Elias 2-24 b is reported as the youngest planet yet found outside the Solar System: the team that confirmed it estimates it is no more than about a million years old. It orbits a young star about 136 parsecs (roughly 440 light-years) away in the Ophiuchus star-forming region, and it is still embedded in the protoplanetary disk it formed from. A protoplanetary disk is the flattened ring of gas and dust that surrounds a newborn star and supplies the raw material for planets.
The planet was confirmed in 2026 by a team led by A. Bernardi of Diego Portales University in Chile. Keck Observatory's NIRC2 camera, which uses a coronagraph to block the glare of the star, first recorded a faint signal from the system in 2018, but not enough to call it a planet. Re-processing those archived images with newer techniques, and adding a second Keck observation from 2020, recovered the source in the place where earlier studies with ESO's Very Large Telescope and the ALMA radio telescope array had reported a candidate. The team also showed it moves across the sky with the star, so it is not a distant background object.
What makes it notable is where it sits. ALMA images show the disk split by dark rings called gaps, and Elias 2-24 b lies inside one of them, about 55 astronomical units from its star (one astronomical unit is the Earth–Sun distance). Astronomers have long suspected that young planets carve such gaps, and this is one of the clearest cases of a planet found in one. The authors argue it formed by core accretion, where a solid core grows first and then pulls in gas, and that it shows a giant planet can form this way about 50 astronomical units out within roughly a million years.
Much is still uncertain. Ages for stars this young are notoriously hard to pin down, and the authors note the system may be even younger. Comparing the planet's brightness with models gives a mass between 1.9 and 4.0 times Jupiter's, but that range ignores the extra light from material falling onto the planet; because it is probably still accreting vigorously, the team favours the lower end. Its temperature is estimated at roughly 1,100 to 2,000 kelvin. The two Keck images are too close in time to show the planet moving along its orbit, so its orbit is not yet measured, and the team hopes future observations will tighten its mass and reveal more about its atmosphere.