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While the future can never be predicted with absolute certainty, present understanding in various scientific fields allows for the prediction of some far-future events, if only in the broadest outline. 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 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 rise over time. Stars will eventually exhaust their supply of hydrogen fuel and burn out. Close encounters between astronomical objects gravitationally fling planets from their star systems, and star systems from galaxies.

Physicists expect that matter itself will eventually come under the influence of radioactive decay, as even the most stable materials break apart into subatomic particles. Current data suggest that the universe has a flat geometry (or very close to flat), and thus will not collapse in on itself after a finite time, and the infinite future allows for the occurrence of a number of massively improbable events, such as the formation of Boltzmann brains.

The timelines displayed here cover events from the beginning of the 11th millennium to the furthest reaches of future time. A number of alternative future events are listed to account for questions still unresolved, such as whether humans will become extinct, whether protons decay, and whether the Earth survives when the Sun expands to become a red giant.

The Sweden Solar System is the world's largest permanent scale model of the Solar System. The Sun is represented by the Ericsson Globe in Stockholm, the largest hemispherical building in the world. The inner planets can also be found in Stockholm but the outer planets are situated northward in other cities along the Baltic Sea. The system was started by Nils Brenning and Gösta Gahm and is on the scale of 1:20 million.

The Wanggongchang Explosion (Chinese: 王恭廠大爆炸), also known as the Great Tianqi Explosion (天啟大爆炸), Wanggongchang Calamity (王恭廠之變) or Beijing Explosive Incident in Late Ming (晚明北京爆炸事件), was an unexplained catastrophic explosion that occurred on May 30 of the Chinese calendar in 1626 AD during the late reign of Tianqi Emperor, at the heavily populated Ming China capital Beijing, and had reportedly killed around 20,000 people. The nature of the explosion is still unclear to this day, as it is estimated to have released energy equivalent to about 10-20 kiloton of TNT, similar to that of the Hiroshima bombing.

Saturn's hexagon is a persistent approximately hexagonal cloud pattern around the north pole of the planet Saturn, located at about 78°N. The sides of the hexagon are about 14,500 km (9,000 mi) long, which is about 2,000 km (1,200 mi) longer than the diameter of Earth. The hexagon may be a bit more than 29,000 km (18,000 mi) wide, may be 300 km (190 mi) high, and may be a jet stream made of atmospheric gases moving at 320 km/h (200 mph). It rotates with a period of 10h 39m 24s, the same period as Saturn's radio emissions from its interior. The hexagon does not shift in longitude like other clouds in the visible atmosphere.

Saturn's hexagon was discovered during the Voyager mission in 1981, and was later revisited by Cassini-Huygens in 2006. During the Cassini mission, the hexagon changed from a mostly blue color to more of a golden color. Saturn's south pole does not have a hexagon, as verified by Hubble observations. It does, however, have a vortex, and there is also a vortex inside the northern hexagon. Multiple hypotheses for the hexagonal cloud pattern have been developed.

319 Leona (provisional designation A920 HE), is a dark asteroid and tumbling slow rotator from the outermost regions of the asteroid belt, approximately 70 kilometers in diameter. It was discovered on 8 October 1891, by French astronomer Auguste Charlois at Nice Observatory in southwestern France. Any reference of its name to a person is unknown. On 12 December 2023 Leona will occult Betelgeuse as seen from southern Europe.

Robert Burnham Jr. (June 16, 1931 – March 20, 1993) was an American astronomer, best known for writing the classic three-volume Burnham's Celestial Handbook. He is the discoverer of numerous asteroids including the Mars crossing asteroid 3397 Leyla, as well as six comets.

Burnham's late years were tragic; he died destitute and alone. However, he is remembered by a generation of deep sky observers for his unique contribution to astronomy, the Celestial Handbook. The main-belt asteroid 3467 Bernheim was named in his honor.

On April 11, 2019, the Israeli spacecraft Beresheet crashed into the Moon during a failed landing attempt. Its payload included a few thousand tardigrades. Initial reports suggested they could have survived the crash landing. If any of them did survive, they would be the second animal species to reach the Moon, after humans.

We believe the chances of survival for the tardigrades... are extremely high.

Superionic water, also called superionic ice or ice XVIII, is a phase of water that exists at extremely high temperatures and pressures. In superionic water, water molecules break apart and the oxygen ions crystallize into an evenly spaced lattice while the hydrogen ions float around freely within the oxygen lattice. The freely mobile hydrogen ions make superionic water almost as conductive as typical metals, making it a superionic conductor. It is one of the 19 known crystalline phases of ice. Superionic water is distinct from ionic water, which is a hypothetical liquid state characterized by a disordered soup of hydrogen and oxygen ions.

While theorized for decades, it was not until the 1990s that the first experimental evidence emerged for superionic water. Initial evidence came from optical measurements of laser-heated water in a diamond anvil cell, and from optical measurements of water shocked by extremely powerful lasers. The first definitive evidence for the crystal structure of the oxygen lattice in superionic water came from x-ray measurements on laser-shocked water which were reported in 2019.

If it were present on the surface of the Earth, superionic ice would rapidly decompress. In May 2019, scientists at the Lawrence Livermore National Laboratory (LLNL) were able to synthesize superionic ice, confirming it to be almost four times as dense as normal ice and black in color.

Superionic water is theorized to be present in the mantles of giant planets such as Uranus and Neptune.

Vulcan was a theorized planet that some pre-20th century astronomers thought existed in an orbit between Mercury and the Sun. Speculation about, and even purported observations of, intermercurial bodies or planets date back to the beginning of the 17th century. The case for their probable existence was bolstered by the support of the French mathematician Urbain Le Verrier, who had predicted the existence of Neptune using disturbances in the orbit of Uranus. By 1859 he had confirmed unexplained peculiarities in Mercury's orbit and predicted that they had to be the result of the gravitational influence of another unknown nearby planet or series of asteroids. A French amateur astronomer's report that he had observed an object passing in front of the Sun that same year led Le Verrier to announce that the long sought after planet, which he gave the name Vulcan, had been discovered at last.

Many searches were conducted for Vulcan over the following decades, but despite several claimed observations, its existence could not be confirmed. The need for the planet as an explanation for Mercury's orbital peculiarities was later rendered unnecessary when Einstein's 1915 theory of general relativity showed that Mercury's departure from an orbit predicted by Newtonian physics was explained by effects arising from the curvature of spacetime caused by the Sun's mass.