Wet-and-wild water worlds could kind beneath stress

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From:
Springer Nature

Planetary science: Water worlds would possibly kind beneath stress (N&V)

Some exoplanets could produce water throughout their formation through reactions between rocks and hydrogen, in response to new analysis in Nature. The findings supply perception into why some exoplanets have water on their floor.

The presence of water is a key ingredient in figuring out a planet’s habitability, and water has been thought to kind by way of condensation from area as ice or snow at low temperatures. This course of has usually been noticed in exoplanets between the dimensions of Earth and Neptune which might be situated far-off from their host star. However, NASA’s Kepler mission has discovered exoplanets between the sizes of Earth and Neptune with liquid water that orbit near their solar, calling this course of into query.

Harrison Horn and colleagues simulated reactions that would happen throughout planetary formation by heating rock samples with pulsed lasers in a high-pressure laboratory atmosphere. They noticed that hydrogen reacted with melted silicates from the rocks to launch oxygen, which then bonded with leftover hydrogen to kind water molecules. The authors recommend that this response may most certainly happen within the high-pressure and high-temperature core–envelope boundary of exoplanets, the place the denser, rocky core meets an outer envelope of gaseous parts. They recommend that this water-generating response may happen over billions of years on some exoplanets extra huge than Earth. However, the velocity of those reactions is decided by how a lot hydrogen is accessible and the way scorching the core–envelope boundary is.

The authors observe that these findings problem the pre-existing information on how water types on exoplanets of sure sizes and at sure distances from their host star.