favorable alignment. The probes have sent tons of data back to earth about these two planets, with Voyager 2 even moving on to Uranus and Neptune. NASA's longest-living spacecraft are now assigned the task of exploring interstellar space.

The scientific achievements of the successful and ongoing mission were featured in the documentary along with interviews with many of the original and current mission team, including scientists and engineers, who spearheaded it and are still working on it, collecting data and sending commands to the spacecraft. Written and directed by documentary filmmaker Emer Reynolds, the documentary was screened at the Tribeca Film Festival and film festivals in Edinburgh, Seattle, Sydney and Dublin.  

Here are some facts on the nuclear-powered spacecraft:

  • Voyager 2 was launched on Aug. 20, 1977, from Cape Canaveral, Florida, aboard a Titan-Centaur rocket. Its twin was launched on Sept. 5, the same year, from the same location and on the same rocket.
  • Data sent back to earth by Voyager 1 showed that it had become the first man-made object to enter interstellar space and Voyager 2 is the only spacecraft to have flown by all four outer planets — Jupiter, Saturn, Uranus and Neptune.  The probes also explored 48 of those planets’ moons, systems of rings and magnetic fields, says NASA.
  • Long-lasting plutonium batteries for fuel were used when building the spacecraft and the batteries have lasted till today. While traveling, Voyager turns off everything except its essential functions, and because of this, it is thought that the batteries can last throughout the 2020s.
  • According to NASA, the two probes are now looking to find the heliopause boundary (boundary between the Sun's solar wind and interstellar medium), essentially the limits of the Sun’s magnetic field and of its solar wind. Once the craft achieve this, the two will be able to measure the interstellar fields, particles and waves without the solar wind playing a part.
  • Built at NASA’s Jet Propulsion Laboratory in California, both the aircraft contain messages to alien forms of lives if they encounter any. The message is recorded on phonograph record — a 12-inch gold-plated copper disk called the Golden Record, and contains images and sounds that show the diversity of life and culture on Earth. The contents were selected by a committee headed by Carl Sagan of Cornell University and they put together 115 images and an array of natural sounds to which they added select musical pieces from different cultures and eras, and spoken greetings from people of the earth in 55 languages.
  • Voyager 1 is at a distance of 20.8 billion kilometers from the sun as of August 2017 and Voyager 2 is at a distance of 17.2 billion kilometers.

Wednesday's documentary used period music that includes tracks by Pink Floyd, computer animations of the spacecraft in space and actual data from the missions.