A planet still growing inside the dusty remains of its birth has broken an important record. Astronomers have confirmed Elias 2-24 b as the youngest known planet, with an age of less than a million years. That is remarkably young on a cosmic clock. Earth is about 4.5 billion years old, while many of the exoplanets found by astronomers are billions of years old. Elias 2-24 b is different.
Scientists are seeing it while its planetary neighborhood is still taking shape. The planet orbits Elias 2-24, a young star about 450 light-years from Earth. It is roughly as massive as Jupiter and remains inside the disk of gas and dust that surrounded the star after its birth.
