Barnard's Star^[1]

Barnard's Star
Observation data Epoch J2000
Constellation	Ophiuchus
Right ascension	17h 57m 48.5s
Declination	+04° 41' 36"
Apparent magnitude (V)	9.57
Characteristics
Spectral type	M4 V
B-V color index	1.74
U-B color index	1.28
Variable type	BY Draconis
Astrometry
Radial velocity (Rv)	-110.8 km/s
Proper motion (μ)	RA: -797.84 mas/yr Dec.: 10326.93 mas/yr
Parallax (π)	546.98 ± 1.00 mas
Distance	5.96 ± 0.01 ly (1.828 ± 0.003 pc)
Absolute magnitude (MV)	13.26
Details
Mass	0.17 M☉
Radius	0.15-0.20 R☉
Luminosity	0.0004 L☉
Temperature	3,134 K
Metallicity	10-32% Sun
Rotation	130.4 days
Age	~1.0 × 1010 years
Other designations
Velox Barnardi, V2500 Oph, BD+04°3561a, GCTP 4098.00, GJ 699, LHS 57, Munich 15040, Gl 140-024, LTT 15309, LFT 1385, Vyssotsky 799, and HIP 87937.
Database references
SIMBAD	Oph data
ARICNS	data

Barnard's Star is a very low-mass star in the constellation Ophiuchus which was discovered by the astronomer E. E. Barnard in 1916. Barnard measured its proper motion to 10.3 arcseconds per year, which remains the largest known proper motion of any star relative to the Sun.^[2] Lying at a distance of about 1.8 parsecs or 5.96 light-years, Barnard's Star is the nearest star in the constellation Ophiuchus and is also the second closest known star system to the Sun and the fourth closest known individual star after the three components of the Alpha Centauri system. Image File history File linksMetadata Barnardstar2006. ... In astronomy, an epoch is a moment in time for which celestial coordinates or orbital elements are specified. ... This article or section does not cite its references or sources. ... Ophiuchus is one of the 88 constellations, and was also one of the 48 listed by Ptolemy. ... Equatorial Coordinates Right ascension (abbrev. ... In astronomy, declination (dec) is one of the two coordinates of the equatorial coordinate system, the other being either right ascension or hour angle. ... // Headline text HEY!! HOW ARE YOU ALL?? Its nice of you to come read this page. ... In astronomy, stellar classification is a classification of stars based initially on photospheric temperature and its associated spectral characteristics, and subsequently refined in terms of other characteristics. ... In astronomy, color index is a simple numerical expression that determines the color of an object, which in the case of a star gives its temperature. ... In astronomy, color index is a simple numerical expression that determines the color of an object, which in the case of a star gives its temperature. ... Most stars are of almost constant luminosity. ... BY Draconis variables are main sequence variable stars of late spectral types, usually K or M. They exhibit variations in their luminosity due to rotation of the star coupled with star spots, and other chromospheric activity. ... This article does not cite its references or sources. ... Radial velocity is the velocity of an object in the direction of the line of sight. ... kilometre per second is an SI derived unit of both speed (scalar) and velocity (vector), signified by the symbol km/s or km s-1. ... The proper motion of a star is the motion of the position of the star in the sky (the change in direction in which we see it, as opposed to the radial velocity) after eliminating the improper motions of the stars, which affect their measured coordinates but are not real... A milliarcsecond (m, mas) , or a thoundsanth of an arcsecond. ... A year is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ... A milliarcsecond (m, mas) , or a thoundsanth of an arcsecond. ... A year is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ... This article or section does not cite its references or sources. ... A milliarcsecond (m, mas) , or a thoundsanth of an arcsecond. ... Distance is a numerical description of how far apart things lie. ... A light-year or lightyear, symbol ly, is the distance light travels in vacuum in one Julian year. ... Stellar parallax motion The parsec (symbol pc) is a unit of length used in astronomy. ... In astronomy, absolute magnitude is the apparent