Astronomers have discovered a large planet circling a sun nearby to Earth called Barnard’s Star. Apart from the Alpha Centauri system which consists of three stars and is around 4.3 light years away from us, Barnard’s Star is the next nearest star at 6 light years away.
The potential new planet is thought to be cold and icy and has a size around 3.2 times that of the Earth. It is called Barnard’s Star b and it is currently a “candidate” planet, meaning that more research will be required to confirm its location and status. The planet is believed to lie around 0.4 astronomical units or 37 million miles from Bernard’s Star, which is less than half of the distance between the Earth and the Sun. The planet orbits around the star and completes a rotation every 233 days.
The evidence for the existence of the planet comes from gravitational forces which cause shifts in the light coming from the nearby star and heading towards our Earth. This was tricky to detect because the planet is, relatively speaking, very small as well as being distant, so it required analysis of more than 20 years’ worth of data to find. Another complicating factor is the high speed at which Barnard’s Star moves, as it travels at over 300,000 mph relative to the Sun. It is coming closer to us and it should overtake Alpha Centauri to be the closest star to the Sun in the next 10,000 years.
There has long been speculation that planets could orbit around Barnard’s Star, which is a red dwarf star around one sixth the size of our Sun. At 10 billion years old the star is twice as old as our Sun, and it gives off only three percent of the light that our Sun does, hence the reason Barnard’s Star b will be an icy planet. The estimated temperature on the surface of the planet is -275F, and astronomers predict that the surface will have dim, orange light during the day from the nearby red dwarf.
But don’t get your hopes up about moving to this new planet just yet, as Barnard’s Star b is too far away from its dim star for liquid water to be present on its surface. The findings are published in Nature.