Search & fact check with cited sources for What did astronomers confirm about LHS 1140b, and why is that significant?

Why this is significant:

• First-of-its-kind detection. While astronomers have detected atmospheres on many gas giants, this is the first time an atmosphere has been confirmed on a rocky, temperate exoplanet that orbits in the habitable ("Goldilocks") zone — the region where liquid water could exist on the surface .
• Sets up a search for life. The planet is rocky, at the right temperature, and now known to have an atmosphere — three of the essential ingredients scientists believe are needed to support life. As co-author David Charbonneau put it, "All the pieces that we think are essential for life are present" .
• Helium as a telltale sign. The Magellan Clay telescope in Chile detected helium escaping from the planet. Because the planet is old enough that it should have lost all primordial helium long ago, the ongoing helium signal means the planet must be replenishing it — strong indirect evidence of a stable, sustained atmosphere rather than a bare rock .
• JWST follow-up is next. LHS 1140 b is a selected target for the James Webb Space Telescope's Rocky Worlds Program. Observations over the next 4–5 years will look for water and carbon dioxide, which could confirm a stable atmosphere and further assess habitability .

The discovery marks a major milestone in the decades-long effort to find a potentially habitable world beyond our solar system. Astronomers caution there is no evidence of life yet, but the planet now represents the best candidate we have for detailed follow-up .