magnitude, m, an object would have if it were at a standard luminosity distance away from us (in the absence of interstellar extinction!). It allows the overall brightnesses of objects to be compared without regard to distance. ... Unsolved problems in physics: What causes anything to have mass? Mass is a property of a physical object that quantifies the amount of matter and energy it is equivalent to. ... In astronomy, the solar mass is a unit of mass used to express the mass of stars and larger objects such as galaxies. ... In classical geometry, a radius of a circle or sphere is any line segment from its center to its boundary. ... In astronomy, the solar radius is a unit of length used to express the size of stars and larger objects such as galaxies. ... Luminosity has different meanings in several different fields of science. ... The solar luminosity, , is a unit of luminosity (power emitted in the form of photons) conventionally used by astronomers to give the luminosities of stars. ... Fig. ... The Kelvin scale is a thermodynamic (absolute) temperature scale where absolute zero—the lowest possible temperature where nothing could be colder and no heat energy remains in a substance—is defined as zero kelvin (0 K). ... In astronomy, the metallicity of an object is the proportion of its matter made up of chemical elements other than hydrogen and helium. ... A sphere rotating around its axis. ... The Pleiades, an open cluster of stars in the constellation of Taurus. ... A year is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ... In astronomy, many stars are referred to simply by catalogue numbers. ... In astronomy, many stars are referred to simply by catalogue numbers. ... In astronomy, many stars are referred to simply by catalogue numbers. ... In astronomy, many stars are referred to simply by catalogue numbers. ... In astronomy, many stars are referred to simply by catalogue numbers. ... Henry Lee Giclas (born December 9, 1910) is an American astronomer. ... Alexander N. Vyssotsky (born May 23, 1888 in Moscow, Russia; died December 31, 1973 in Winter Park, Florida) was an astronomer. ... In astronomy, many stars are referred to simply by catalogue numbers. ... SIMBAD (the Set of Identifications, Measurements, and Bibliography for Astronomical Data) is a database of astronomical information about objects within the Milky Way. ... The Pleiades, an open cluster of stars in the constellation of Taurus. ... This article or section does not cite its references or sources. ... Ophiuchus is one of the 88 constellations, and was also one of the 48 listed by Ptolemy. ... An astronomer or astrophysicist is a person whose area of interest is astronomy or astrophysics. ... Edward Emerson Barnard (December 16, 1857 – February 6, 1923) was an American astronomer. ... 1916 (MCMXVI) was a leap year starting on Saturday (link will take you to calendar). ... The proper motion of a star is the motion of the position of the star in the sky (the change in direction in which we see it, as opposed to the radial velocity) after eliminating the improper motions of the stars, which affect their measured coordinates but are not real... A second of arc or arcsecond is a unit of angular measurement which comprises one-sixtieth of an arcminute, or 1/3600 of a degree of arc or 1/1296000 ≈ 7. ... The Sun is the star of our solar system. ... This article is about the unit of length. ... Light Years is also the American name of the Rene Laloux animated film Gandahar. ... A star system or stellar system is a system comprised of a star or group of stars, and, perhaps, planetary systems of smaller bodies (such as planets or asteroids), in gravitational association. ... The Sun is the star of our solar system. ... This list of the nearest stars to Earth is ordered by increasing distance out to a maximum of 5 parsecs (16. ... Alpha Centauri (α Cen / α Centauri) is the brightest star system (a triple star system) in the southern constellation of Centaurus, and contains the fourth brightest star in the night sky, with an apparent visual magnitude of −0. ...

