Four "miniature Earths" revealed, may be 10 billion years old

(NLDO) - Around an ancient star less than 6 light years from Earth, scientists have discovered signs of 4 rocky planets.

Using the MAROON-X instrument on the Gemini North telescope of the International Gemini Observatory and the ESPRESSO instrument on the Very Large Telescope of the European Southern Observatory (ESO), American scientists discovered four "mini-Earths" around Barnard's star.

Graphic of four "mini-Earths" orbiting Barnard's star - Photo: NOIRLab/NSF/AURA

Barnard's Star is an old celestial body, estimated to be 10 billion years old, and is a faint red dwarf.

Also known as Gliese 699 or GJ 699, Barnard is located in the constellation Ophiuchus, invisible to the naked eye despite being less than 6 light years from Earth.

According to researcher Ritvik Basant from the University of Chicago (USA), the four planets discovered around Barnard are all rocky and have a mass of only about 20-30% of the Earth's mass.

Therefore, the authors call them "mini-Earths". Usually the planets are only slightly younger than their parent star, so they are also extremely old planets.

For comparison, our Earth is about 4.54 billion years old, orbiting its parent star, the Sun, which is about 4.6 billion years old.

The four new planets are also among the smallest exoplanets ever observed by humanity.

Of the four, three are showing definite signs, while the other is a bit fainter. It doesn't show up in Gemini North's data, but only shows up under the more powerful "eye" of Very Large, according to Sci-News.

Writing in the Astrophysical Journal Letters, the authors said the identification of these tiny rocky planets was a major breakthrough in astronomical observation.

These four planets are also proof that the potential of the world's current telescopes is still very large, especially in searching for "copies" of Earth.

Source: https://nld.com.vn/bon-tieu-trai-dat-lo-dien-co-the-da-10-ti-nam-tuoi-196250314110700816.htm