Timeline of the far future

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This article is about the far future as postulated by science. For the far future in fiction, see Far future in science fiction and popular culture. For the far future in religion, see Far future in religion. For other uses, see Timeline of the future.
An artist's concept of a charred Earth seven billion years from now, after the Sun has entered the red giant phase

While scientific predictions of the future can never be absolutely certain,[1] present understanding in various fields allows for the prediction of far future events, if only in the broadest strokes. These fields include astrophysics, which has revealed how planets and stars form, interact, and die; particle physics, which has revealed how matter behaves at the smallest scales; evolutionary biology, which predicts how life will evolve over time; and plate tectonics, which shows how continents shift over millennia.

All projections of the future of the Earth, the Solar System, and the Universe must account for the second law of thermodynamics, which states that entropy, or a loss of the energy available to do work, must increase over time.[2] Stars eventually must exhaust their supply of hydrogen fuel and burn out. Close encounters gravitationally fling planets from their star systems, and star systems from galaxies.[3]


The timelines displayed here cover events from roughly eight thousand years from now[a] to the furthest reaches of future time. A number of alternate future events are listed to account for questions still unresolved, such as whether humans will become extinct, whether protons decay, or whether Earth will survive the Sun's expansion into a red giant.


Astronomy and astrophysics Astronomy and astrophysics
Geology and planetary science Geology and planetary science
Biology Biology
Particle physics Particle physics
Mathematics Mathematics
Technology and culture Technology and culture

Future of the Earth, the Solar System and the Universe[edit]

Key.svg Years from now Event
Astronomy and astrophysics 10,000[b] The red supergiant star Antares will likely have exploded in a supernova. The explosion is expected to be easily visible in daylight.[8]
Geology and planetary science 25,000 The northern Martian polar ice cap could recede as Mars reaches a warming peak of the northern hemisphere during the ~50,000 year perihelion precession aspect of its Milankovitch cycle.[9][10]
Astronomy and astrophysics 36,000 The small red dwarf Ross 248 will pass within 3.024 light years of Earth, becoming the closest star to the Sun.[11] It will recede after about 8,000 years, making first Alpha Centauri again and then Gliese 445 the nearest stars[11] (see timeline).
Geology and planetary science 50,000 According to Berger and Loutre, the current interglacial period ends[12] sending the Earth back into a glacial period of the current ice age, regardless of the effects of anthropogenic global warming.

Niagara Falls will have eroded away the remaining 32 km to Lake Erie, and ceased to exist.[13]


Astronomy and astrophysics 50,000 The length of the day used for astronomical timekeeping reaches about 86,401 SI seconds, due to lunar tides decelerating the Earth's rotation. Under the present-day timekeeping system, a leap second will need to be added to the clock every day.[15]
Astronomy and astrophysics 100,000[b] The hypergiant star VY Canis Majoris will likely have exploded in a hypernova.[17]
Geology and planetary science 100,000[b] Earth will likely have undergone a supervolcanic eruption large enough to erupt 400 km3 of magma. For comparison, Lake Erie is 484 km3 .[18]
Biology 100,000 Native North American earthworms, such as Megascolecidae, will have naturally spread north through the United States Upper Midwest to the Canada–US border, recovering from the Laurentide ice sheet glaciation (38°N to 49°N), assuming a migration rate of 10 m / year.[19] (However, non-native invasive earthworms of North America have already been introduced by humans on a much shorter timescale, causing a shock to the regional ecosystem).
Astronomy and astrophysics ~300,000[b] At some point in the next "several" hundred thousand years, the Wolf-Rayet star WR 104 is expected to explode in a supernova. It has been suggested that it may produce a gamma ray burst that could pose a threat to life on Earth should its poles be aligned 12° or lower towards Earth. The star's axis of rotation has yet to be determined with certainty.[22]
Astronomy and astrophysics 500,000[b] Earth will likely have been hit by an asteroid of roughly 1 km in diameter, assuming it cannot be averted.[23]
Geology and planetary science 950,000 Meteor Crater, a large impact crater in Arizona considered the "freshest" of its kind, will have been eroded away by this time.[25]
Geology and planetary science 1 million[b] Earth will likely have undergone a supervolcanic eruption large enough to erupt 3,200 km3 of magma, an event comparable to the Toba supereruption 75,000 years ago.[18]
Astronomy and astrophysics 1 million[b] Highest estimated time until the red supergiant star Betelgeuse explodes in a supernova. The explosion is expected to be easily visible in daylight.[26][27]
Astronomy and astrophysics 1.4 million The star Gliese 710 will pass as close as 1.1 light years to the Sun before moving away. This may gravitationally perturb members of the Oort cloud, a halo of icy bodies orbiting at the edge of the Solar System, thereafter increasing the likelihood of a cometary impact in the inner Solar System.[28]
Biology 2 million Estimated time required for coral reef ecosystems to physically rebuild and biologically recover from current human-caused ocean acidification.[29]
Astronomy and astrophysics 2.7 million Average orbital half-life of current centaurs, that are unstable because of gravitational interaction of the several outer planets.[31] See predictions for notable centaurs.
Geology and planetary science 10 million The widening East African Rift valley is flooded by the Red Sea, causing a new ocean basin to divide the continent of Africa[32] and the African Plate into the newly formed Nubian Plate and the Somali Plate.

