Gliese 445

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Gliese 445
PIA17461 Heading toward Gliese 445 (annotated).jpg
Image of AC +79 3888 (circled), also known as Gliese 445, located 17.6 light-years from Earth. NASA's Voyager 1 spacecraft, which is out of our solar system, is headed toward an encounter with the star. In about 40,000 years, Voyager 1 will be closer to this star than our own sun.[1]
Credit: Caltech/Palomar
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Camelopardalis
Right ascension 11h 47m 41.3771s[2]
Declination +78° 41′ 28.178″[2]
Apparent magnitude (V) 10.78[2]
Spectral type M3.5[2]
B−V color index 1.6[2]
V−R color index 0.8[2]
R−I color index 0.8[2]
Radial velocity (Rv) −119[2] km/s
Proper motion (μ) RA: 743.58[2] mas/yr
Dec.: 480.47[2] mas/yr
Parallax (π) 185.52 ± 1.43[2] mas
Distance 17.6 ± 0.1 ly
(5.39 ± 0.04 pc)
Mass 0.15[3]–0.30[4] M
Radius 0.320[4] R
Other designations
Gliese 445, Gl 445, G 254-29, AC+79 3888, HIP 57544, LFT 849, LHS 2459, LTT 13235, NLTT 28539,[2] PLX 2722
Database references
PIA17461 Heading toward Gliese 445 (annotated).jpg

Gliese 445 (Gl 445) is an M-type main sequence star in the constellation of Camelopardalis, close to Polaris. It is currently 17.6 light-years from the Sun and has an apparent magnitude of 10.8.[2] It is visible from north of the Tropic of Cancer all night long, but not to the naked eye.[5] Because the star is a red dwarf with a mass only a quarter to a third of that of our Sun, scientists question the ability of this system to support life.[5] Gliese 445 is also a known X-ray source.[6]

The Voyager 1 probe will pass within 1.6 light-years of Gliese 445 in about 40,000 years.[7] However, by that time the probe will no longer be operational. Also, given the star's inherent low brightness, even at that distance it would be barely visible to the naked eye of a hypothetical human being, with an apparent magnitude of only 5.72.

Solar encounter[edit]

Distances of the nearest stars from 20,000 years ago until 80,000 years in the future

While the Voyager probe flies through space slowly closing on Gliese 445, the star is rapidly approaching the Sun. At the time the probe passes Gliese 445, the star will be about 1.059 parsecs (3.45 light-years) from the Sun,[3] but with less than half the brightness necessary to be seen with the naked eye.[5] But the dwarf star will still be farther away than other stars have achieved.


  1. ^
  2. ^ a b c d e f g h i j k l m LHS 2459 -- High proper-motion Star, database entry, SIMBAD. Accessed on line July 29, 2008.
  3. ^ a b Bobylev, Vadim V. (March 2010). "Searching for Stars Closely Encountering with the Solar System". Astronomy Letters. 36 (3): 220–226. Bibcode:2010AstL...36..220B. arXiv:1003.2160Freely accessible. doi:10.1134/S1063773710030060. 
  4. ^ a b AC+79 3888, entry, Catalogue of nearest stars until 10pc, V. A. Zakhozhaj, CDS ID V/101.
  5. ^ a b c Page 168, Planets Beyond: Discovering the Outer Solar System, Mark Littmann, Mineola, New York: Courier Dover Publications, 2004, ISBN 0-486-43602-0.
  6. ^ Schmitt JHMM; Fleming TA; Giampapa MS (September 1995). "The X-Ray View of the Low-Mass Stars in the Solar Neighborhood". Ap J. 450 (9): 392–400. Bibcode:1995ApJ...450..392S. doi:10.1086/176149. 
  7. ^ NASA – Voyager - Mission - Interstellar Mission

External links[edit]

  • Wikisky image of TYC 4553-192-1 (Gliese 445)