Astronomers Discover Youngest Known Planet Elias 2-24 b

Astronomers have confirmed Elias 2-24 b as the youngest known planet, with an estimated age of less than 1 million years as of 17 September 2026. The planet orbits Elias 2-24, a star located about 450 light-years from Earth, and it remains embedded in the dusty gas-and-debris disk from which it formed.

Discovery and Location

Elias 2-24 b lies in a prominent gap within the protoplanetary disk of its host star. The planet has a mass comparable to Jupiter, which places it among gas giant planets in size and composition.

Planet Formation and Accretion

The planet is still accreting material from its surrounding disk. Protoplanetary disks are rotating structures of gas, dust, and debris around young stars, and they are the sites where planets form.

Observational Methods and Instruments

The confirmation used data from NASA-funded archives and observations from multiple telescopes. These included the W. M. Keck Observatory in Hawaii, the Atacama Large Millimeter/submillimeter Array in Chile, and the European Southern Observatory’s Very Large Telescope in Chile.

Important Facts for Exams

• Elias 2-24 b was first inferred from a gap in the disk in 2017 before direct confirmation later.
• Andrea Bernardi, a doctoral candidate at Universidad Diego Portales in Chile, led the team that confirmed the planet.
• PDS 70 and WISPIT 2 are other young planetary systems used in planet-formation studies.
• The Nancy Grace Roman Space Telescope carries a coronagraph for direct imaging of faint objects near bright stars.

Scientific Context

The discovery is relevant to studies of planet formation because planets younger than 1 million years are rare in observational astronomy. The finding adds a data point for the early stages of planetary growth in circumstellar disks.