Gliese 570

Coordinates: Sky map 14h 57m 28.00144s, −21° 24′ 55.7131″
Source: Wikipedia, the free encyclopedia.
Gliese 570
Gliese 570
The quaternary star system Gliese 570. The T-type methane brown dwarf Gliese 570D is indicated with an arrow.
Credit: 2MASS
Location of Gliese 570 (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Libra
Right ascension 14h 57m 28.00144s[1]
Declination −21° 24′ 55.7131″[1]
Apparent magnitude (V) 5.75 / 8.07 / 10.5
Characteristics
Spectral type K4V / M1V / M3V / T7V
U−B color index 1.06 /1.22
B−V color index 1.11 / 1.51
Variable type None
Distance
19.199 ± 0.007 ly
(5.886 ± 0.002 pc)
Absolute magnitude (MV)6.89[3]
BC
Distance
approx. 19 ly
(approx. 5.9 pc)
Absolute magnitude (MV)9.19[3] / 11.05
D
Distance
19.3 ± 0.2 ly
(5.91 ± 0.06 pc)
Absolute magnitude (MV)11.05[citation needed]
Details
Mass0.802 ± 0.040[7] / 0.55 / 0.35 / 0.05 M☉
Radius0.739 ± 0.019[7] / 0.65 R☉
Luminosity (bolometric)0.22[note 1] / 0.04 / ? / 3•10−6[8] L☉
Luminosity (visual, LV)0.16 / 0.02 / 0.003 / ? L☉
Temperature4597 ± 101[7] / 2700 K
Metallicity
Rotational velocity (v sin i)
1.50[7] km/s
BD-20°4123, SAO 183039, LFT 1160, LPM 550
D: 2MASS J14571496-2121477
Database references
Exoplanet Archive
data
ARICNSdata

Gliese 570 (or 33 G. Librae) is a quaternary

extrasolar planet
was thought to orbit the primary star, but it was discounted in 2000.

Distance and visibility

In the night sky, the Gliese 570 system lies in the southwestern part of Libra. The system is southwest of Alpha Librae and northwest of Sigma Librae. In the early 1990s, the European Hipparcos mission measured the parallax of components B and C, suggesting that the system was at a distance of 24.4 light-years from the Sun. This, however, was a relatively large error as Earth-based parallax and orbit observations suggest that the two stars are actually part of a system with Gliese 570 A, and must actually lie at the same distance.

Star system

The primary star of the system (component A) is an

spectral type K4V and emits X-rays.[10] Radial velocities of the primary obtained in the course of an extrasolar planet search at Lick Observatory show a linear trend probably due to the orbital motion of the Gliese 570 BC system around the primary.[11]

A binary system in their own right, components B and C are both rather dim

spectral type M3V, and both emit X-rays.[10]

An artist's impression of Gliese 570 D showing the primary stars

On January 15, 2000, astronomers announced that they had found one of the coolest

brown dwarfs then known. Catalogued as Gliese 570 D, it was observed at a wide separation of more than 1,500 astronomical unit from the triple star system.[12] It has an estimated mass of 50 times that of Jupiter
.

The status of Gliese 570 D as a

Cerro Tololo Interamerican Observatory in Chile. The surface temperature of this substellar object was found to be a relatively cool 500 degrees Celsius, making it cooler and less luminous than any other then-known brown dwarf (including the prototype "T" dwarf), and classifying the object as a T7-8V brown dwarf. No X-rays have been reported from this brown dwarf
.

Search for planets

In 1998, an

extrasolar planet was announced to orbit the primary star within the Gliese 570 system. The planet, identified as "Gliese 570 Ab", was considered doubtful and the claim was retracted in 2000.[13]
No extrasolar planets have been confirmed to exist in this multiple star system thus far.

See also

Notes

  1. Stefan–Boltzmann constant
    .

References

  1. ^
    S2CID 18759600
  2. ^
    S2CID 244398875
    . Gaia DR3 record for this source at VizieR.
  3. ^
    S2CID 118577511
    .
  4. Bibcode:1967IAUS...30...57E
    .
  5. ^
    S2CID 119287203
    .
  6. S2CID 18160586
    .
  7. ^
    S2CID 14786643
    .
  8. S2CID 18779443
  9. ^ "Sixth Catalog of Orbits of Visual Binary Stars". Archived from the original on 2009-04-12. Retrieved 2008-05-18.
  10. ^
    doi:10.1086/176149
    .
  11. S2CID 118503912
    .
  12. S2CID 19109066
    .
  13. Bibcode:2000A&A...362..585E. Archived from the original
    on 2012-02-08. Retrieved 2007-08-19.

External links
Retrieved from "https://en.wikipedia.org/w/index.php?title=Gliese_570&oldid=1186872902"