Even without a mass extinction, by this time most current species will have disappeared through the background extinction rate, with many clades gradually evolving into new forms.[34] (However, without a mass extinction, there will now be an ecological crisis requiring millions of years of recovery).

Astronomy and astrophysics 50 million Maximum estimated time before the moon Phobos collides with Mars.[35]
Geology and planetary science 50 million The Californian coast begins to be subducted into the Aleutian Trench due to its northward movement along the San Andreas Fault.[36]

Africa's collision with Eurasia closes the Mediterranean Basin and creates a mountain range similar to the Himalayas.[37]

The Appalachian Mountains peaks will largely erode away,[38] weathering at 5.7 Bubnoff units, although topography will actually increase as regional valleys deepen at twice this rate.[39]

Geology and planetary science 50 - 60 million The Canadian Rockies will erode away to a plain, assuming a rate of 60 Bubnoff units.[40] (The Southern Rockies in the United States are eroding at a somewhat slower rate.[41])
Geology and planetary science 50 - 400 million Estimated time for Earth to naturally replenish its fossil fuel reserves.[42]
Geology and planetary science 80 million The Big Island becomes the last of the current Hawaiian Islands to sink beneath the surface of the ocean.[43]
Astronomy and astrophysics 100 million[b] Earth will likely have been hit by an asteroid comparable in size to the one that triggered the K–Pg extinction 65 million years ago, assuming it cannot be averted.[44]
Geology and planetary science 400–500 million The supercontinent (Pangaea Ultima, Novopangaea, or Amasia) will likely have rifted apart.[49]
Astronomy and astrophysics 500–600 million[b] Estimated time until a gamma ray burst, or massive, hyperenergetic supernova, occurs within 6,500 light-years of Earth; close enough for its rays to affect Earth's ozone layer and potentially trigger a mass extinction, assuming the hypothesis is correct that a previous such explosion triggered the Ordovician–Silurian extinction event. However, the supernova would have to be precisely oriented relative to Earth to have any negative effect.[50]
Geology and planetary science 600 million The Sun's increasing luminosity begins to disrupt the carbonate–silicate cycle; higher luminosity increases weathering of surface rocks, which traps carbon dioxide in the ground as carbonate. As water evaporates from the Earth's surface, rocks harden, causing plate tectonics to slow and eventually stop. Without volcanoes to recycle carbon into the Earth's atmosphere, carbon dioxide levels begin to fall.[52] By this time, carbon dioxide levels will fall to the point at which C3 photosynthesis is no longer possible. All plants that utilize C3 photosynthesis (~99 percent of present-day species) will die.[53]
Geology and planetary science 800 million Carbon dioxide levels fall to the point at which C4 photosynthesis is no longer possible.[53] Free oxygen and ozone disappear from the atmosphere. Multicellular life dies out.[54]
Geology and planetary science 1 billion[c] The Sun's luminosity has increased by 10 percent, causing Earth's surface temperatures to reach an average of ~320 K (47 °C, 116 °F). The atmosphere will become a "moist greenhouse", resulting in a runaway evaporation of the oceans.[55] Pockets of water may still be present at the poles, allowing abodes for simple life.[56][57]
Geology and planetary science 1.3 billion Eukaryotic life dies out due to carbon dioxide starvation. Only prokaryotes remain.[54]
Astronomy and astrophysics 1.5–1.6 billion The Sun's increasing luminosity causes its circumstellar habitable zone to move outwards; as carbon dioxide increases in Mars's atmosphere, its surface temperature rises to levels akin to Earth during the ice age.[54][58]
Geology and planetary science 2.3 billion The Earth's outer core freezes, if the inner core continues to grow at its current rate of 1 mm per year.[59][60] Without its liquid outer core, the Earth's magnetic field shuts down,[61] and charged particles emanating from the Sun gradually deplete the atmosphere.[62]
