New observations find no sign of helium in a much-studied exoplanet’s atmosphere; the presence of helium may have indicated that the planet’s atmosphere was being blown away.

Researchers have observed and characterized the largest collection of “dipper” stars — those that dim by 10–50% — finding that these stars’ spectral signatures hint at the presence of surrounding disk material.

Researchers calculated the ability of various solar system objects to gravitationally bend light from distant objects, which will be necessary to know before conducting high-precision astrometry.

Type Ia supernovae aren’t always the result of a white dwarf accreting material from a stellar companion, and the huge ejecta mass of a recent explosion suggests a merger of two white dwarfs instead.

Spectra of eight planetary nebulae — the beautiful, short-lived nebulae formed when low- and intermediate-mass stars evolve off the main sequence — yield new chemical abundance measurements.

A study of two of six potential landing sites for Artemis astronauts suggests that the two sites are traversible but contain large boulder fields, areas of exposed impact crater ejecta, and permanently shadowed regions.