Barnard's Star is a relatively well-studied astronomical object, and has likely received more attention than any other M dwarf star given its proximity and favourable location for observation near the celestial equator.^[3] It has also been the subject of some controversy. For a decade from the early 1960s onward, an erroneous discovery of a planet or planets in orbit around Barnard's star was accepted by astronomers. The star is notable as the target for a study on the possibility of rapid, unmanned travel to nearby star systems. Research has focused on stellar characteristics, astrometry, and refining the limits of possible planets. According to the Hertzsprung-Russell diagram, a red dwarf star is a small and relatively cool star, of the main sequence, either late K or M spectral type. ... The celestial equator is a great circle on the imaginary celestial sphere, which could be constructed by inflating the Earths equator until it intersects with said sphere. ... The eight planets and three dwarf planets of the Solar System. ... This article does not cite its references or sources. ...

System summary

Barnard's Star is a red dwarf of the faint M4 spectral type and so, despite its proximity, it is too faint to see without a telescope. Its apparent magnitude is 9.57. This compares to -1.5 for Sirius (the brightest Star in the night sky) and 6 for the faintest visible objects; the scale is logarithmic and 9.57 is nowhere near the visible range. Red Dwarf is a British science fiction sitcom that ran for eight series, from 1988 to 1999. ... In astronomy, stellar classification is a classification of stars based initially on photospheric temperature and its associated spectral characteristics, and subsequenly refined in terms of other characteristics. ... 50 cm refracting telescope at Nice Observatory. ... // Headline text HEY!! HOW ARE YOU ALL?? Its nice of you to come read this page. ... Sirius (α CMa / α Canis Majoris / Alpha Canis Majoris) is the brightest star in the night-time sky, with a visual apparent magnitude of −1. ... A logarithmic scale is a scale of measurement that uses the logarithm of a physical quantity instead of the quantity itself. ...

A very old star at 11 to 12 billion years, Barnard's Star has lost a great deal of rotational energy and periodic changes in its light indicate it rotates just once every 130 days (compared to just over 25 days for the Sun).^[4] Given its age, Barnard's Star was long assumed to be quiescent in terms stellar activity. However, in 1998 astronomers observed an intense solar flare, making it a surprising flare star.^[5] It has the variable star designation V2500 Ophiuchi. A Solar Flare and CME, courtesy NASA A solar flare is a violent explosion in the Suns atmosphere with an energy equivalent to a billion megaton nuclear bombs, traveling at about 1 million km per hour. ... A flare star is a variable star which can undergo unpredictable dramatic increases in brightness for a few minutes or a few hours. ... Most stars are of almost constant luminosity. ...

The proper motion of the body corresponds to a relative lateral speed ("sideways" relative to the Sun) of 90 kilometres per second (km/s). The 10.3 seconds of arc covered annually amounts to a quarter of a degree in a human lifetime, roughly the angular diameter of the full Moon.^[6] To help compare different orders of magnitude, the following list describes various speed levels between 1. ... kilometre per second is an SI derived unit of both speed (scalar) and velocity (vector), signified by the symbol km/s or km s-1. ...

Its radial velocity towards the Sun can be measured by its redshift. Two measurements are given in catalogues: 106.8 km/s in SIMBAD, and 110.8 km/s in ARICNS and elsewhere. These measurements, combined with proper motion, suggest a true velocity relative to the Sun of 139.7 and 142.7 km/s, respectively.^[7] In fact, Barnard's Star is approaching the Sun so rapidly that it will be the nearest star around AD 11,800, at a distance of 3.8 light-years.^[8] Redshift of spectral lines in the optical spectrum of a supercluster of distant galaxies (right), as compared with that of the Sun (left). ... In astronomy, many stars are referred to simply by catalogue numbers. ... SIMBAD (the Set of Identifications, Measurements, and Bibliography for Astronomical Data) is a database of astronomical information about objects within the Milky Way. ...

Barnard's Star, all positions since 1985.

