Newfound 'baby' planet smashes record for youngest known world

Astronomers have discovered a planet that is just a million years old and is considered the youngest known planet. Dubbed Elias 2-24 b, the baby world is still embedded in a disk of dust and gas that surrounds its young host star. This record-breaking planet was confirmed using data from NASA-funded archives and observed with the coronagraph at the W. M. Keck Observatory in Hawaii, a partnership with NASA.

Professor Lucas Cieza of the Instituto de Estudios Astrofísicos in Chile, a co-author of the paper detailing the results, noted that previous record holders for the youngest known planet were more than five million years old. These planets were discovered orbiting the stars PDS 70 and WISPIT 2. Elias 2-24 b demonstrates that even our best planet-formation models are still lacking some essential processes.

The team behind the discovery, led by doctoral candidate Andrea Bernardi from the Universidad Diego Portales in Chile, analyzed archival observations of seven stars observed using the Keck Observatory's coronagraph. Each of these stars has a debris disk filled with dust, gas, and chunks of ice and rock, and the presence of gaps or structures in the disk hints at the possibility of planets forming.

The team searched for fainter planets embedded in these dusty disks and found Elias 2-24 b within a prominent gap, supporting the leading theory of giant planet formation.

Astronomers have long debated the formation of exoplanets, particularly those in their early stages, as observing them is difficult due to the dust that shrouds them. Most discovered exoplanets are billions of years old and very close to their stars, making it challenging to study their newborn stages. Finding and studying more baby planets like Elias 2-24 b will help refine current planet-formation models.