Astronomers discover strange twin planets might be water worlds

[Judi Lynn]

By Meghan Bartels
published about 19 hours ago

Two planets found by NASA's retired Kepler Space Telescope may be made mostly of water, according to new research.

The two exoplanets, dubbed Kepler-138c and Kepler-138d, orbit a star located about 218 light-years away from Earth in the constellation Lyra. Scientists intrigued by 2014 data from the Kepler Space Telescope decided to revisit the two planets using the Hubble Space Telescope and NASA's retired Spitzer Space Telescope in hopes of better understanding the distant worlds and what they're made of. And surprisingly, the answer might be mostly water.

"We previously thought that planets that were a bit larger than Earth were big balls of metal and rock, like scaled-up versions of Earth, and that's why we called them super-Earths," Björn Benneke, a planetary astrophysicist at the Université de Montréal in Canada and a co-author on the new research, said in a statement.

"However, we have now shown that these two planets, Kepler-138c and d, are quite different in nature: a big fraction of their entire volume is likely composed of water," he said. "It is the first time we observe planets that can be confidently identified as water worlds, a type of planet that was theorized by astronomers to exist for a long time."

More:
https://www.space.com/exoplanets-potential-water-worlds-discovered

[Javaman]

1. "paper! have you ever seen paper!"

[GreenWave]

2. But we need continents. Not true says the dolphin.

Is our Earth II larger? If not we probably have to avoid if they are too much bigger.

[PoindexterOglethorpe]

3. This is in part why we have not found other intelligent species.

They might live on a very different kind of planet, such as one which has even less dry land than ours does.

Or their planet might be covered with clouds of some kind (sort of like Venus, but not so hot) and so they have no idea what else is out there.

Or they might be on a planet like Europa, covered by ice, so again they never see the stars.

Or perhaps their vision is quite different from ours and, you guessed, it, never see the stars.

And that's not even thinking about the very distant chance that two civilizations would overlap in time and actually be close enough to make contact.