The Webb Space Telescope has found no evidence of an atmosphere at one of the seven rocky, Earth-sized planets orbiting another star.

Scientists said Monday that doesn’t bode well for the rest of the planets in this solar system, some of which are in the sweet spot for harboring water and potentially life.

“This is not necessarily a bust” for the other planets, Massachusetts Institute of Technology astrophysicist Sara Seager, who wasn’t part of the study, said in an email. “But we will have to wait and see.”

The Trappist solar system — a rarity with seven planets about the size of our own — has enticed astronomers ever since they spotted it just 40 light-years away. That’s close by cosmic standards; a light-year is about 5.8 trillion miles. Three of the seven planets are in their star’s habitable zone, making this star system even more alluring.

The NASA-led team reported little if any atmosphere exists at the innermost planet. Results were published Monday in the journal Nature.

The lack of an atmosphere would mean no water and no protection from cosmic rays, said lead researcher Thomas Greene of NASA’s Ames Research Center.

As for the other planets orbiting the small, feeble Trappist star, “I would have been more optimistic about the others” having atmospheres if this one had, Greene said in an email.

If rocky planets orbiting ultracool red dwarf stars like this one “do turn out to be a bust, we will have to wait for Earths around sun-like stars, which could be a long wait,” said MIT’s Seager.

Because the Trappist system’s innermost planet is bombarded by solar radiation — four times as much as Earth gets from our sun — it’s possible that extra energy is why there’s no atmosphere, Greene noted. His team found temperatures there hitting 450 degrees Fahrenheit (230 degrees Celsius) on the side of the planet constantly facing its star.