Science & Tech · Space · 11 hrs ago
Webb finds evidence of a thick atmosphere on lava planet TOI-561 b
Webb observations suggest TOI-561 b still has a thick atmosphere, even though its close orbit exposes it to intense heat and radiation.
The rocky planet is about 280 light-years away and completes an orbit in roughly 10.7 hours.
Its day side is likely covered by molten rock, while its night side always faces away from its star.
The planet’s day side is cooler than bare rock should be, and measurements show its night side is warm enough for some heat to reach it.
Researchers estimate that TOI-561 b reflects about 74% of the starlight that hits it, which molten rock alone cannot explain.
Their observations and climate simulations point to reflective material above the surface, including mineral clouds.
If the interpretation holds up, the planet challenges ideas about how easily close-orbiting rocky worlds lose their atmospheres; the atmosphere is not livable.
NASA’s James Webb Space Telescope found evidence that the scorching rocky planet TOI-561 b has a thick atmosphere.
The observations also suggest that something above the planet’s surface reflects about 74% of the starlight that hits it.
The planet’s day side measured about 3,200°F (2,050 K), cooler than the estimated 5,300°F (3,200 K) for bare rock without an atmosphere.
TOI-561 b is about 280 light-years away and is not livable.
Researchers say the findings challenge expectations that intense radiation would have stripped the planet’s atmosphere billions of years ago.
- Who
- An international research team led by Samuel Boucher of the Université de Montréal conducted the study.
- What
- Webb observations suggest TOI-561 b has a thick atmosphere and reflective material above its surface.
- When
- The findings were reported on November 1, 2026. The observations covered a 37-hour stretch.
- Where
- TOI-561 b, about 280 light-years away, orbiting its star.
- Why
- The observations suggest the planet’s atmosphere helps explain why its day side is cooler than bare rock would be, while reflective material sends much of the starlight away.
This story does not have two clearly opposing sides.
A study led by Johanna Teske found that TOI-561 b’s day side was too cool for bare rock or an atmosphere made only of rock vapor.
Webb observations covered the planet’s orbit, during which it passed behind its star four times.
Earth.com reported that Webb observations indicated TOI-561 b has a thick atmosphere.
- Distance
- About 280 light-years
- Orbital period
- About 10.7 hours
- Day-side temperature
- About 3,200°F (2,050 K)
- Bare-rock estimate
- About 5,300°F (3,200 K)
- Reflected starlight
- About 74% of the light that hits the planet
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What people are saying
Our discovery challenges current theories
We would expect a heavily irradiated rocky planet like TOI-561 b to have lost its atmosphere billions of years ago.