New research from ETH Zurich challenges the long-held “follow the water” rule in the search for extraterrestrial life. Scientists argue that a planet’s habitability depends on a narrow chemical balance during core formation, preserving phosphorus and nitrogen in its mantle. Earth falls within this rare “Goldilocks” range, potentially making truly life-supporting worlds far rarer than assumed.

A rare event was observed as comet 41P/Tuttle-Giacobini-Kresák dramatically slowed its rotation and then spun in the opposite direction. This extreme change in spin, driven by material jets, was captured by Hubble and Swift telescopes. Astronomers believe this process may explain the rarity of smaller comets.