Alpha Centauri is not a single star but a multiple star system.
The two main stars are Alpha Centauri A and Alpha Centauri B. These orbit each other fairly closely (closely enough that despite them being only a little over four-light years from Earth, they appear as a single star to the naked eye).
Considerably further away from the two (but still close, by astronomical standards) is the star known as Proxima Centauri. It's believed to be gravitationally associated with (i.e. orbiting) the AB pair and is also known as Alpha Centauri C. Proxima is far enough from AB that, if it were bright enough to be seen with the naked eye, it would appear as a distinct star (in fact, it's a couple of degrees from AB; about four times the width of the full Moon).
Because of its orbit (if it's in orbit, which we don't actually know for sure ... it might just happen by coincidence to be passing close by), Proxima is currently nearer to us than A and B are, hence the name.
Proxima Cenatauri is the closest star to Earth (after the Sun of course). It is a red dwarf star about 4.2 light-years (3.97 × 1013 km) away.
http://en.wikipedia.org/wiki/Proxima_Centaurus
The Milky Way Galaxy.
When Mars is lined up along our line of sight toward Proxima Centauri, it's about 0.00018 percent closer to it than we are. And when it's on the other side of the sun, on the extended line of sight from Proxima Centauri through the Earth, it's about 0.00093 percent farther from it than we are. Any measurement of the position or motion of Proxima Centauri, or any other star outside the solar system, that's made from Mars, or any other solar system planet, is indistinguishable from the same measurement made from Earth. HOWEVER .... because Mars has a bigger "baseline" than the Earth (due to a wider orbit), the parallax angle would be correspondingly larger.
The Sun is "really" the closest star at 150,000,000 km (93,000,000 miles)Proxima Centauri is the closest star to us, at a distance of approximately 4.2 light years.(Proxima is Latin for "next to" or "nearest to")Alpha Centauri is the closest star system to us at a distance of approximately 4.3 light yearsThe Centauri system is a triple star system Centauri A and B have a mean separation of 11 AU's and are similar in size and temp to the Sun.Centauri C is a red dwarf it can not be seen with the unaided eye and was not discovered until 1918See related link for more information.
Alpha Centauri - the star system in the constellation Centaurus, the nearest to the Sun. It consists of three components: a close binary system α Centauri A and α Centauri B and invisible to the naked eye, the red dwarf Proxima Centauri (the last star is usually treated separately.) Stars have their own names Rigel Kentavrus ("Centaur's foot"), Bungula ("hoof") and Tolimán, but they are used rarely. This system is located at a distance of 4, 4 light-years or 41,627,214,079,352 kilometers.
Alpha Centauri, although it appears to the naked eye as a single star, is a binary pair. Together they are designated Alpha Centauri AB, the more massive and luminous in the pair designated Alpha Centauri A, the less massive and luminous Alpha Centauri B. Together, this pair is the third brightest "star" in the night sky. There is a third star probably interacting gravitationally with the pair, Proxima Centauri, also designated Alpha Centauri C, a red dwarf which is not visible to the naked eye but is the next closest star to our Sun. Alpha Centauri B has about 90% of the mass of our Sun and is about 45% as bright. Note that Alpha Centauri B is not the "second" star (second brightest) in the constellation Centaurus: that is Beta Centauri, which is itself a trinary star system.
Actually the nearest star (except for the sun) is Proxima Centauri is next at 4.3 light-years from the Earth. It would take 3.4 years at one light-year/year for radio waves to reach Earth from there. This is because the radio waves are travelling in a vacuum and all electromagnetic wave in a vacuum travel at "C" AKA the speed of light.
As the closest star to our sun, Proxima Centauri is in our galaxy.
Proxima Centauri.
It is the nearest star to our solar system an in the same galaxy as us, the Milky Way.
Proxima Centauri is in the constellation Centaurus.
Proxima Centauri has a temperature of about 3,042K
Proxima Centauri _IS_ a sun.
No. Proxima Centauri is a red dwarf.
Proxima Centauri is a star. It has no life forms.
No, Proxima Centauri and Alpha Centauri do not revolve around each other.
As of June 2014, the closest known star to the Sun is Proxima Centauri. Proxima Centauri is located 4.24 light-years away from the Sun.
Proxima Centauri - album - was created on 2001-10-15.
1 / as = 1.3003901170351105331599479843953 Distance to Proxima Centauri from wikipedia is 1.3009 ± 0.0005 PC