Geology and planetary science 2.8 billion Earth's surface temperature, even at the poles, reaches an average of ~422 K (149 °C; 300 °F). At this point, life, now reduced to unicellular colonies in isolated, scattered microenvironments such as high-altitude lakes or subsurface caves, will completely die out.[52][63][d]
Astronomy and astrophysics 3 billion Median point at which the Moon's increasing distance from the Earth lessens its stabilising effect on the Earth's axial tilt. As a consequence, Earth's true polar wander becomes chaotic and extreme.[64]
Astronomy and astrophysics 3.3 billion One percent chance that Jupiter's gravity may make Mercury's orbit so eccentric as to collide with Venus, sending the inner Solar System into chaos and potentially leading to a planetary collision with Earth. Other possible scenarios include Mercury colliding with the Sun, being ejected from the Solar System, or colliding with Earth.[65]
Geology and planetary science 3.5–4.5 billion The amount of water vapour in the lower atmosphere increases to 40%. This, combined with the luminosity of the Sun reaching roughly 35–40% more than its present-day value, will result in Earth's atmosphere heating up and the surface temperature skyrocketing to roughly 1,600 K (1,330 °C; 2,420 °F), hot enough to melt surface rock.[66][67][68][69] This essentially will make the planet much like how Venus is today.[70]
Astronomy and astrophysics 4 billion Median point by which the Andromeda Galaxy will have collided with the Milky Way, which will thereafter merge to form a galaxy dubbed "Milkomeda".[72] The planets of the Solar System are expected to be relatively unaffected by this collision.[73][74][75]
Astronomy and astrophysics 5 billion With the hydrogen supply exhausted at its core, the Sun leaves the main sequence and begins to evolve into a red giant.[76]
Astronomy and astrophysics 7.5 billion Earth and Mars may become tidally locked with the expanding subgiant Sun.[58]
Astronomy and astrophysics 7.59 billion The Earth and Moon are very likely destroyed by falling into the Sun, just before the Sun reaches the tip of its red giant phase and its maximum radius of 256 times the present day value.[76][e] Before the final collision, the Moon possibly spirals below Earth's Roche limit, breaking into a ring of debris, most of which falls to the Earth's surface.[77]
Astronomy and astrophysics 7.9 billion The Sun reaches the tip of the red-giant branch of the Hertzsprung–Russell diagram, achieving its maximum radius of 256 times the present day value.[78] In the process, Mercury, Venus, very likely Earth, and possibly Mars are destroyed.[76]


Astronomy and astrophysics 8 billion The Sun becomes a carbon-oxygen white dwarf with about 54.05 percent its present mass.[76][80][81][f] At this point, if somehow the Earth survives, temperatures on the surface of the planet, as well as other remaining planets in the Solar System, will begin to start dropping rapidly, due to the white dwarf Sun emitting much less energy than it does today.
Astronomy and astrophysics 22 billion The end of the Universe in the Big Rip scenario, assuming a model of dark energy with w = −1.5.[82] Observations of galaxy cluster speeds by the Chandra X-ray Observatory suggest that the true value of w is ~-0.991, meaning the Big Rip will not occur.[83]
Astronomy and astrophysics 50 billion If the Earth and Moon are not engulfed by the Sun, by this time they will become tidelocked, with each showing only one face to the other.[84][85] Thereafter, the tidal action of the Sun will extract angular momentum from the system, causing the lunar orbit to decay and the Earth's spin to accelerate.[86]
Astronomy and astrophysics 100 billion The Universe's expansion causes all galaxies beyond the former Milky Way's Local Group to disappear beyond the cosmic light horizon, removing them from the observable universe.[87]
Astronomy and astrophysics 150 billion The cosmic microwave background cools from its current temperature of ~2.7 K to 0.3 K, rendering it essentially undetectable with current technology.[88]
Astronomy and astrophysics 450 billion Median point by which the ~47 galaxies[89] of the Local Group will coalesce into a single large galaxy.[4]


