Information on the Nearest Stars

*Sun - Type=G2,

Magnitude=-26.8, Distance=0.0000158 ly
A typical yellow dwarf star. It has eight planets orbiting it.

*Proxima Centauri - Type=M5,

Magnitude=11.0, Distance=4.22 ly
This dim red dwarf is the nearest star to the Sun, and it is a member of the Alpha Centauri system despite lying 0.24 light years from the main pair of stars, requiring over one million years to orbit them. Proxima was discovered in 1915 by Robert Innes and was at that time the least luminous star known. It is also a flare star - capable of brightening a magnitude or more in minutes.

*Alpha Centauri A,B - Type=G2+K0,

Magnitudes=0.0+1.4, Distance=4.39 ly
Just slightly further from us than Proxima, lie the orange and yellow dwarf stars that make up Alpha Centauri. Orbiting each other in an 80 year period, together they make up one of the brightest objects in southern hemisphere skies. Seen from Alpha Centauri, the third member of the system, Proxima, is a dim (magnitude 4.8) star.

*Barnard's Star - Type=M5,

Magnitude=9.6, Distance=5.94 ly
Famous for having the largest proper motion of any star, this dim red dwarf travels 0.29 degrees against the background sky in a century. Discovered by E Barnard in 1916, it was thought in the 1960's to have a couple of unseen planets orbiting it, but later observations disproved this. In another 8000 years Barnard's Star will become the closest star to us.

*Wolf 359 - Type=M6,

Magnitude=13.5, Distance=7.80 ly
An excessively dim red dwarf discovered by Max Wolf in 1918. For 25 years it was the least luminous star known.

*Lalande 21185 - Type=M2,

Magnitude=7.5, Distance=8.31 ly
Recorded in JJ Lalande's star catalogue compiled in the 1790's, this is one of the brightest red dwarfs in the sky, but it still needs binoculars to see it. G Gatewood reported in 1996 the possible indications of a couple of Jupiter sized planets orbiting it but this remains unconfirmed.

*Sirius A,B - Type=A1+DA,

Magnitudes=-1.4+8.4, Distance=8.60 ly
This brilliant white star is the brightest star in the night sky and the most luminous star within 25 light years. Its white dwarf companion was first seen in 1852, the first white dwarf ever seen. The orbital period is 50 years.

*Luyten 726-8 A,B - Type=M5+M5,

Magnitudes=12.4+13.3, Distance=8.73 ly
This is a dim binary system consisting of two red dwarfs. The system is perhaps more famously known as UV Ceti, the variable-star name of the second star in the system. It is a famous flare star and can visibly brighten by several magnitudes as it ejects flares from its surface similar to the ones seen on the surface of the Sun, but far more energetic. Both stars require about 200 years to orbit each other.

*Ross 154 - Type=M4,

Magnitude=10.4, Distance=9.69 ly
A dim red dwarf. It is one of a number of nearby stars catalogued by Frank Ross in the 1930's. It is also a known flare star.

*Ross 248 - Type=M6,

Magnitude=12.3, Distance=10.33 ly
Another dim red dwarf.

Epsilon Eridani - Type=K2,

Magnitude=3.7, Distance=10.50 ly
An orange dwarf star. This star was searched for signs of intelligent life with the Green Bank radio telescope in 1960. The results, predictably, were negative. The IRAS satellite detected a lot of dust orbiting this star indicating a possible forming solar system, and even more recently, (Aug 2000), a Jupiter sized planet has been detected orbiting this star at a distance of 3.2 AU (480 million km).

*Lacaille 9352 - Type=M2,

Magnitude=7.4, Distance=10.73 ly
A fairly bright red dwarf which can easily be seen with binoculars, it was first recorded in Nicolas de Lacaille's catalogue of southern hemisphere stars compiled around 1752.

*Ross 128 - Type=M4,

Magnitude=11.1, Distance=10.89 ly
A dim red dwarf, also known as FI Vir - its variable star designation.

*Luyten 789-6 A,B,C - Type=M5+M5+M7,

Magnitudes=13.3+13.3+14.0, Distance=11.1 ly
There seems to be three red dwarfs in this system. The main pair orbiting each other in a 2 year period, and a dim third star orbiting the first at a very close range.

*Procyon A,B - Type=F5+DA,

Magnitudes=0.4+10.7, Distance=11.41 ly
A brilliant yellow-white star, and the eighth brightest star in the sky. With twice the diameter of the Sun, Procyon is also the largest star within 25 light years. Procyon is orbited by a white dwarf companion first seen optically in 1896. The orbital period is 41 years.

*61 Cygni A,B - Type=K5+K7,

Magnitudes=5.2+6.1, Distance=11.41 ly
This binary system of two orange dwarf stars is famous for being the first star ever to have its distance measured by F Bessel in 1838. Both stars are very similar but are widely separated (86 AU) requiring about 700 years to orbit each other.

*Struve 2398 A,B - Type=M4+M5,

Magnitudes=8.9+9.7, Distance=11.6 ly
A binary system of two red dwarfs named Struve 2398 from a catalogue of double stars published in 1827. This system is also known by the rather more boring name of BD+59°1915. The two stars are quite widely separated (50 AU) and orbit each other in a 450 year period.

*Groombridge 34 A,B - Type=M2+M6,

Magnitudes=8.1+11.1, Distance=11.64 ly
Another pair of red dwarfs, this system is usually called Groombridge 34 from an 1838 catalogue of northern stars or sometimes BD+43°44. Both stars are variable in brightness and have the variable star names of GX And and GQ And. Both stars lie far apart from each other (150 AU) and orbit each other in a 2500 year period.

*Giclas 51-15 - Type=M6,

Magnitude=14.8, Distance=11.8 ly
This excessively dim red dwarf is the least luminous star within 14 light years. It shines with just 0.01% of the Sun's luminosity.

*Epsilon Indi A,B,C - Type=K5+T1+T6,

Magnitude=4.7, Distance=11.83 ly
An orange dwarf. It is a similar star to Epsilon Eridani, although a little bit smaller and dimmer. Epsilon Indi is orbited by a pair of brown dwarfs - failed stars that are too small to burn. They were discovered in 2003 and they orbit each other in a 16 year period, and they are 1500 AU (220 billion km) from the main star and they require about 70 000 years to orbit it.

*Tau Ceti - Type=G8,

Magnitude=3.5, Distance=11.90 ly
The nearest, single, sun-like star. It was searched (unsuccessfully) for any signs of intelligent life in 1960, along with Epsilon Eridani.

*Luyten 372-58 - Type=M5,

Magnitude=13.0, Distance=12.1 ly
A very dim red dwarf. Although this star was catalogued decades ago, it has only recently had its distance determined with any accuracy.

*Luyten 725-32 - Type=M5,

Magnitude=12.1, Distance=12.1 ly
Another dim red dwarf.

*Luyten's Star - Type=M3,

Magnitude=9.8, Distance=12.39 ly
A red dwarf. It is named after Willem
who realised it was a nearby star in 1935. The star lies just 1.2 light years away from Procyon, but it is not associated with it.

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