Timeline of the far future
While predictions of the future can never be absolutely certain, present scientific understanding in various fields has allowed a projected course for the farthest future events to be sketched out, 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, and plate tectonics, which shows how continents shift over millennia.
All predictions 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. Stars must eventually exhaust their supply of hydrogen fuel and burn out; close encounters will gravitationally fling planets from their star systems, and star systems from galaxies. Eventually, matter itself will come under the influence of radioactive decay, as even the most stable materials break apart into subatomic particles. However, as current data suggest that the Universe is flat, and thus will not collapse in on itself after a finite time, the infinite future potentially allows for the occurrence of a number of massively improbable events, such as the formation of a Boltzmann brain.
These timelines cover events from roughly eight thousand years from now[a] to the farthest reaches of future time. A number of alternate future events are listed to account for questions still unresolved, such as whether humans survive, whether protons decay or whether the Earth will be destroyed by the Sun's expansion into a red giant.
|Event is determined via|
|Astronomy and astrophysics|
|Geology and planetary science|
|Technology and culture|
Future of the Earth, the Solar System and the Universe
|Years from now||Event|
|36,000||The small red dwarf star Ross 248 passes within 3.024 light years of Earth, becoming the closest star to the Sun. It will recede after about 8,000 years, making first Alpha Centauri and then Gliese 445 the nearest stars (see timeline).|
|50,000||The current interglacial period ends, according to the work of Berger and Loutre, sending the Earth back into a glacial period of the current ice age, assuming limited effects of anthropogenic global warming.|
|50,000||The length of the day used for astronomical timekeeping reaches about 86,401 SI seconds, due to lunar tides braking the Earth's rotation. Under the present-day timekeeping system, a leap second will need to be added to the clock every day.|
|100,000||The proper motion of stars across the celestial sphere, which is the result of their movement through the galaxy, renders many of the constellations unrecognisable.|
|100,000[b]||The hypergiant star VY Canis Majoris will have likely exploded in a hypernova.|
|100,000[b]||Earth will likely have undergone a supervolcanic eruption large enough to erupt 400 km3 of magma.|
|250,000||Lōʻihi, the youngest volcano in the Hawaiian–Emperor seamount chain, rises above the surface of the ocean and becomes a new volcanic island.|
|500,000[b]||Earth will have likely been hit by a meteorite of roughly 1 km in diameter, assuming it cannot be averted.|
|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.|
|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.|
|1.4 million||The star Gliese 710 passes 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.|
|8 million||The moon Phobos comes within 7,000 km of Mars, the Roche limit, at which point tidal forces will disintegrate the moon and turn it into a ring of orbiting debris that will continue to spiral in toward the planet.|
|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.|
|11 million||The ring of debris around Mars hits the surface of the planet.|
|50 million||The Californian coast begins to be subducted into the Aleutian Trench due to its northward movement along the San Andreas Fault.|
|100 million[b]||Earth will have likely been hit by a meteorite comparable in size to the one that triggered the K–Pg extinction 65 million years ago.|
|230 million||Beyond this time, the orbits of the planets become impossible to predict due to the limitations of Lyapunov time.|
|240 million||From its present position, the Solar System completes one full orbit of the Galactic center.|
|250 million||All the continents on Earth may fuse into a supercontinent. Three potential arrangements of this configuration have been dubbed Amasia, Novopangaea, and Pangaea Ultima.|
|400–500 million||The supercontinent (Pangaea Ultima, Novopangaea, or Amasia) will have likely rifted apart.|
|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.|
|600 million||Tidal acceleration moves the Moon far enough from Earth that total solar eclipses are no longer possible.|
