Writing in the latest issue of astronomy and astrophysics, an international team of researchers says they have confirmed once again that an Earth-sized planet orbits the nearest star to the sun, “Proxima b”, which is 1.17 times the mass of Earth and is located in the habitable zone of its star, with a cycle of 11.2 days.
Four years ago, the HARPS spectrometer first discovered the “neighboring star b”. This time, the scientists confirmed the existence of the “neighborb b” by using the ESPRESSO spectrometer on the Very Large Telescope (VLT) in Chile, the most accurate spectrometer to date, to measure the unprecedented radial velocity of neighboring stars (4.2 light-years from the sun). The latest measurements show that the minimum mass of “neighbor edg” is 1.17 times the Mass of the Earth (previously estimated at 1.3). “It is important to confirm the existence of ‘next star b’, one of the most interesting planets around the sun,” said lead author Alexander Mascarinho. “
Studies have shown that although the distance between “neighbored star b” and its star is only 1/20 of the distance between the Earth and the sun, it receives the same amount of energy as the Earth, so its surface temperature is appropriate, which may mean that water (if present) is liquid in some places, so life is expected to flourish there.
However, the researchers also point out that there is still a long way to go to prove that life can survive on its surface. In fact, the next star is an active red dwarf star that continues to bombard its planet with X-rays, which receive 400 times more X-rays than Earth.
Researcher Christopher Lewis said: “Does the planet have an atmosphere that protects itself from these deadly radiations?” If such an atmosphere exists, does it contain chemical elements (such as oxygen) that promote the growth of life? How long have these advantages been around? We will answer these questions with the help of future facilities. These facilities include RISTRETTO spectrometers designed to detect light emitted by ‘adjacent star b’. “
ESPRESSO also brought a surprise: the team found evidence of a second signal in the data. “If this signal originated on a planet, then the mass of another potential planet that accompanies ‘neighbor b’ would be less than one-third of Earth’s mass, which would be the largest asteroid ever measured using radial velocity,” said Francisco Pepe of the University of Geneva in Switzerland, who led ESPRESSO. (Reporter Liu Xia)