The tidal forces of small stars would make the so-called non-existent "habitable zone" Goldilock or for any terrestrial planets. This is the main result of a recently published study by a team of astronomers led by René Heller Astrophysical Institute Potsdam (AIP) .
Since confirmation of the first extrasolar planet in 1995, one of the main goals of the scientists has been the search for habitable worlds like Earth, located in the habitable zone of the star belongs to.
As known, the "habitable zone" of a star is the portion of space around it in which a terrestrial planet like the Earth could easily hold the liquid water.
Water is retained by exobiology, the main molecule suitable to host life. So that water can exist liquid state, we need a suitable temperature and atmosphere able to hold the correct pressure.
Through the study of the tides caused by the low-mass stars on potential Earth-like planets hosted, Heller and his colleagues concluded that tidal effects would change the traditional concept of the habitable zone.
Heller concluded that three different effects. First, the tides may tilt the axis of rotation of a planet until it was perpendicular to its orbit in just a few million years.
In comparison, the Earth's axis of rotation of the Earth is tilted 23.5 degrees, an effect that causes the succession of four seasons and that fosters ideal climatic variation in the development of useful life and the water cycle.
Because of this lack of effect, there would be no seasonal variations on these planets similar to Earth, located in the habitable zone of low-mass stars. These planets would therefore be enormous differences in surface temperature with the perpetually frozen poles and the equator hot that would slowly evaporate the whole atmosphere. This temperature difference may cause strong winds and storms. The second effect of these currents would be to heat the extrasolar planet, very similar to the tidal heating of Io, a moon of Jupiter shows a global volcanism.
Finally, the tides could cause the synchronization of the planet's rotation period (the "day") with the orbital period (the 'years').
This configuration is identical to the Earth-Moon system. One side would be completely in the shadows while another would be eternally illuminated by the extreme radiation of the star.
habitable zone around low-mass star is therefore not very conducive to the development of life and may even be hostile to this process.
From the perspective of the observer, the low-mass stars have so far been the most promising candidates to search for habitable exoplanets.
Now, thanks to the results of Heller, the extrasolar planets similar to Land that have already been found in the habitable zone of conventional low-mass stars, should be reviewed to assess the effects of the tide.
Heller and his colleagues have applied their theory to GI581g: a recently discovered extrasolar planet candidate to host life.
GI581g really should not have the rotation of the seasons and your day should be synchronized with his year. Probably there would be water on the surface of the planet, making it uninhabitable.
Since confirmation of the first extrasolar planet in 1995, one of the main goals of the scientists has been the search for habitable worlds like Earth, located in the habitable zone of the star belongs to.
As known, the "habitable zone" of a star is the portion of space around it in which a terrestrial planet like the Earth could easily hold the liquid water.
Water is retained by exobiology, the main molecule suitable to host life. So that water can exist liquid state, we need a suitable temperature and atmosphere able to hold the correct pressure.
Through the study of the tides caused by the low-mass stars on potential Earth-like planets hosted, Heller and his colleagues concluded that tidal effects would change the traditional concept of the habitable zone.
Heller concluded that three different effects. First, the tides may tilt the axis of rotation of a planet until it was perpendicular to its orbit in just a few million years.
In comparison, the Earth's axis of rotation of the Earth is tilted 23.5 degrees, an effect that causes the succession of four seasons and that fosters ideal climatic variation in the development of useful life and the water cycle.
Because of this lack of effect, there would be no seasonal variations on these planets similar to Earth, located in the habitable zone of low-mass stars. These planets would therefore be enormous differences in surface temperature with the perpetually frozen poles and the equator hot that would slowly evaporate the whole atmosphere. This temperature difference may cause strong winds and storms. The second effect of these currents would be to heat the extrasolar planet, very similar to the tidal heating of Io, a moon of Jupiter shows a global volcanism.
Finally, the tides could cause the synchronization of the planet's rotation period (the "day") with the orbital period (the 'years').
This configuration is identical to the Earth-Moon system. One side would be completely in the shadows while another would be eternally illuminated by the extreme radiation of the star.
habitable zone around low-mass star is therefore not very conducive to the development of life and may even be hostile to this process.
From the perspective of the observer, the low-mass stars have so far been the most promising candidates to search for habitable exoplanets.
Now, thanks to the results of Heller, the extrasolar planets similar to Land that have already been found in the habitable zone of conventional low-mass stars, should be reviewed to assess the effects of the tide.
Heller and his colleagues have applied their theory to GI581g: a recently discovered extrasolar planet candidate to host life.
GI581g really should not have the rotation of the seasons and your day should be synchronized with his year. Probably there would be water on the surface of the planet, making it uninhabitable.
Heller then said "I think the possibility of life existing on extrasolar planets in the habitable zone around a traditional low-mass stars are quite low, if you consider the effects of tide. If you really want to find a second Earth, you probably need to first find a second sun. "
Translation by Arthur McPaul
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Translation by Arthur McPaul
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