|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. By this time, they 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.|
|800 million||Carbon dioxide levels fall to the point at which C4 photosynthesis is no longer possible. Multicellular life dies out.|
|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. Pockets of water may still be present at the poles, allowing abodes for simple life.|
|1.3 billion||Eukaryotic life dies out due to carbon dioxide starvation. Only prokaryotes remain.|
|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.|
|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. Without its liquid outer core, the Earth's magnetic field shuts down, and charged particles emanating from the Sun strip away the ozone layer, which protects the Earth from harmful ultraviolet rays.|
|2.8 billion||Earth's surface temperature, even at the poles, reaches an average of ~420 K (147 °C, 296 °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.[d]|
|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.|
|3.3 billion||1 percent chance that Mercury's orbit may become so elongated as to collide with Venus, sending the inner Solar System into chaos and potentially leading to a planetary collision with Earth.|
|3.5 billion||Surface conditions on Earth are comparable to those on Venus today.|
|3.6 billion||Neptune's moon Triton falls through the planet's Roche limit, potentially disintegrating into a planetary ring system similar to Saturn's.|
|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". The planets of the Solar System are expected to be relatively unaffected by this collision. |
|5.4 billion||With the hydrogen supply exhausted at its core, the Sun leaves the main sequence and begins to evolve into a red giant.|
|7.5 billion||Earth and Mars may become tidally locked with the expanding Sun.|
|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. In the process, Mercury, Venus and possibly Earth are destroyed.|
|8 billion||Sun becomes a carbon-oxygen white dwarf with about 54.05 percent its present mass.[e]|
|20 billion||The end of the Universe in the Big Rip scenario, assuming a model of dark energy with w = −1.5. Observations of galaxy cluster speeds by the Chandra X-ray Observatory suggest that this will not occur.|
|50 billion||Assuming both survive the Sun's expansion, by this time the Earth and the Moon become tidelocked, with each showing only one face to the other. 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.|
|100 billion||The Universe's expansion causes all galaxies beyond the Milky Way's Local Group to disappear beyond the cosmic light horizon, removing them from the observable universe.|
|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.|
|450 billion||Median point by which the ~47 galaxies of the Local Group will coalesce into a single large galaxy.|
|800 billion||Expected time when the net light emission from the combined Milkomeda galaxy begins to decline as the red dwarf stars pass through their blue dwarf stage of peak luminosity.|
|1012 (1 trillion)||Low estimate for the time until star formation ends in galaxies as galaxies are depleted of the gas clouds they need to form stars.
The universe's expansion, assuming a constant dark energy density, multiplies the wavelength of the cosmic microwave background by 1029, exceeding the scale of the cosmic light horizon and rendering its evidence of the Big Bang undetectable. However, it may still be possible to determine the expansion of the universe through the study of hypervelocity stars.
|3×1013 (30 trillion)||Estimated time for the remnant Sun to undergo a close encounter with another star in the local Solar neighborhood. Whenever two stars (or stellar remnants) pass close to each other, their planets' orbits can be disrupted, potentially ejecting them from the system entirely. On average, the closer a planet's orbit to its parent star, the longer it takes to be ejected in this manner, because stars rarely pass so closely.|
|1014 (100 trillion)||High estimate for the time until normal star formation ends in galaxies. This marks the transition from the Stelliferous Era to the Degenerate Era; with no free hydrogen to form new stars, all remaining stars slowly exhaust their fuel and die.|
|1.1–1.2×1014 (110–120 trillion)||Time by which all stars in the universe will have exhausted their fuel (the longest-lived stars, low-mass red dwarfs, have lifespans of roughly 10–20 trillion years). After this point, the stellar-mass objects remaining are stellar remnants (white dwarfs, neutron stars and black holes). Brown dwarfs also remain.