Barnard's Star is 17% of a solar mass and has a radius 15-20% that of the Sun.^[9] Its effective temperature is 3134(+/-102)K and it has a visual luminosity just 4/10000 of solar luminosity, corresponding to a bolometric or absolute luminosity of 34.6/10000.^[3] It is so faint that, were it to replace the Sun, it would only appear 100 times brighter than a full moon and the Earth's oceans would freeze out.^[9] Image File history File links Barnard2005. ... Image File history File links Barnard2005. ... In astronomy, the solar mass is a unit of mass used to express the mass of stars and larger objects such as galaxies. ... The Sun is the star of our solar system. ... The effective temperature of a star is the temperature of its visible surface, as opposed to the core at which it generates its energy through thermonuclear reactions or the rarefied corona of great heat where electrons meet ionized gases with the radiation of heat but in so sparse a gas... Look up K, k in Wiktionary, the free dictionary. ...

Barnard's Star's closest neighbour is currently Ross 154, at 1.66 pc or 5.41 ly away. With the exception of the Sun and Alpha Centauri A and B, all of Barnard's star's neighbours within 10 ly are other faint K or M spectral class red dwarfs.^[9] Ross 154 is a red dwarf star approximately 3. ...

Supposed planets

For a decade 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.^[8] Van de Kamp had been observing the star from 1938, attempting, with colleagues at the Swarthmore College observatory, to find extremely minute variations of 1 micrometre in its position on photographic plates consistent with "wobbles" in the star that would indicate a planetary companion; this involved as many as ten people averaging their results in looking at plates, to avoid systemic, individual errors.^[10] Van de Kamps's initial suggestion was a 1.6 Jupiter mass planet at 4.4 AUs in a slightly eccentric orbit, these measurements apparently refined in a 1969 paper. Later that same year he would suggest two planets of 1.1 and 0.8 Jupiter masses.^[11] 1963 (MCMLXIII) was a common year starting on Tuesday (the link is to a full 1963 calendar). ... Piet van de Kamp (December 26, 1901 – May 18, 1995), known as Peter van de Kamp in the United States, was a Dutch-American astronomer. ... Atmospheric characteristics Atmospheric pressure 70 kPa Hydrogen ~86% Helium ~14% Methane 0. ... 1938 (MCMXXXVIII) was a common year starting on Saturday (link will take you to calendar). ... Swarthmore College is a private liberal arts college in the United States with an enrollment of about 1450 students. ... A micrometre (American spelling: micrometer, symbol µm) is an SI unit of length equal to one millionth of a metre, or about a tenth of the size of a droplet of mist or fog. ... Photographic plates were one of the earliest forms of photographic film, in which a light-sensitive emulsion of silver salts was applied to a glass plate. ... In astrodynamics orbital perturbation is an effect on an objects orbit due to the range of external influences. ...

Artist's conception of a planet in orbit around a red dwarf

Other astronomers attempted to duplicate Van de Kamp's finding and two important papers in 1973 undermined the claim of a planet or planets. Gatewood and Einrich, at a different observatory and using newer plate measuring techniques, failed to verify the planetary companion.^[12] Another paper published by Hershey four months earlier, also using the Swarthmore observatory, suggested a cause for the discrepancy. He found that changes in the astrometric field of various stars correlated to the timing of adjustments and modifications that had been done on the telescopic lens;^[13] the planetary "discovery" was an artifact of maintenance and upgrade work. Image File history File links RedDwarfPlanet. ... Image File history File links RedDwarfPlanet. ...

Van de Kamp refused to acknowledge any error for the rest of his life, publishing a supposed confirmation of two planets as late as 1982.^[14] In general a gregarious and well-admired man, he may have felt betrayed by colleagues who disputed his findings. Wulff Heintz, van de Kamp's successor at Swarthmore and an expert on double stars, questioned his findings and began publishing criticisms from 1976 onwards; the two are reported to have become estranged because of this.^[15] This page is about a novel by Robert Heinlein. ...