Astronomy and astrophysics 1.2x1013 (12 trillion) Estimated time until the red dwarf VB 10, as of 2016 the least massive main sequence star with an estimated mass of 0.075 M, runs out of hydrogen in its core and becomes a white dwarf.[92][93]



By this point, the Sun will have cooled to five degrees above absolute zero.[95]

Astronomy and astrophysics 1020 (100 quintillion) Estimated time until the Earth collides with the black dwarf Sun due to the decay of its orbit via emission of gravitational radiation,[97] if the Earth is not ejected from its orbit by a stellar encounter or engulfed by the Sun during its red giant phase.[97]
Particle physics 2×1036 The estimated time for all nucleons in the observable universe to decay, if the proton half-life takes its smallest possible value (8.2×1033 years).[98][99][g]
Particle physics 3×1043 Estimated time for all nucleons in the observable universe to decay, if the proton half-life takes the largest possible value, 1041 years,[4] assuming that the Big Bang was inflationary and that the same process that made baryons predominate over anti-baryons in the early Universe makes protons decay.[99][g] By this time, if protons do decay, the Black Hole Era, in which black holes are the only remaining celestial objects, begins.[3][4]
Particle physics 1065 Assuming that protons do not decay, estimated time for rigid objects like rocks to rearrange their atoms and molecules via quantum tunneling. On this timescale, all matter is liquid.[97]
Particle physics 1.342×1099 Estimated time until the central black hole of S5 0014+81, as of 2015 the most massive known with the mass of 40 billion solar masses, dissipates by the emission of Hawking radiation,[100] assuming zero angular momentum (non-rotating black hole). However, the black hole is on the state of accretion, so the time it takes may be longer than stated on the left.
Particle physics 10200 Estimated high time for all nucleons in the observable universe to decay, if they don't via the above process, through any one of many different mechanisms allowed in modern particle physics (higher-order baryon non-conservation processes, virtual black holes, sphalerons, etc.) on time scales of 1046 to 10200 years.[3]
Particle physics 101500 Assuming protons do not decay, the estimated time until all baryonic matter has either fused together to form iron-56 or decayed from a higher mass element into iron-56.[97] (see iron star)
Particle physics [h][i] Low estimate for the time until all objects exceeding the Planck mass collapse via quantum tunnelling into black holes, assuming no proton decay or virtual black holes.[97] On this vast timescale, even ultra-stable iron stars are destroyed by quantum tunnelling events. First iron stars of sufficient mass will collapse via tunnelling into neutron stars. Subsequently neutron stars and any remaining iron stars collapse via tunnelling into black holes. The subsequent evaporation of each resulting black hole into sub-atomic particles (a process lasting roughly 10100 years) is on these timescales instantaneous.
Particle physics [b] Estimated time for a Boltzmann brain to appear in the vacuum via a spontaneous entropy decrease.[6]
Particle physics High estimate for the time until all matter collapses into neutron stars or black holes, assuming no proton decay or virtual black holes,[97] which then (on these timescales) instantaneously evaporate into sub-atomic particles.
Particle physics High estimate for the time for the Universe to reach its final energy state, even in the presence of a false vacuum.[6]
Particle physics [b] Estimated time for random quantum fluctuations and quantum tunnelling to generate a new Big Bang.[101]

Because the total number of ways in which all the subatomic particles in the observable universe can be combined is ,[102][103] a number which, when multiplied by , disappears into the rounding error, this is also the time required for a quantum-tunnelled and quantum fluctuation-generated Big Bang to produce a new universe identical to our own, assuming that every new universe contained at least the same number of subatomic particles and obeyed laws of physics within the range predicted by string theory.[104]

More simply, by this time the entire life cycle of the universe, from Big Bang to final energy state to rebirth, will have repeated the same number of times as all possible combinations of subatomic particles in the observable universe.

