Solar System

Found: A Neptune-sized planet with sulfur-rich clouds and a watery atmosphere

Found: A Neptune-sized planet with sulfur-rich clouds and a watery atmosphere

Scientists peering at a “warm Neptune” roughly 430 light-years away have discovered far less water in the gassy planet’s atmosphere than they expected — which puts it at odds with the ice giants in our own solar system.

The atmosphere of HAT-P-26b, described in the journal Science, runs counter to some long-standing theories about planetary development and could help scientists understand the diversity of worlds beyond our own.

“This is providing insight into how planets could form and evolve different than our solar system,” said lead author Hannah Wakeford, an astrophysicist at NASA Goddard Space Flight Center. “And that really tells us about how unique or easy it is to form...

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