Four "mini-Earths" have emerged, possibly 10 billion years old.

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

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

Graphic image of 4 "mini-Earths" orbiting Barnard's star - Image: NOIRLab/NSF/AURA

Barnard's star is an ancient 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 and is 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 planets and have masses of only about 20-30% of Earth's mass.

Therefore, the authors call them "mini-Earths." Often, these planets are only slightly younger than their parent star, making them extremely old planets.

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

These four new planets are also among the smallest exoplanets that humanity has ever observed.

Of the four, three planets showed clear signs, while the remaining one was slightly fainter. It didn't appear in the Gemini North data but only revealed itself under the more powerful "eye" of Very Large, according to Sci-News.

Writing in Astrophysical Journal Letters, the authors stated that identifying these tiny rocky planets represents a major breakthrough in astronomical observation.

These four planets also demonstrate the immense potential of the world 's current telescopes, especially in the search for "Earth clones."

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