The Ten Closest Stars to Earth

The_bright_star_Alpha_Centauri_and_its_surroundings-1-.jpg
Alpha Centauri and its surrounding stars. This is a southern-hemisphere star, part of the constellation Centaurus. Digital Sky Survey/NASA

The Sun and its planets live in a somewhat isolated part of the Milky Way, with only three stars closer than five light-years. If we broaden our definition of "nearby", however, there are more stars closer to the Sun than we expect. Our region may be on the outskirts of the Milky Way Galaxy, but that doesn't mean it's alone.  

The Sun

Sunrise over Africa
Günay Mutlu/ Photorgapher's Choice RF/ Getty Images

So, what's the closest star to us? Obviously, the top title holder on this list is the central star of our solar system: the Sun. Yes, it's a star and a very nice one at that. Astronomers call it a yellow dwarf star, and it has been around for about five billion years. It illuminates the Earth in the daytime and is responsible for the Moon's glow in the night. Without the Sun, life would not exist here on Earth. It lies 8.5 light-minutes away from Earth, which translates to 149 million kilometers (93 million miles). 

Alpha Centauri

1280px-Alpha-_Beta_and_Proxima_Centauri.jpg
The closest star to the Sun, Proxima Centauri is marked with a red circle, close to the bright stars Alpha Centauri A and B. Courtesy Skatebiker/Wikimedia Commons.

The celestial neighborhood also contains the Alpha Centauri system. It comprises the closest set of stars, even if their light does take just over four years to reach us. There are actually three all doing a complex orbital dance together. The primaries in the system, Alpha Centauri A, and Alpha Centauri B are about 4.37 light-years from Earth. A third star, Proxima Centauri (sometimes called Alpha Centauri C) is gravitationally associated with the former. It's actually slightly closer to Earth at 4.24 light-years away.

If we were to send a light-sail satellite out to this system, it would likely encounter Proxima first. Interestingly enough, it appears that Proxima may have a rocky planet!  

Are light sails possible? They are, and they could be a reality in astronomy exploration very soon. 

Barnard's Star

Barnard's Star. Steve Quirk, Wikimedia Commons.

the next-closest star is a faint red dwarf about 5.96 light-years from Earth.  It's called Barnard's Star, after American astronomer E.E. Barnard. It was once hoped that it might contain planets around it, and astronomers made many attempts to try and spot them. Unfortunately, it appears to have none. Astronomers will keep looking, of course, but it doesn't seem too likely that it contains planetary neighbors. Barnard's star is located in the direction of the constellation Ophiuchus.

Wolf 359

Wolf 359
Wolf 359 is the reddish-orange star just above the center in this image. Klaus Hohmann, public domain via Wikimedia.

Here's an interesting bit of trivia about this star: it was the location of an epic battle on the television series Star Trek the Next Generation, where the cyborg-human Borg race and the Federation fought for the primacy of the galaxy. Most Trekkies know the name of this star and what it means in the Trekiverse. 

In reality, Wolf 359 is located only 7.78 light-years from Earth. It looks pretty dim to observers. In fact, to be able to see it, they have to use telescopes. It's not visible to the naked eye. That's because Wolf 359 is a faint red dwarf star. It's located in the direction of the constellation Leo.

Lalande 21185

red dwarf star
An artist's concept of a red dwarf star with a possible planet. If Lalande 21185 had a planet, it might look like this. NASA, ESA and G. Bacon (STScI)

Located in the constellation Ursa Major, Lalande 21185 is a faint red dwarf that, like many of the stars in this list, is too dim to be seen with the naked eye. However, that hasn't kept astronomers from studying it. That's because it may well have planets orbiting it. Understanding its planetary system would give more clues to how such worlds form and evolve around older stars. It's named for the 19th-century French astronomer Joseph Jérôme Lefrançois de Lalande. 

As close as it is (at a distance of 8.29 light-years) it is not likely that humans will travel to Lalande 21185 soon. Perhaps not for generations. Still, astronomers will keep checking on possible worlds and their habitability for life.

Sirius

Pictures of the Star Sirius - The Dog Star, Sirius, and its Tiny Companion
Pictures of the Star Sirius - The Dog Star, Sirius, and its Tiny Companion. NASA, H.E. Bond & E. Nelan(STScI); M. Barstow & M. Burleigh(Univ. of Leicester); & J.B. Holberg(UAz)

Nearly everyone knows about Sirius. It's the brightest star in our night-time sky and has been, at times in our history, used as a harbinger of planting by the Egyptians, and a predictor of seasonal change by other civilizations.

Sirius is actually a binary star system containing Sirius A and Sirius B and lies 8.58 light-years from Earth in the constellation Canis Major. Known more commonly as the Dog Star. Sirius B is a white dwarf, the type of object that will be left behind once our Sun reaches the end of its life. 

Luyten 726-8

An x-ray view of Gliese 65, also known as Luyten 726-8. Chandra X-Ray Observatory

Located in the constellation Cetus, this binary star system is 8.73 light-years from Earth. It is also known as Gliese 65 and is a binary star system. One of the members of the system is a flare star and it varies in brightness over time. The star is named for Willem Jacob Luyten who helped determine its proper motion. 

Ross 154

scorp_sag.jpg
A chart of the sky containing Scorpius and Sagittarius. Ross 154 is a faint star in Sagittarius. Carolyn Collins Petersen

At 9.68 light-years from Earth, this red dwarf is well known to astronomers as an active flare star. It regularly increases its surface brightness by an entire order of magnitude in a matter of minutes, then quickly dims down for a short time.

Located in the constellation Sagittarius, it is actually a close neighbor of Barnard's star. The American astronomer Frank Elmore Ross first cataloged it in 1925 as part of his search for variable stars. 

Ross 248

andromeda_perseus_dc.jpg
Ross 248 is a dim star in the constellation Andromeda. Carolyn Collins Petersen

Ross 248 is about 10.3 light-years from Earth in the constellation Andromeda. It was also cataloged by Frank Elmore Ross. The star is actually moving so fast through space that in about 36,000 years it will actually take over the title as the closest star to Earth (besides our Sun) for about 9,000 years. It would be interesting to see it at that time. 

Since Ross 248 is a dim red dwarf, scientists are quite interested in its evolution and eventual demise. The Voyager 2 probe will actually make a close pass within 1.7 light-years of the star in about 40,000 years. However, the probe will most likely be dead and silent as it flies by.

Epsilon Eridani

The star Epsilon Eridani (the yellow star at the right) is thought to have at least two worlds orbiting it. NASA, ESA, G. Baco

Located in the constellation Eridanus, this star lies 10.52 light-years from Earth. It is the closest star to have planets orbiting around it. It also the third closest star that is visible to the naked eye.

Epsilon has a dust disk around it and appears to have a planetary system. Some of those worlds may exist in its habitable zone, a region that allows liquid water to flow freely on planetary surfaces. 

This star also has an intriguing place in science fiction. In Star Trek, it was suggested as the system where Spock's planet, Vulcan, existed. It also played a role in the Babylon 5 series, and has shown up in various movies and TV shows including "The Big Bang Theory."