Extraterrestrial liquid water is water in its liquid state that naturally occurs outside Earth. It is a subject of wide interest because it is recognized as one of the key prerequisites for life as we know it and is thus surmised to be essential for extraterrestrial life.[1]
Although many celestial bodies in the Solar System have a hydrosphere, Earth is the only celestial body known to have stable bodies of liquid water on its surface, with oceanic water covering 71% of its surface,[2] which is essential to life on Earth. The presence of liquid water is maintained by Earth's atmospheric pressure and stable orbit in the Sun's circumstellar habitable zone, however, the origin of Earth's water remains uncertain.
The main methods currently used for confirmation are absorption spectroscopy and geochemistry. These techniques have proven effective for atmospheric water vapor and ice. However, using current methods of astronomical spectroscopy it is substantially more difficult to detect liquid water on terrestrial planets, especially in the case of subsurface water. Due to this, astronomers, astrobiologists and planetary scientists use habitable zone, gravitational and tidal theory, models of planetary differentiation and radiometry to determine the potential for liquid water. Water observed in volcanic activity can provide more compelling indirect evidence, as can fluvial features and the presence of antifreeze agents, such as salts or ammonia.
Using such methods, many scientists infer that liquid water once covered large areas of Mars and Venus.[3][4] Water is thought to exist as liquid beneath the surface of some planetary bodies, similar to groundwater on Earth. Water vapour is sometimes considered conclusive evidence for the presence of liquid water, although atmospheric water vapour may be found to exist in many places where liquid water does not. Similar indirect evidence, however, supports the existence of liquids below the surface of several moons and dwarf planets elsewhere in the Solar System.[1] Some are speculated to be large extraterrestrial "oceans".[1] Liquid water is thought to be common in other planetary systems, despite the lack of conclusive evidence, and there is a growing list of extrasolar candidates for liquid water. In June 2020, NASA scientists reported that it is likely that exoplanets with oceans may be common in the Milky Way galaxy, based on mathematical modeling studies.[5][6]
^ abcDyches, Preston; Chou, Felcia (7 April 2015). "The Solar System and Beyond is Awash in Water". NASA. Archived from the original on 10 April 2015. Retrieved 8 April 2015.
^"Earth". Nineplanets.org. 6 December 2019.
^"Mars Probably Once Had A Huge Ocean". Sciencedaily.com. 13 June 2007. Retrieved 22 January 2012.
^Owen, James (28 November 2007). "Venus Craft Reveals Lightning, Supports Watery Past". National Geographic News. Archived from the original on 30 November 2007. Retrieved 7 September 2016.
^NASA (18 June 2020). "Are planets with oceans common in the galaxy? It's likely, NASA scientists find". EurekAlert!. Retrieved 20 June 2020.
^Shekhtman, Lonnie; et al. (18 June 2020). "Are Planets with Oceans Common in the Galaxy? It's Likely, NASA Scientists Find". NASA. Retrieved 20 June 2020.
and 29 Related for: Extraterrestrial liquid water information
Extraterrestrialliquidwater is water in its liquid state that naturally occurs outside Earth. It is a subject of wide interest because it is recognized...
evidence supporting the presence of extraterrestrialliquidwater in the case of some planetary mass objects. Water vapor, which reacts to temperature...
Extraterrestrialliquidwater in the Solar System is likely uncommon, although it has been hypothesized to exist in some of its moons, and to have formerly...
Communication with extraterrestrial intelligence Arecibo message Astrolinguistics Wow! signal Circumstellar habitable zone Extraterrestrialliquidwater Planetary...
45°. In liquid form, H2O is also called "Water" at standard temperature and pressure. Because Earth's environment is relatively close to water's triple...
formula CH3CH2CHO. It is the 3-carbon aldehyde. It is a colourless, flammable liquid with a pungent and fruity odour. It is produced on a large scale industrially...
a more convenient, liquid fuel, is challenging because the reaction typically progresses all the way to carbon dioxide and water even with an insufficient...
the liquid can often be handled in the laboratory without external cooling. Household ammonia or ammonium hydroxide is a solution of NH3 in water. Pliny...
carbon dioxide, and is a supercritical fluid at the surface. Extraterrestrialliquidwater Lava planet List of largest lakes and seas in the Solar System...
astronomy) Extraterrestrial life, alien life, or colloquially simply aliens is life which does not originate from Earth. No extraterrestrial life has yet...
Callisto) also extends the range of possible environments. Extraterrestrialliquidwater Hypothetical types of biochemistry Robert A. Freitas Jr., Xenology:...
contact Earth. No transmissions and no firm evidence of intelligent extraterrestrial life have been detected or observed. This runs counter to the knowledge...
colorless, highly volatile and flammable liquid with a characteristic pungent odor. Acetone is miscible with water and serves as an important organic solvent...
Svishchev, I. M.; Kusalik, P. G. (January 1994). "Dynamics in liquidwater, water-d2, and water-t2: a comparative simulation study". The Journal of Physical...
their details: a habitable world is formed with a supply of minerals and liquidwater. Prebiotic synthesis creates a range of simple organic compounds, which...
ethylene oxide to methylethanolamines. Liquid methylamine has solvent properties analogous to those of liquid ammonia. Representative commercially significant...
Extraterrestrial material refers to natural objects now on Earth that originated in outer space. Such materials include cosmic dust and meteorites, as...
for human settlements on Mars Evolution of water on Mars and Earth Extraterrestrialliquidwater – Liquidwater naturally occurring outside Earth Lakes on...
in water as oxygen and is 2.5 times more soluble in water than nitrogen. Argon is colorless, odorless, nonflammable and nontoxic as a solid, liquid or...
(77 °F) and is a mobile liquid at 0 °C (32 °F) – viscosity of liquid ethylene oxide at 0 °C is about 5.5 times lower than that of water. The gas has a characteristic...
Washington. "Newly discovered form of salty ice could exist on surface of extraterrestrial moons". Phys.org. Lincoln, S. F.; Richens, D. T. and Sykes, A. G. (2003)...
Water (H2O) is a polar inorganic compound that is at room temperature a tasteless and odorless liquid, which is nearly colorless apart from an inherent...
Chan, Queenie H. S.; et al. (10 January 2018). "Organic matter in extraterrestrialwater-bearing salt crystals". Science Advances. 4 (1, eaao3521): eaao3521...
Cosmic dust – also called extraterrestrial dust, space dust, or star dust – is dust that occurs in outer space or has fallen onto Earth. Most cosmic dust...
alpha phase). Liquid nitrogen, a colourless fluid resembling water in appearance, but with 80.8% of the density (the density of liquid nitrogen at its...
ethanoate, is a carboxylate ester with the formula CH3COOCH3. It is a flammable liquid with a characteristically pleasant smell reminiscent of some glues and nail...
molecules. Formic acid forms a high-boiling azeotrope with water (107.3 °C; 77.5% formic acid). Liquid formic acid tends to supercool. Formic acid readily decomposes...
an ongoing scientific discussion, informed by what is known about extraterrestrial environments and about the chemical behaviour of various elements and...
calculating the Avogadro constant using three different methods, all involving liquid phase systems. First, he used a gamboge soap-like emulsion, second by doing...