While not completely ruling out the possibility of planets, null results for planetary companions continued throughout the 1980s and 90s, the latest based on interferometric work with Hubble space telescope in 1999.^[16] Interferometry is the applied science of combining two or more input points of a particular data type, such as optical measurements, to form a greater picture based on the combination of the two sources. ... The Hubble Space Telescope (HST) is a telescope in orbit around the Earth, named after astronomer Edwin Hubble for his discovery of galaxies outside the Milky Way and his creation of Hubbles Law, which calculates the rate at which the universe is expanding. ...

While the controversy may have dampened work on extrasolar planets, it did have a salutatory effect on the profile of Barnard's Star. 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. Science fiction is a form of speculative fiction principally dealing with the impact of imagined science and technology, or both, upon society and persons as individuals. ... An artists conception of the British Interplanetary Society design for Project Daedalus Project Daedalus was a study conducted between 1973 and 1978 by the British Interplanetary Society to design a plausible interstellar unmanned spacecraft. ...

Project Daedalus

Main article: Project Daedalus

Excepting the planet controversy, the best known work related to Barnard Star's is Project Daedalus. Undertaken between 1973 and 1978, it suggested that rapid, unmanned travel to another star system is possible with existing or near-future technology.^[17] Barnard's Star was chosen as a target in part because of the assumption of planetary companions.^[18] An artists conception of the British Interplanetary Society design for Project Daedalus Project Daedalus was a study conducted between 1973 and 1978 by the British Interplanetary Society to design a plausible interstellar unmanned spacecraft. ... An artists conception of the British Interplanetary Society design for Project Daedalus Project Daedalus was a study conducted between 1973 and 1978 by the British Interplanetary Society to design a plausible interstellar unmanned spacecraft. ...

The theoretical model suggested that a nuclear pulse rocket employing nuclear fusion (specifically, electron bombardment of deuterium and helium-3) could achieve a velocity of 12% light speed over a four-year acceleration phase. The star could then be reached in 50 years, i.e. within a human lifetime.^[18] Along with detailed investigation of the star and any companions, the interstellar medium would be examined and baseline astrometric readings performed.^[17] The deuterium-tritium (D-T) fusion reaction is considered the most promising for producing fusion power. ... Deuterium, also called heavy hydrogen, is a stable isotope of hydrogen with a natural abundance in the oceans of one atom in 6400 of hydrogen (see VSMOW; the abundance changes slightly from one kind of natural water to another). ... Helium-3 is a non-radioactive and light isotope of helium. ... Cherenkov effect in a swimming pool nuclear reactor. ... The distribution of ionized hydrogen (known by astronomers as H II (aitch two) from old spectroscopic terminology) in the parts of the Galactic interstellar medium visible from the Earths northern hemisphere (from the Wisconsin H-Alpha Mapper Survey) In astronomy, the interstellar medium (or ISM) is the matter (interstellar...

The initial Project Daedalus model would spark further theoretical research. In 1980, Freitas suggested a more ambitious plan: a self-reproducing interstellar probe intended to search for and make contact with extraterrestrial life. Built and launched in Jovian orbit, it would reach Barnard's Star in 47 years under much the same parameters as the original Project Daedalus. Once at the star, however, it would begin self-automated replication activities. A factory would be constructed, initially to manufacture exploratory probes and eventually to create a copy of the original spacecraft after 1000 years.^[19] A von Neumann probe is a specific example of a hypothetical concept based on the work of Hungarian-born American mathematician and physicist John von Neumann. ... The Arecibo Observatory in Puerto Rico, currently used by the SETI project in the search for extraterrestrial life Extraterrestrial life is life that may exist and originate outside the planet Earth, the only place in the universe currently known by humans to support life. ... From top: Neptune, Uranus, Saturn, and Jupiter. ...

Research

Barnard's Star has a diameter only 15 to 20% that of the Sun.^[20]

While the research following from van de Kamp and focused on the planetary search has perhaps had the highest profile, Barnard's star is a well-documented object in other respects. Image File history File linksMetadata Barnard'sStarSize. ... Image File history File linksMetadata Barnard'sStarSize. ...