Collisions between brown dwarfs will create new red dwarf stars on a marginal level: on average, about 100 will be present in the galaxy. Collisions between stellar remnants will create occasional supernovae.
|1015 (1 quadrillion)||Estimated time until stellar close encounters detach all planets in Solar Systems from their orbits.|
|1019 to 1020 (10–100 quintillion)||Estimated time until 90% – 99% of brown dwarfs and stellar remnants are ejected from galaxies. When two objects pass close enough to each other, they exchange orbital energy, with lower-mass objects tending to gain energy. Through repeated encounters, the lower-mass objects can gain enough energy in this manner to be ejected from their galaxy. This process eventually causes the galaxy to eject the majority of its brown dwarfs and stellar remnants.|
|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, if the Earth is neither first engulfed by the red giant Sun a few billion years from now nor subsequently ejected from its orbit by a stellar encounter.|
|1030||Estimated time until those stars not ejected from galaxies (1% – 10%) fall into their galaxies' central supermassive black holes. By this point, with binary stars having fallen into each other, and planets into their stars, via emission of gravitational radiation, only solitary objects (stellar remnants, brown dwarfs, ejected planets, black holes) will remain in the universe.|
|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).[f]|
|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, 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.[f] By this time, if protons do decay, the Black Hole Era, in which black holes are the only remaining celestial objects, begins.|
|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.|
|5.8×1068||Estimated time until a stellar mass black hole with a mass of 3 solar masses decays by the Hawking process.|
|1.9×1098||Estimated time until NGC 4889, the currently largest known supermassive black hole with a mass of 21 billion solar masses, decays by the Hawking process.|
|1.7×10106||Estimated time until a supermassive black hole with a mass of 20 trillion solar masses decays by the Hawking process. This marks the end of the Black Hole Era. Beyond this time, if protons do decay, the Universe enters the Dark Era, in which all physical objects have decayed to subatomic particles, gradually winding down to their final energy state in the heat death of the universe.|
|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.|
|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. (see iron star)|
|[g][h]||Low estimate for the time until all matter collapses into black holes, assuming no proton decay. Subsequent Black Hole Era and transition to the Dark Era are, on this timescale, instantaneous.|
|Estimated time for a Boltzmann brain to appear in the vacuum via a spontaneous entropy decrease.|
|Estimated time for random quantum fluctuations to generate a new Big Bang, according to Carroll and Chen.|
|High estimate for the time until all matter collapses into black holes, again assuming no proton decay.|
|High estimate for the time for the Universe to reach its final energy state.|
This is a list of extremely rare astronomical events after the beginning of the 11th millennium AD (Year 10,001)
|Years from now||Date||Event|
||Earth's axial precession makes Deneb the North star.|
|8,649 years, 163 days||20 August, 10,663 AD||A simultaneous total solar eclipse and transit of Mercury.|
|8,705 years, 297 days||10,720 AD||The planets Mercury and Venus will both cross the ecliptic at the same time.|
|9,254 years, 168 days||25 August, 11,268 AD||A simultaneous total solar eclipse and transit of Mercury.|
|9,560 years, 355 days||28 February, 11,575 AD||A simultaneous annular solar eclipse and transit of Mercury.|
||The Gregorian calendar will be roughly 10 days out of sync with the Sun's position in the sky.|
|11,411 years, 191 days||17 September 13,425 AD||A near-simultaneous transit of Venus and Mercury.|
||The Earth's axial precession will make Vega the North Star.|
||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.|
||The Earth's axial precession will make Canopus the South Star, but it will only be within 10° of the south celestial pole.|
|13,218 years, 26 days||5 April, 15,232 AD||A simultaneous total solar eclipse and transit of Venus.|
|13,776 years, 41 days||20 April, 15,790 AD||A simultaneous annular solar eclipse and transit of Mercury.|
|18,859 years, 297 days||20,874 AD||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.|
||The eccentricity of Earth's orbit will reach a minimum, 0.00236 (it is now 0.01671).[i]|
|36,158 years, 205 days||October, 38,172 AD||A transit of Uranus from Neptune, the rarest of all planetary transits.[j]|
|46,886 years, 356 days||1 March, 48,901 AD||The Julian calendar (365.25 days) and Gregorian calendar (365.2425 days) will be one year apart.[k]|
|65,158 years, 297 days||67,173 AD||The planets Mercury and Venus will both cross the ecliptic at the same time.|
|67,149 years, 138 days||26 July, 69,163 AD||A simultaneous transit of Venus and Mercury.|
|222,494 years, 17 days||27 and 28 March, 224,508 AD||Respectively, Venus and then Mercury will transit the Sun.|
|569,726 years, 297 days||571,741 AD||A simultaneous transit of Venus and the Earth as seen from Mars|
Spacecraft and space exploration
To date five spacecraft (Voyagers 1 and 2, Pioneers 10 and 11 and New Horizons) are on trajectories which will take them out of the Solar System and into interstellar space. Barring an unlikely collision, the craft should persist indefinitely.
