A new analysis of supernovae observations hints that dark energy may change strength over time. It could mean we need to recalculate the universe's fate.
NASA's Chandra X-ray Observatory has found a baby exoplanet that is slowly losing its atmosphere and shrinking as it is pummeled by radiation from its star.
It's highly unlikely the interstellar comet 3I/ATLAS is an alien spacecraft. However, here are things scientists would look for to detect an alien probe.