Future of humanity[edit]

Key.svg Years from now Event
Biology 10,000 If globalization trends lead to panmixia, human genetic variation will no longer be regionalized, as the effective population size will equal the actual population size.[106] (This does not mean homogeneity, as minority traits will still be preserved, e.g., no disappearing blonde gene, but will rather be evenly distributed worldwide.)
Biology 2 million Vertebrate species separated for this long will generally undergo allopatric speciation.[111] Evolutionary biologist James W. Valentine predicted that if humanity has been dispersed among genetically isolated space colonies over this time, the galaxy will host an evolutionary radiation of multiple human species with a "diversity of form and adaptation that would astound us".[112] (This would be a natural process of isolated populations, unrelated to potential deliberate genetic enhancement technologies.)
technology and culture 5 – 50 million Shortest time by which the entire galaxy could be colonised by means within reach of current technology.[114]
Astronomy and astrophysics 1 billion Estimated time for an astroengineering project to alter the Earth's orbit, compensating for the Sun's increasing brightness and outward migration of the habitable zone, accomplished by repeated asteroid gravity assists.[116][117]

Spacecraft and space exploration[edit]


Key.svg Years from now Event
Astronomy and astrophysics 10,000 Pioneer 10 passes within 3.8 light years of Barnard's Star.[119]
Astronomy and astrophysics 25,000 The Arecibo message, a collection of radio data transmitted on 16 November 1974, reaches the distance of its destination, the globular cluster Messier 13.[120] This is the only interstellar radio message sent to such a distant region of the galaxy. There will be a 24-light-year shift in the cluster's position in the galaxy during the time it takes the message to reach it, but as the cluster is 168 light-years in diameter, the message will still reach its destination.[121] Any reply will take at least another 25,000 years.
Astronomy and astrophysics 32,000 Pioneer 10 passes within 3 light years of Ross 248.[122][123]
Astronomy and astrophysics 40,000 Voyager 1 passes within 1.6 light years of AC+79 3888, a star in the constellation Camelopardalis also known as Gliese 445.[124]
Astronomy and astrophysics 296,000 Voyager 2 passes within 4.3 light years of Sirius, the brightest star in the night sky.[124]
Astronomy and astrophysics 2 million Pioneer 10 passes near the bright star Aldebaran.[127]
Astronomy and astrophysics 4 million Pioneer 11 passes near one of the stars in the constellation Aquila.[127]

Technological projects[edit]

Key.svg Years from now Event



Human constructs[edit]

Key.svg Years from now Event
Geology and planetary science 50,000 Estimated atmospheric lifetime of tetrafluoromethane, the most durable greenhouse gas.[136]
Geology and planetary science 1 million Current glass objects in the environment will be decomposed.[137]


Without maintenance, the Great Pyramid of Giza will erode into unrecognizability.[139]

On the Moon, Neil Armstrong's "one small step" footprint at Tranquility Base will erode by this time, along with those left by all twelve Apollo moonwalkers, due to the accumulated effects of space weathering.[140][141] (Normal erosion processes active on Earth are not present due to the Moon's almost complete lack of atmosphere).

Geology and planetary science 7.2 million Without maintenance, Mount Rushmore will erode into unrecognizability.[142]

Astronomical events[edit]

Extremely rare astronomical events beginning at the 11th millennium AD (Year 10,001).