Stellar characteristics and astrometry

Several papers on mass-luminosity relations appeared prior to Dawson's definitive work in 2003. Along with refining the temperature and luminosity (see above), this paper suggested that previous estimates of Barnard's Star radius consistently underestimated the value; it suggests 0.20 solar radius (+/-0.008 solar radius), at the high end of the range typically provided.^[3] In astronomy, the solar radius is a unit of length used to express the size of stars and larger objects such as galaxies. ...

In a broad survey of the metallicity of M dwarf stars, Barnard's Star's was placed between -0.05 and -0.1 on the metallicity scale, or roughly 10 to 32% as metal-enriched as the Sun.^[20] Metallicity, the proportion of stellar mass made up of elements heavier than helium, helps classify stars relative to the galactic population. Barnard's Star seems typical of the old, red dwarf population II stars, yet these are also generally metal-poor halo stars. While sub-solar, Barnard's Star's metallicity is actually higher than a halo star and is in keeping with the low end of the metal-rich disk star range; this, plus its high space motion, have led to the designation "Intermediate Population II star", between a halo and disk star.^[20][21] In astronomy, the metallicity of an object is the proportion of its matter made up of chemical elements other than hydrogen and helium. ... General Name, Symbol, Number helium, He, 2 Chemical series noble gases Group, Period, Block 18, 1, s Appearance colorless Atomic mass 4. ... Metal-poor is a term that is used to describe the chemical make up of an astronomical object. ... The galactic halo is a region of space surrounding spiral galaxies, including our galaxy, the Milky Way. ... ĐÁA disc is a component of disc galaxies, such as spiral galaxies, or lenticular galaxies. ...

The Hubble telescope work by Benedict and colleagues has been wide-ranging. In 1999 absolute parallax values and absolute magnitude values were refined.^[16] This aided in refining planetary boundaries (see below). Another important paper, by Kurster et al., appeared in 2003. It showed the first detection of a change in the radial velocity of a star caused by its space motion; further variability in radial velocity was attributed to stellar activity.^[21] The Hubble Space Telescope (HST) is a telescope orbiting the Earth at the outer edges of the atmosphere. ... Radial velocity is the velocity of an object in the direction of the line of sight. ...

Refining planetary boundaries

Barnard's Star in NASA's digital star survey.

Work on astrometry and other characteristics may also yield further information on the possibility of planets. By refining the values of a star's motion, the mass and orbital boundaries for possible planets are reduced. More simply, astronomers are often able to describe what types of planets cannot orbit a star. M dwarfs such as Barnard's Star are more easily studied than larger stars in this regard because their lower mass renders perturbations more obvious.^[22] In this way, Gatewood was able to show in 1995 that planets of 10 Jupiter mass (the lower limit for brown dwarfs) were impossible around Barnard's star,^[8] in a paper which helped refine the task of providing negative certainty regarding planetary objects in general.^[23] The 1999 work with Hubble would further exclude planetary companions 0.8 Jupiter masses with an orbital period of less than 1000 days,^[16] while Kurtzer would determine in 2003 that within the habitable zone around Barnard's Star, planets are not possible with an "Msin i" value^[24] of 7.5 Earth masses and 3.1 Neptune masses in general (well below van de Kamp's smallest suggestions).^[21] Image File history File links BarnardsStar. ... Image File history File links BarnardsStar. ... Brown dwarfs are sub-stellar objects (~13 to 75 Jupiter masses) that never fuse hydrogen into helium in their cores, as do stars on the main sequence. ... In astronomy a habitable zone (HZ) is a region of space where conditions are favorable for the creation of life. ...