|Years from now||Event|
|10,000||Pioneer 10 passes within 3.8 light years of Barnard's Star.|
|25,000||The Arecibo message, a collection of radio data transmitted on 16 November 1974, reaches its destination, the globular cluster Messier 13. This is the only interstellar radio message sent to such a distant region of the galaxy. Assuming a similar mode of communication is employed, it should take at least as long again for any reply to reach Earth.|
|32,000||Pioneer 10 passes within 3 light years of Ross 248.|
|40,000||Voyager 1 passes within 1.6 light years of AC+79 3888, a star in the constellation Camelopardalis.|
|50,000||The KEO space time capsule, if it is launched, will reenter Earth's atmosphere.|
|296,000||Voyager 2 passes within 4.3 light years of Sirius, the brightest star in the night sky.|
|2 million||Pioneer 10 passes near the bright star Aldebaran.|
|4 million||Pioneer 11 passes near one of the stars in the constellation Aquila.|
|8 million||The LAGEOS satellites' orbits will decay, and they will re-enter Earth's atmosphere, carrying with them a message to any far future descendants of humanity, and a map of the continents as they are expected to appear then.|
Technology and culture
|Years from now||Event|
|10,000||Estimated lifespan of the Long Now Foundation's several ongoing projects, including a 10,000-year clock known as the Clock of the Long Now, the Rosetta Project, and the Long Bet Project.|
|10,000||Humanity is likely to be extinct by this date, according to one version of Brandon Carter's controversial Doomsday argument, which argues that half of the humans who will ever have lived have probably already been born.|
|100,000 – 1 million||Fastest time by which humanity could colonize the 100,000 light-year galaxy and become capable of harnessing all the energy of the galaxy, assuming a speed of 0.1c or greater.|
|5 – 50 million||Time by which the entire galaxy could be colonised by means within reach of current technology.|
For graphical, logarithmic timelines of these events see:
- Graphical timeline of the universe (to 8 billion years from now)
- Graphical timeline of the Stelliferous Era (to 1020 years from now)
- Graphical timeline from Big Bang to Heat Death (to 101000 years from now)
- Detailed logarithmic timeline
- Earth's location in the universe
- Space and survival
- Terasecond and longer
- Timeline of natural history
- Timeline of the Big Bang
- Timeline of the near future
- The precise cutoff point is 0:00 on Jan 1, 10,001 AD
- This represents the time by which the event will most probably have happened. It may occur randomly at any time from the present.
- Units are short scale
- There is a roughly 1 in 100,000 chance that the Earth might be ejected into interstellar space by a stellar encounter before this point, and a 1 in 3 million chance that it will then be captured by another star. Were this to happen, life, assuming it survived the interstellar journey, could potentially continue for far longer.
- Based upon the weighted least-squares best fit on p. 16 of Kalirai et al. with the initial mass equal to a solar mass.
- Around 264 half-lives. Tyson et al. employ the computation with a different value for half-life.
- is 1 followed by 1026 (100 septillion) zeroes.
- Although listed in years for convenience, the numbers beyond this point are so vast that their digits would remain unchanged regardless of which conventional units they were listed in, be they nanoseconds or star lifespans.
- Data for 0 to +10 Myr every 1000 years since J2000 from Astronomical solutions for Earth paleoclimates by Laskar, et al.
- Calculated using Aldo Vitagliano's Solex software. 2011-09-30.
- Manually calculated from the fact that the calendars were 10 days apart in 1582 and grew further apart by 3 days every 400 years.
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