A Waterfall of Planets: The Mystery of the Vanishing Water Worlds ⚡ экспресс
Planets fall into two types: rocky (like Earth) and water worlds. Scientists found that a size gap appears between them if water planets lack a thick hydrogen atmosphere. It turns out most sub-Neptunes are water giants, but about 20% still hold a touch of hydrogen. The whole thing looks like a waterfall: the planet count drops sharply at a certain border.
The Kepler telescope William Borucki's caught the faint twinkling of distant stars and discovered thousands of planets around other suns. Among them gapes a gap: almost no worlds sized between rocky balls and puffy water giants. This 'radius valley' was explained by a new model: planets initially divide into rocky and water ones. Water worlds with a steam atmosphere fill the gap, but at three times Earth's size they abruptly cut off — like a stream plunging over a waterfall.
Upon reaching a critical mass, such a planet captures hydrogen and helium and becomes a gas giant. Large water worlds simply don't get a chance to appear — they transform earlier. But inside them lies a surprise: water under immense pressure turns into hot ice — solid but scorching. Light measurements from Kepler show that the oceans there have no bottom. And although such water worlds are common in the galaxy, our Solar System is just one possible recipe.
🎯 On water planets, water turns into hot ice under incredible pressure — a solid substance that remains red-hot. So the oceans there can be liquid on top and icy deep down at the same time.
🎬 In 'Interstellar,' the characters visit Miller's planet, covered by a shallow ocean. But real water worlds are more like giant droplets without a solid surface, far deeper than any Earthly seas.