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V 2500 Oph - Barnard's star and its proper
movement |
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Description of object:
V 2500 Oph - Barnards Star
Barnards Star is a faint star in the
constellation of the Serpens. With a distance of 5.94 (+/- 0.022) light-years
Barnard's Star is the fourth closest to the solar system among the known stars.
Only alpha, beta and Proxima Centauri are closer. Barnard's Star is a slightly
variable red dwarf star of spectral type M5 and a visual magnitude of 9.6mag.
It has only the 0.00044 luminosity of our Sun and is close to the star 66
Ophiuchus. By the year 11,800 it will approach the Sun up to 3.8 light-years
and will then be the nearest fixed star to the Sun for some time.
The
star has the highest known proper motion to date of RA = 0.8" and DE = 10.3"
and moves at 140 kilometers per hour relative to our solar system. The large
proper motion was discovered in 1916 by astronomer Edward Emerson Barnard.
Barnard's star caused a sensation in the 1960s when astronomer Peter
van de Kamp announced the first discovery of a Jupiter-sized extrasolar planet
orbiting the star. Observations of it were based on high-precision parallax
measurements over many years, but it could never be confirmed.
All the
more surprising in the fall of 2018, then, came the ESO announcement of the
discovery of a planet orbiting Barnard's Arrow Star. The planet, referred to as
Barnard's Star B, is now the second closest known exoplanet - besides Proxima
Centauri B - to Earth. The data collected suggest the planet could be a
super-Earth, with a mass at least 3.2 times that of Earth, which orbits
Barnard's Arrow Star in about 233 days.
For more details, see the ESO press release.
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The proper motion of Barnard's star between
2005 and 2019
In addition to Proxima Centauri C, we have also
taken image series of Barnard's star irregularly since the year 2002 to
document its fast proper motion.
« The animation on the left shows the proper
motion of Barnard's Arrow star between the years 2005 (with image marks) and
2019.
Image data: (image orientation
south top and west right).
2005: SBIG ST2000-XM and 6" Zeiss APQ refractor
at f = 1,200 mm. 07.08.2005 - 20:00 UT, exposure 600 seconds. Observing site:
Rooisand Observatory.
2019: ASI 071 Pro and 130mm Astro
Physics refractor at f = 850 mm. 2019/09/30 - 20:30 UT, exposure 10 x 180 sec.
Observing site: Onjala Observatory. |
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The proper motion of Barnard's star between
2002 and 2005
» The
animation on theright shows the proper motion of Proxima Centauri towards the
distant background stars between the years 2002 and 2005 in two images
Image
data (image orientation south top and west right)
2002: SBIG ST10-XME (pixel size 6.8 x 6.8
mü) and 5" Vixen ED refractor at f = 860 mm. 12.08.2002 - 21:30 UT,
exposure 180 seconds. Observing site: Tivoli Guest Lodge- The raw image in 2002
was taken in very poor seeing and poor sky transparency.
2005: SBIG
ST2000-XM (pixel size 7.4 x 7.4 mü) and 6" Zeiss APQ refractor at f =
1,200 mm. 07.08.2005 - 20:00 UT, exposure 600 seconds. Observation site:
Rooisand Observatory.
Click
here or the thumbnail to load a large image animation. |
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All Images and all Content are ©
by Franz Hofmann + Wolfgang Paech |