Scientists have identified one of the oldest planetary systems ever discovered. The planetary system has a rocky planet called toi-561b that orbits a 10 billion year old star. The star is more than twice the age of the sun, which researchers say suggests planets have formed since the early days of the universe.
Ancient planets are less dense because they have less heavy elements such as metals. Heavy elements are produced inside stars, because stars explode into supernovae as they age. Supernova explosions distribute elements into the surrounding space, which are included in the formation of planets. In the early universe, star explosions occurred less frequently, resulting in less heavy elements in the interior of planets.
Toi-561b is one of the oldest rocky planets ever discovered. The presence of toi-561b proves that rocky planets have been formed almost 14 billion years ago, according to researcher Lauren Weiss. The planet was discovered using data from NASA's Tess mission and confirmed by the W.M. Keck Observatory in Hawaii.