Date / Years from now Event
Astronomy and astrophysics 20 August, AD 10,663 A simultaneous total solar eclipse and transit of Mercury.[144]
Astronomy and astrophysics 28 February, AD 11,575 A simultaneous annular solar eclipse and transit of Mercury.[144]
Astronomy and astrophysics 17 September, AD 13,425 A near-simultaneous transit of Venus and Mercury.[144]
Astronomy and astrophysics AD 13,727 The Earth's axial precession will have made Vega the northern pole star.[145][146][147][148]
Astronomy and astrophysics 13,000 years By this point, halfway through the precessional cycle, Earth's axial tilt will be reversed, causing summer and winter to occur on opposite sides of Earth's orbit. This means that the seasons in the northern hemisphere, which experiences more pronounced seasonal variation due to a higher percentage of land, will be even more extreme, as it will be facing towards the Sun at Earth's perihelion and away from the Sun at aphelion.[146]
Astronomy and astrophysics 5 April, AD 15,232 A simultaneous total solar eclipse and transit of Venus.[144]
Astronomy and astrophysics 14,000-17,000 years The Earth's axial precession will make Canopus the South Star, but it will only be within 10° of the south celestial pole.[149]
Astronomy and astrophysics AD 20,346 Thuban will be the northern pole star.[150]
Astronomy and astrophysics AD 27,800 Polaris will again be the northern pole star.[151]
Astronomy and astrophysics 27,000 years The eccentricity of Earth's orbit will reach a minimum, 0.00236 (it is now 0.01671).[152][153]
Astronomy and astrophysics 26 July, AD 69,163 A simultaneous transit of Venus and Mercury.[144]
Astronomy and astrophysics AD 70,000 Comet Hyakutake returns to the inner solar system, after traveling in its orbit out to its aphelion 3410 A.U. from the Sun and back.[155]
Astronomy and astrophysics AD 571,741 A simultaneous transit of Venus and the Earth as seen from Mars[144]
Astronomy and astrophysics 6 million Comet C/1999 F1 (Catalina), one of the longest period comets known, returns to the inner solar system, after traveling in its orbit out to its aphelion 66,600 A.U. (1.05 light years) from the Sun and back.[156]

Calendric predictions[edit]

Key.svg Years from now Event
Astronomy and astrophysics 10,000
The Gregorian calendar will be roughly 10 days out of sync with the seasons.[157]
Astronomy and astrophysics 10,875 years, 258 days 10 June, AD 12,892 In the Hebrew calendar, due to a gradual drift with regard to the solar year, Passover will fall on the northern summer solstice (it is meant to fall around the spring equinox).[158]
Astronomy and astrophysics 18,857 years, 97 days AD 20,874 The lunar Islamic calendar and the solar Gregorian calendar will share the same year number. After this, the shorter Islamic calendar will slowly overtake the Gregorian.[159]
Astronomy and astrophysics 25,000
The Tabular Islamic calendar will be roughly 10 days out of sync with the Moon's phase.[160]
Astronomy and astrophysics 46,884 years, 156 days 1 March, AD 48,901[j] The Julian calendar (365.25 days) and Gregorian calendar (365.2425 days) will be one year apart.[161]

Nuclear power[edit]

Key.svg Years from now Event
Particle physics 10,000 The Waste Isolation Pilot Plant, for nuclear weapons waste, is planned to be protected until this time, with a "Permanent Marker" system designed to warn off visitors through both multiple languages (the six UN languages and Navajo) and through pictograms.[162] (The Human Interference Task Force has provided the theoretical basis for United States plans for future nuclear semiotics.)
Particle physics 20,000 The Chernobyl Exclusion Zone, the 2,600 km2 (1,000 sq mi) area of Ukraine and Belarus left deserted by the 1986 Chernobyl disaster, becomes safe for human life.[163]
Geology and planetary science 60,000 Estimated supply lifespan of fission-based light water reactor reserves if it is possible to extract all the uranium from seawater, assuming 2009 world energy consumption.[164]

Graphical timelines[edit]

For graphical, logarithmic timelines of these events see:

See also[edit]


  2. ^ a b c d e f g h i j k This represents the time by which the event will most probably have happened. It may occur randomly at any time from the present.
  3. ^ Units are short scale
  8. ^ is 1 followed by 1026 (100 septillion) zeroes.
  10. ^ Manually calculated from the fact that the calendars were 10 days apart in 1582 and grew further apart by 3 days every 400 years. 1 March AD 48900 (Julian) and 1 March AD 48901 (Gregorian) are both Tuesday. The Julian day number (a measure used by astronomers) at Greenwich mean midnight (start of day) is 19 581 842.5 for both dates.


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