http://jhuapl.edu/newscenter/pressreleases/2017/171019.asp
Narrow dense rings of comets are coming together to form planets on the outskirts of at least three distant solar systems, astronomers have found in data from a pair of NASA telescopes.
Estimating the mass of these rings from the amount of light they reflect shows that each of these developing planets is at least the size of a few Earths, according to Carey Lisse, a planetary scientist at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland.
Over the past few decades, using powerful NASA observatories such as the Infrared Telescope Facility in Hawaii and the Spitzer Space Telescope, scientists have found a number of young debris disk systems with thin but bright outer rings composed of comet-like bodies at 75 to 200 astronomical units from their parent stars — about two to seven times the distance of Pluto from our own Sun. The composition of the material in these rings varies from ice-rich (seen in the Fomalhaut and HD 32297 systems) to ice-depleted but carbon rich (the HR 4796A system).
[...] In Fomalhaut and HD 32297, researchers expect that millions of comets are contributing to form the cores of ice giant planets like Uranus and Neptune — although without the thick atmospheres enveloping the cores of Uranus and Neptune, since the primordial gas disks that would form such atmospheres are gone. In HR 4796A, with its warmer dust ring, even the ices normally found in the rings' comets evaporated over the last million years or so, leaving behind core building blocks that are rich only in leftover carbon and rocky materials. "These systems appear to be building planets we don't see in our solar system — large multi-Earth mass ones with variable amounts of ice, rock and refractory organics," Lisse said. "This is very much like the predicted recipe for the super-Earths seen in abundance in the Kepler planet survey."
The supposed exoplanets could also be called "massive solid planets" or "mega-Earths".
Infrared Spectroscopy of HR 4796A's Bright Outer Cometary Ring + Tenuous Inner Hot Dust Cloud
(Score: 3, Interesting) by Fluffeh on Wednesday October 25 2017, @03:49AM (3 children)
Actually, although this sort of volcanic activity can lead to simple life - it is unlikely to create more complex life as the energy density (availability) is not high enough.
Here's an interesting paper if you want to do some extra reading: http://www.pnas.org/content/111/35/12628.full [pnas.org]
Here's a section that talks about energy density:
(Score: 2) by Arik on Wednesday October 25 2017, @04:07AM (2 children)
If laughter is the best medicine, who are the best doctors?
(Score: 2) by Fluffeh on Wednesday October 25 2017, @04:43AM (1 child)
Certain parts of the body require a LOT of energy to function. Our brains, as small as they are compared to the rest of the body account for about 20% of the total energy we use. Additionally, while it can be theorized that with a smaller amount of energy to use, evolution creates life that uses it sparingly (such as animals that move slower for example - like the Sloth) - but it just makes it less likely.
I'm not saying it is impossible - if the universe is infinite, then it's certainly happening somewhere, just the chances of it happening in a particular place is small.
The other thing you need to think about from a biological point of view, is that there are vast amounts of various extremophiles here on earth - all manner of things that lives in amazing environments from ultra saline water to radioactive bars in reactors - but these have ADAPTED from life that already existed. If you had a planet where the ONLY environment was plutonium bars in water, the those things just wouldn't pop into existence one day. You have to have a certain set of conditions for the super primitive life to get a start, then you can wind up the difficulty levels so to speak.
(Score: 2) by Arik on Wednesday October 25 2017, @05:41AM
Anyway my point wasn't about the likelihood but about the shape it might take, and I do like that sloth idea.
Perhaps small sloth-like beings, with dense muscles and opposable thumbs, for climbing in lava vents rather than trees so I imagine thickly padded palms. Perhaps with heads of Organian proportions.
If laughter is the best medicine, who are the best doctors?