Want to stay on top of all the space news? Follow @universetoday on Twitter
The nearest star system is Alpha Centauri. With the unaided eye, this looks like a very bright star, seen only from the southern hemisphere. But with a good telescope, you can actually see that Alpha Centauri is really two stars. They’re known as Alpha Centauri A and B. And with a really good telescope, there’s a third red dwarf star in the system, known as Proxima Centauri. Proxima Centauri is the closest star to Earth, and so the distance to nearest star Proxima Centauri is 4.243 light years away.
Proxima Centauri is a red dwarf star. It has only 1/8th the mass of the Sun, and a diameter of only 1/7th the Sun. It seems to be on a highly elliptical orbit around the two larger stars in the Alpha Centauri system, taking about 500,000 years to complete a single orbit. From here on Earth, we see Proxima Centauri about 4 times the width of the Moon away from Alpha Centauri AB.
Proxima Centauri has been the nearest star for about 32,000 years, and it will hold this record for another 33,000 years. It will make its closest approach to the Sun in about 26,700 years, getting to within 3.11 light-years of Earth. After 33,000 years from now, the nearest star will be Ross 248.
We’ve written many articles about Alpha Centauri for Universe Today. Here’s an article about how to search for planets around Alpha Centauri, and here’s an article about how Proxima Centauri might not be part of the system.
Here’s a cool article from NASA about the nearest star.
We’ve recorded an episode of Astronomy Cast about what it might take to travel to the closest star. Listen here, Episode 145: Interstellar Travel.