Hi.
I saw this:
http://ift.tt/1fGKwoG
(see link for article)
Basically, it looks that according to the model these scientists came up with, planets with more than 1.5-2x Earth's mass will tend to accrete thick hydrogen atmospheres, akin to those of a gas giant: or more precisely, they will fail to lose those atmospheres. This applies to planets even with less mass than a full-blown gas giant.
They suggest a "sweet spot" of 0.5-1.5 Earth masses for an atmosphere more clement to life. It's interesting that Earth happens to be riiight in the middle of that range...
There appears to be empirical evidence in favor of this:
Looks like there are fewer potential homes for ET than we thought...
On the other hand, this really suggests the need for even better telescopes, to be able to get more detail on the "super-Earth" planets for which we don't have enough stuff to really understand their composition, and so get an empirically-based profile of what's out there.
I saw this:
http://ift.tt/1fGKwoG
Quote:
Super-Earths may be dead worlds Scientists find that planets that form from less massive cores can become benign habitats for life, whereas the larger objects instead end up as “mini-Neptunes” with thick atmospheres and probably stay sterile. |
(see link for article)
Basically, it looks that according to the model these scientists came up with, planets with more than 1.5-2x Earth's mass will tend to accrete thick hydrogen atmospheres, akin to those of a gas giant: or more precisely, they will fail to lose those atmospheres. This applies to planets even with less mass than a full-blown gas giant.
They suggest a "sweet spot" of 0.5-1.5 Earth masses for an atmosphere more clement to life. It's interesting that Earth happens to be riiight in the middle of that range...
There appears to be empirical evidence in favor of this:
Quote:
The ongoing discovery of low (average) density super-Earths supports the results of the study. Scientists will need to look even harder to find places where life could be found, setting a challenge for astronomers using the giant telescopes that will come into use in the next decade. |
Looks like there are fewer potential homes for ET than we thought...
On the other hand, this really suggests the need for even better telescopes, to be able to get more detail on the "super-Earth" planets for which we don't have enough stuff to really understand their composition, and so get an empirically-based profile of what's out there.
via JREF Forum http://ift.tt/1fGKwoI
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