Planets have to be about the size of Earth to be conducive for life.Byline: ANI
London, September 8 (ANI): In a new research, it has been determined that rocky worlds have to be about the size of Earth to be conducive for life.
According to according to
1. As stated or indicated by; on the authority of: according to historians.
2. In keeping with: according to instructions.
3. a report in New Scientist, the discovery of extrasolar ex·tra·so·lar
Being or originating outside the solar system an extrasolar planet. super-Earths - rocky planets about five to ten times the mass of Earth - has raised hopes that some may harbour life.
Life is comfortable on Earth in part because of its relatively stable climate and its magnetic field, which deflects cosmic radiation capable of damaging organic molecules as well as producing amazing auroras.
The long-term stability of Earth's climate depends on the way the planet's crust is broken up into plates, which continually slide over and under one another in a process called plate tectonics.
Carbon scrubbed from the atmosphere by natural chemical reactions gets buried and recycled within the Earth because of plate tectonics, part of a cycle that stabilises atmospheric carbon dioxide carbon dioxide, chemical compound, CO2, a colorless, odorless, tasteless gas that is about one and one-half times as dense as air under ordinary conditions of temperature and pressure. concentrations.
Now, it seems rocky worlds have to be about the size of Earth to have both plate tectonics and magnetic fields magnetic fields,
n.pl the spaces in which magnetic forces are detectable; created by magnetostrictive ultrasonic scalers to cause the tips of instruments such as ultrasonic scalers to vibrate. , according to Vlada Stamenkovic of the German Aerospace Center The German Aerospace Center (DLR) (German: Deutsches Zentrum für Luft- und Raumfahrt e.V.) is the national research center for aviation and space flight of the Federal Republic of Germany and the German Space Agency. DLR is a member in the Helmholtz Association. in Berlin.
Heat from Earth's core creates the convection currents needed for plate tectonics. Such currents generate the force to tear the crust, produce multiple plates and move those plates around.
Stamenkovic's team found that the pressure and viscosity inside a super-Earth would be so high that a stagnant, insulating layer would form outside the core, weakening the convective currents needed to drive plate tectonics thus making the process unlikely.
The researchers also found that the slow transfer of heat out of the core in super-Earths would prevent a sufficiently rapid circulation of their molten cores, robbing them of a magnetic field.
Planets about 0.5 to 2.5 times the mass of Earth are most likely to support plate tectonics. The limits are fuzzier for magnetic field generation, but also favour Earth-sized planets.
"Earth is special," said Stamenkovic.
But astrobiologist David Grinspoon of the Denver Museum of Nature and Science The Denver Museum Of Nature and Science (DMNS) is the main natural history museum in Denver, Colorado. Home to a number of exhibits, the museum focuses on research and education of the Denver Metro Area. in Colorado points out that Venus seems to have recycled its crust in volcanic outbursts despite a lack of plate tectonics.
While this has not stabilised Venus's climate, the possibility that other forms of crustal crust·al
Of or relating to a crust, especially that of the earth or the moon.
Adj. 1. crustal - of or relating to or characteristic of the crust of the earth or moon recycling on super-Earths might do so should not be ruled out. (ANI)
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