While this research has greatly restricted the parameters of possible planets around Barnard's Star, it has not ruled them out completely; terrestrial planets are still a possibility but would be difficult to detect. NASA's Space Interferometry Mission and the ESA's Darwin, both scheduled to begin looking for extrasolar Earth-like planets around 2015, have chosen Barnard's Star as a search target.^[9] A terrestrial planet or telluric planet is a planet which is primarily composed of silicate rocks. ... NASA Insignia Listen to this article · (info) This audio file was created from an article revision dated 2005-09-01, and does not reflect subsequent edits to the article. ... The Space Interferometry Mission (SIM), is a NASA mission scheduled for launch in 2010, which will make astrometric observations to determine the positions and distances of stars several hundred times more accurately than any previous program. ... This article is about the European Space Agency. ... Darwin is a proposed European Space Agency (ESA) mission designed to directly detect Earth-like planets orbiting nearby stars, and search for evidence of life on these planets. ... 2015 (MMXV) will be a common year starting on Thursday of the Gregorian calendar. ...

1998 flare

The observation of a solar flare on Barnard's Star has added another element of interest to its study. Noted by Cochran based on changes in the spectral emissions on July 17, 1998 (during an unrelated search for planetary "wobbles"), it took four more years before the flare would be properly analyzed. At that point Paulson, now of Goddard Space Flight Center, suggested that the flare's temperature was 8000K, more than twice normal for the star, although simply analyzing spectra cannot precisely determine the total output of the flare.^[25] Given the essentially random nature of flares, she noted "the star would be fantastic for amateurs to observe."^[5] A Solar Flare and CME, courtesy NASA A solar flare is a violent explosion in the Suns atmosphere with an energy equivalent to a billion megaton nuclear bombs, traveling at about 1 million km per hour. ... A materials emission spectrum is the amount of electromagnetic radiation of each frequency it emits when it is heated (or more generally when it is excited). ... July 17 is the 198th day (199th in leap years) of the year in the Gregorian calendar, with 167 days remaining. ... 1998 (MCMXCVIII) was a common year starting on Thursday of the Gregorian calendar, and was designated the International Year of the Ocean. ... Aerial view of Goddard Space Flight Center. ...

The flare was surprising because intense stellar activity is not expected around stars of such age. Flares, though not completely understood, are believed to be caused by strong magnetic fields, which suppress plasma convection leading to sudden outbursts; strong magnetic fields require a rapidly rotating star, while old stars tend to rotate slowly. An event of such magnitude around Barnard's Star is thus presumed to be rare.^[25] Research on its periodicity, or changes in stellar activity over a given timsescale, also suggest it ought to be quiescent; 1998 research showed weak evidence for periodic variation in Barnard's Star's brightness, noting only one possible starspot over 130 days.^[26] The name Magnetic Fields has been used by: A 1981 album by Jean Michel Jarre; see Magnetic Fields (album) (Les Chants Magnetiques) A computer game developer; see Magnetic Fields (computer game developer) The Magnetic Fields, a band led by Stephin Merritt For magnetic fields in general, see magnetic field. ... A Plasma lamp, illustrating some of the more complex phenomena of a plasma, including filamentation A solar coronal mass ejection blasts plasma throughout the solar system. ... Convection is the internal movement of currents within fluids (i. ... Periodicity is the quality of occurring at regular intervals (e. ...

Barnard's Star in fiction

The attention to which astromers have paid to Barnard's Star, and the speculation as to whether it could support life on an orbiting planet, formed the basis for Will Eisner's 1978 science fiction graphic novel, LIfe On Another Planet, which depicted the reaction of humanity to the news that an extraterrestrial radio signal had been detected from a planet orbiting the star. William Erwin Eisner (March 6, 1917 – January 3, 2005) was an acclaimed American comics writer, artist and entrepreneur. ... Science fiction is a form of speculative fiction principally dealing with the impact of imagined science and technology, or both, upon society and persons as individuals. ... Sabre (1978), one of the first graphic novels. ...

