Barnard's Star
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Lying at a distance of about 1.8 pc or 5.96 ly, Barnard's star is the fifth closest known star to Earth. Only the Sun and the three components of the Alpha Centauri system are closer. But Barnard's star is a red dwarf (spectral type M4), so despite its proximity it is too faint to see without a telescope or powerful binoculars. Its apparent magnitude is 9.57. Although Barnard's star was long thought to be a quiescent, old star, astronomers recently reported a flare that was observed in 1998 (but not regarded as important by the planet-seeking astronomer who observed it), making it a surprising flare star[Astronomy.com: A Flare for Barnard's Star]. It has the variable star designation V2500 Ophiuchi.
The proper motion at this distance corresponds to a relative lateral speed of 90 kilometres per second (km/s), and its redshift indicates its radial velocity (towards the Sun) is 106.8 km/s (from SIMBAD). In fact, Barnard's Star is approaching the Sun so rapidly that it will be the nearest star to the Sun around AD 11,800, reaching as close as 3.8 light-years.[link]
Barnard's Star's closest neighbour is currently Ross 154, at 1.66 pc or 5.41 ly away.
Supposed planets
For many years from 1963 onwards, a substantial number of astronomers accepted a claim by Peter van de Kamp that he had detected a perturbation in the proper motion of Barnard's star consistent with its having one or more planets comparable in mass with Jupiter. When independent data were collected in the 1980s, this conclusion came to be disputed and the consensus is now that van de Kamp's claim was erroneous. During the period that the claim was accorded credibility, it contributed to the star's fame among the science fiction community and the star's adoption as a target for Project Daedalus (The British Interplanetary Society's proposal for an interstellar space probe).Barnard's Star in fiction
In Douglas Adams's The Hitchhiker's Guide to the Galaxy, Barnard's Star is a way station for interstellar travellers.
In Michael Moorcock's The Black Corridor, Barnard's Star is the destination for a group of people fleeing from social breakdown on Earth.
In David Braben's computer game Frontier, Barnard's Star is an important Federation industrial system with heavy mining and refining industry close to Earth and the other Core Systems. It proved to be the ideal beginners trading place - no pirates and high profits, exporting robots or computers to Sol and importing Luxury Goods from there could make you a millionaire in no time at all.
See also
References
- E. E. Barnard, A small star with large proper motion, [Astronomical Journal 29 (1916) 181–183] (1916AJ.....29..181B)
External links
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