How many planets are there in the nearby Centauri galaxy?

Proxima centauri is the nearest neighbor of the sun and one of the most deeply studied low-mass stars. Astronomers finally confirmed the existence of two exoplanets, Proximity B and C, orbiting proxima centauri Centauri.

Photo: The artist's photo shows that the neighboring star B orbits Centauri, which is only 4.23 light years away from us and is the closest star to the solar system. The binary star Alpha AB Centauri also appears in the image between this exoplanet and its neighboring star.

Proxima centauri, the smallest member of the Centauri galaxy, is a M5.5 star, 4.244 light years away from the Southern Centauri.

The measured radius of this star is 14% of the sun's radius, its mass is about 12% of the sun's, and its effective temperature is only 3050K(2777 degrees Celsius or 503 1 Fahrenheit).

The brightness of proxima centauri is 1 1,000 times lower than that of the sun, which is invisible to the naked eye even at close range.

Its rotation speed is very slow, 83 days, and its long-term activity cycle is about 7 years. Its livable area ranges from 0.05 to 0.1au.

Earth-mass neighboring planet B was discovered in 20 16 by astronomer GuillemAnglada-Escud of Queen Mary University in London. The doctor and his collaborators discovered for the first time.

This planet is located in a livable area of proxima centauri, and theoretically liquid water can exist.

It is an important task to confirm the existence of neighboring star B, which is one of the most interesting planets known in the solar system. The universities of Rias and Laguna, Ghana, and the astronomer Alejandro Suarez Maskale? Dr. o said. Published in? Astronomy and astrophysics? The lead author of a paper in a magazine.

Maskale? The existence of Proxima b, a high-resolution spectrometer installed on ESO very large telescope, was confirmed by independent measurements obtained by Dr O and his colleagues using ESPRESSO (Eicher Spectrometer for observing exoplanets and stabilizing spectra).

Their results show that the minimum mass of neighboring star B is 1. 17 times the mass of the earth (previously estimated to be 1.3 times the mass of the earth), and it only revolves around the star in 1 1.2 days.

ESPRESSO makes it possible to measure the mass of planets, and its accuracy is more than one tenth of the mass of the earth. This is completely unheard of. ? Nobel Prize winner, honorary professor of Geneva University, all espresso machines? Architect? Michelle? The mayor said.

The artist's impression of proxima centauri system.

Earlier this year, Dr. Mario Damaso of the Italian National Institute of Astrophysics and his colleagues announced that they might have discovered a super-Earth exoplanet near proxima centauri.

Astronomers use radial velocity observation to infer a candidate planet named Proxima c, which revolves around the star every 1907 days at a distance of 1.5 AU. However, its existence is uncertain.

In another study, George? From the McDonald's Observatory and the University of Texas at Austin? Dr Benedict and Barbara? Dr MacArthur re-examined the 25-year-old Hubble telescope's research on proxima centauri.

When we first studied proxima centauri in 1990, we only studied planets with orbital periods of 1000 Earth days or less. We didn't find it. ? Dr. Benedict said.

We have now re-examined these data to check for signs that the orbital period of the planet is getting longer. ?

In fact, the research team found a planet with an orbital period of about 1 907 days in the archived Hubble data.

This is an independent confirmation of the existence of proxima centauri C.

Description: These images were taken by the spherical instrument on ESO Very Large Telescope, showing the candidate optical counterpart of proxima centauri C (red circle). The background will also be displayed.

Soon after, Dr. Raffaele Gratton of INAF and his colleagues used the SPHERE (Spectral High Contrast Extraterrestrial Planetary Research) instrument to take pictures of several points in the planetary orbit on the ESO very large telescope.

Then, Dr. Benedict and Dr. MacArthur combined the findings of these three studies: Hubble astrometry, Dr. Damaso's radial velocity study and Dr. graton's image to improve the quality of proxima centauri C.

They found that the mass of this planet is about seven times that of the earth.

Dr Benedict said: Basically, this is a story about how old data can be very useful in obtaining new information. ?

This is also a story, which shows that if you are an astronomer, it will be difficult to retire because it is very interesting! ?

Dr Benedict and Dr MacArthur presented their research results at the 236th meeting of the American Astronomical Society (AAS) on June 2nd.