About six light years from the Sun, the red dwarf named Barnard’s Star is the closest stellar neighbor to our Solar System and the fastest moving star in the night sky. At the same time, its orbit is truly dramatically shaky. This shake can be attributed to his old age.
Researchers are “99%” sure that there is an exoplanet near the Solar System.
It is hoped that the star was born about 10 billion years ago, twice as old as the Sun. However, its mass is only 16% of that of the Sun. But astronomers prefer a different explanation. An article published in the journal Nature, combining 20 years of research, says there is a “99%” chance that the orbit of the Barnard Star will be pulled by a nearby exoplanet. (According to data in the magazine How it works) This planet is roughly three times the size of Earth and covered with glaciers.
Astronomers first noticed this super-Earth (super-Earth means an exoplanet whose mass is larger than Earth’s but smaller than that of ice giants like Uranus and Neptune) for the first time twenty years ago, when they were taking Barnard’s Star velocity measurements. Scientists have noticed that the Barnard Star swings closer to the Solar System every 230 days, then retracts. One possible explanation for this would be a large planet exerting its own gravitational effect on Barnard’s Star as it orbits its parent star. But to say this for sure, more data was required.
Now, after 20 years of observations with telescopes from all over the world, new data have been obtained. An international team of scientists studied more than 700 velocity measurements of Barnard’s Star in a recent study, and they say the most likely explanation for this wobbling in the star’s orbit is a planet orbiting the local star every 233 days.
According to Cristina Rodriguez-Lopez, researcher at the Instituto de Astrofisica de Andalucia, the co-author of the study, the discovery is “a development that strengthens the efforts to search for exoplanets around the closest neighboring stars and the hopes of someday encountering a planet that has the necessary conditions to accommodate life”.