Water-worlds are common: Exoplanets may contain vast amounts of water
Scientists have shown that water is likely to be a major component of those exoplanets (planets orbiting other stars) which are between two to four times the size of Earth. It will have implications for the search of life in our Galaxy. The work is presented at the Goldschmidt conference in Boston.
[...] [A] new evaluation of data from the exoplanet-hunting Kepler Space Telescope and the Gaia mission indicates that many of the known planets may contain as much as 50% water. This is much more than the Earth's 0.02% (by weight) water content. [...] Scientists have found that many of the 4000 confirmed or candidate exoplanets discovered so far fall into two size categories: those with the planetary radius averaging around 1.5 that of the Earth, and those averaging around 2.5 times the radius of the Earth.
[...] "We have looked at how mass relates to radius, and developed a model which might explain the relationship," said [lead researcher] Li Zeng. The model indicates that those exoplanets which have a radius of around x1.5 Earth radius tend to be rocky planets (of typically x5 the mass of the Earth), while those with a radius of x2.5 Earth radius (with a mass around x10 that of the Earth) are probably water worlds."
"This is water, but not as commonly found here on Earth," said Li Zeng. "Their surface temperature is expected to be in the 200 to 500 degree Celsius range. Their surface may be shrouded in a water-vapor-dominated atmosphere, with a liquid water layer underneath. Moving deeper, one would expect to find this water transforms into high-pressure ices before we reaching the solid rocky core. The beauty of the model is that it explains just how composition relates to the known facts about these planets." Li Zeng continued, "Our data indicate that about 35% of all known exoplanets which are bigger than Earth should be water-rich. These water worlds likely formed in similar ways to the giant planet cores (Jupiter, Saturn, Uranus, Neptune) which we find in our own solar system. The newly-launched TESS mission will find many more of them, with the help of ground-based spectroscopic follow-up. The next generation space telescope, the James Webb Space Telescope, will hopefully characterize the atmosphere of some of them. This is an exciting time for those interested in these remote worlds."
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NASA Retires Kepler Space Telescope
After nine years in deep space collecting data that indicate our sky to be filled with billions of hidden planets - more planets even than stars - NASA's Kepler space telescope has run out of fuel needed for further science operations. NASA has decided to retire the spacecraft within its current, safe orbit, away from Earth. Kepler leaves a legacy of more than 2,600 planet discoveries from outside our solar system, many of which could be promising places for life.
"As NASA's first planet-hunting mission, Kepler has wildly exceeded all our expectations and paved the way for our exploration and search for life in the solar system and beyond," said Thomas Zurbuchen, associate administrator of NASA's Science Mission Directorate in Washington. "Not only did it show us how many planets could be out there, it sparked an entirely new and robust field of research that has taken the science community by storm. Its discoveries have shed a new light on our place in the universe, and illuminated the tantalizing mysteries and possibilities among the stars."
(Score: 0, Funny) by Anonymous Coward on Sunday August 19 2018, @08:41AM (1 child)
On the Front Page, how long? No comments. Nada. Zilch. Bupkiss. Zenzen arimasen. Isn't it time for a nice aristarchus submission?
(Score: 3, Touché) by takyon on Sunday August 19 2018, @10:23AM
No water world large enough to contain your salty tears.
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(Score: 2) by maxwell demon on Sunday August 19 2018, @07:44PM (6 children)
Maybe that's one solution to the Fermi paradox?
Life as we know it certainly needs water. But if the planets that contain water usually are covered with it, then those planets, even though they may evolve life, never will evolve land-based life (since there's no land for it to evolve on), which could effectively prevent evolution of sophisticated object manipulators (in our case, hands), which in turn implies no technology, and thus no interstellar communication (not to mention that building a radio telescope on water would be quite a challenge also for us).
So maybe Earth is the outlier in having enough water to support life, but not enough to cover the complete surface. As far as I know, the moon is assumed to have formed by a collision between early Earth and another body. Maybe in that collision Earth lost most of its water, leaving it in the current state.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2) by aristarchus on Sunday August 19 2018, @10:02PM (4 children)
Hmm, would not any sufficiently intelligent life-form develop tech for dealing with it's "unfortunate" dependence upon water? The only difference between them and humans would be that humans need to travel in little capsule of a mixture of gases, while the aquatic space-farers would need capsules of the proper mixture of liquids.
And as for the "sophisticated object manipulators", you should be thinking in terms of cephalopods or crustaceans, not fish or silly dolphins!
(Score: 2) by maxwell demon on Monday August 20 2018, @05:56AM (3 children)
With the ocean floor at depths compared to which even the Mariana Trench is shallow, I strongly doubt that crustacean-like animals would evolve.
And even assuming that intelligent life able to make tools would evolve near the ocean floor, such a water world would lack the materials to build any technology to even safely reach the upper ocean (remember: the pressure difference between deep sea and shallow sea is huge compared to the pressure difference between atmosphere and space), because those materials would be buried under kilometer-thick layers of dense ice.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2, Insightful) by aristarchus on Monday August 20 2018, @06:36AM
Now this is where I disagree, on a speculative basis. I could be that the barriers posed to an aquatic life form could never surmount the obstacles to exploring inter-planetary, or even inter-stellar, space. But on the other hand, we terrestrials assuming the limits we assume about the aquatics is nearly equivalent to the editors of SoylentNews assuming that all aristarchus submissions are incapable of trans-galactic transmission, or of getting more than two hundred comments. Think below the ice. Think slow, think hard. We are the ones we are waiting for to communicate across the vast water-deserts of space. Can you hear me now? See, this is why we cannot have white supremacism, whitey don't do space.
(Score: 2) by urza9814 on Monday August 20 2018, @03:29PM (1 child)
Forget about high technology to get out of the ocean and fly to the stars...how do you cook a steak under the sea?
My understanding is that cooking was a pretty big deal in the development of our species -- it dramatically reduced the energy required for digestion, which freed that energy to be used by our brains. In addition to reduction in disease and such. Perhaps it's possible to develop technological societies without that step, but we certainly don't have any examples of that yet. And it also seems at least plausible that such a sudden change could be necessary in order to develop brains that have the time and energy to contemplate something other than basic survival. One creature's brains had to evolve dramatically faster than others' in order to escape the arms race that is evolution.
One thing that water is really good at is distributing energy. One thing that intelligent life and technology in particular really depends on is concentrations and gradients of energy. Can that contradiction be overcome? Maybe. Does it make things harder? Almost certainly.
(Score: 0) by Anonymous Coward on Tuesday August 21 2018, @07:10AM
It involves the intelligent use of enzymes, as opposed to crude temperature modulation. Think of it as the "gazpacho of the sea".
(Score: 0) by Anonymous Coward on Monday August 20 2018, @12:36PM
Fire.
Intelligence is one thing -- squid have been around longer than chimps (had more time to evolve), and can be smarter than chimps on certain tests including manual dexterity. But without the ability to have fire, there's no way to make the kinds of technology that lead to industry and a scientific revolution. It's all about energy and learning how to control it. You need combustion, otherwise you're limited to muscle power.
(Score: 2) by arslan on Sunday August 19 2018, @10:41PM (1 child)
Darn I was so excited reading the title, I was imagining a scantily clad Jeanne Tripplehorn on a floating shanty looking for dirt. The rest of the article was anti-climactic.
(Score: 2) by takyon on Monday August 20 2018, @02:59AM
These worlds are gonna make you wet.
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