The Oldest Known Planet in the Universe Discovered

Astronomers have found a planet that is believed to be 10 billion years old, which is nearly the age of the universe itself. The object orbits one of the oldest stars in our galaxy, which is located 280 light years from Earth. The Astronomical Journal accepted the article with the research results for publication.

The planet is three times more massive than Earth and 1.5 times the size of it. It revolves around the star named TOI-561 with an orbital period of 10.5 hours. TOI-561 b surface temperature is estimated to be 2,480 Kelvin, and one side of it always faces the local sun. This scientific discovery suggests that rocky planets can exist for a very long time and remain stable.

The planet's density can be compared to that of the Earth. It means that it is composed of light elements. Heavy elements are formed inside the stars and are thrown out into space with their death, including during supernova explosions. Therefore, the oldest stars have low metallicity, meaning that they contain few elements that are heavier than hydrogen. Similarly, any ancient planet also cannot contain many heavy elements.

The existence of old planets increases the chances of a complex life being developed. Vertebrates appeared on Earth no earlier than 500 million years ago, although the age of the Earth is 4.5 billion years.