See also

• List of nearest stars
• List of stars named after people
• Barnard's star in fiction

This list of the nearest stars to Earth is ordered by increasing distance out to a maximum of 5 parsecs (16. ... Over the past few centuries, a small number of stars have been named for individuals. ... The planetary systems of stars other than the Sun and its Solar System are a staple element in much science fiction. ...

Notes and references

Edward Emerson Barnard (December 16, 1857 – February 6, 1923) was an American astronomer. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 10 is the 222nd day of the year (223rd in leap years) in the Gregorian Calendar. ... A digital object identifier (or DOI) is a permanent identifier (permalink) given to a World Wide Web file or other Internet document so that if its Internet address changes, users will be redirected to its new address. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 16 is the 228th day of the year (229th in leap years) in the Gregorian Calendar. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 15 is the 227th day of the year in the Gregorian Calendar (228th in leap years), with 138 days remaining. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 10 is the 222nd day of the year (223rd in leap years) in the Gregorian Calendar. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... September 7 is the 250th day of the year (251st in leap years). ... The Milky Way (a translation of the Latin Via Lactea, in turn derived from the Greek Γαλαξίας (Galaxias), sometimes referred to simply as the Galaxy), is a barred spiral galaxy of the Local Group. ... Wolf 424 is a binary star system comprising two red dwarf stars at a distance of approximately 14. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 10 is the 222nd day of the year (223rd in leap years) in the Gregorian Calendar. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 10 is the 222nd day of the year (223rd in leap years) in the Gregorian Calendar. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 9 is the 221st day of the year in the Gregorian Calendar (222nd in leap years), with 144 days remaining. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 10 is the 222nd day of the year (223rd in leap years) in the Gregorian Calendar. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 9 is the 221st day of the year in the Gregorian Calendar (222nd in leap years), with 144 days remaining. ... A digital object identifier (or DOI) is a permanent identifier (permalink) given to a World Wide Web file or other Internet document so that if its Internet address changes, users will be redirected to its new address. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 9 is the 221st day of the year in the Gregorian Calendar (222nd in leap years), with 144 days remaining. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 10 is the 222nd day of the year (223rd in leap years) in the Gregorian Calendar. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 9 is the 221st day of the year in the Gregorian Calendar (222nd in leap years), with 144 days remaining. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 10 is the 222nd day of the year (223rd in leap years) in the Gregorian Calendar. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 15 is the 227th day of the year in the Gregorian Calendar (228th in leap years), with 138 days remaining. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 10 is the 222nd day of the year (223rd in leap years) in the Gregorian Calendar. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 15 is the 227th day of the year in the Gregorian Calendar (228th in leap years), with 138 days remaining. ... A digital object identifier (or DOI) is a permanent identifier (permalink) given to a World Wide Web file or other Internet document so that if its Internet address changes, users will be redirected to its new address. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 24 is the 236th day of the year in the Gregorian Calendar (237th in leap years), with 129 days remaining. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 16 is the 228th day of the year (229th in leap years) in the Gregorian Calendar. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 18 is the 230th day of the year (231st in leap years) in the Gregorian calendar. ... A digital object identifier (or DOI) is a permanent identifier (permalink) given to a World Wide Web file or other Internet document so that if its Internet address changes, users will be redirected to its new address. ... A digital object identifier (or DOI) is a permanent identifier (permalink) given to a World Wide Web file or other Internet document so that if its Internet address changes, users will be redirected to its new address. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 21 is the 233rd day of the year (234th in leap years) in the Gregorian Calendar. ... A digital object identifier (or DOI) is a permanent identifier (permalink) given to a World Wide Web file or other Internet document so that if its Internet address changes, users will be redirected to its new address. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... August 18 is the 230th day of the year (231st in leap years) in the Gregorian calendar. ...

External links

• Future Location of Barnard's star (with animated picture)
• Jack Schmidling amateur photography
• V2500 Oph. SIMBAD. Retrieved on 14 April 2006.
• ARICNS 4C01453. ARICNS. Retrieved on 14 April 2006.