HD 75289

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HD 75289
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Vela
Right ascension 08h 47m 40.3894s
Declination –41° 44′ 12.452″
Apparent magnitude (V) 6.36
Characteristics
Spectral type G0V
B−V color index 0.58
Astrometry
Radial velocity (Rv) +14 km/s
Proper motion (μ) RA: –20.50 mas/yr
Dec.: –227.68 mas/yr
Parallax (π) 34.55 ± 0.56 mas
Distance 94 ± 2 ly
(28.9 ± 0.5 pc)
Absolute magnitude (MV) 4.05
Details
Mass 1.05 M
Radius 1.25 R
Luminosity 1.82 L
Surface gravity (log g) 4.25 cgs
Temperature 6011 K
Metallicity 0.29
Rotation ~24.6
Age 4.96 years
Other designations

HD 75289 is a 6th magnitude star in the constellation of Vela. Like our Sun, it is a yellow dwarf but slightly more massive, hotter and luminous. The spectral type of the star is G0 V. Under exceptionally good circumstances it might be visible to the unaided eye; however, usually binoculars are needed.

In 2004, a possible red dwarf companion was detected.

Planetary system[edit]

In 1999 a planet HD 75289 b with half the mass of Jupiter was detected by radial velocity method.[1] This planet is a typical hot Jupiter that takes only about 3.51 days to revolve at an orbital distance of 0.0482 AU.

The HD 75289 planetary system[2]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b >0.467 ± 0.041 MJ 0.0482 ± 0.0028 3.509267 ± 0.000064 0.034 ± 0.029


HD 75289 B[edit]

HD 75289 B
Observation data
Epoch 2000      Equinox 2000
Constellation Vela
Right ascension 8h 47m 42.24s
Declination -41° 44' 7.70"
Apparent magnitude (V)  ?
Distance 94.36? ly
(28.94? pc)
Spectral type M2-M5 V
Other designations
n/a

HD 75289 B is a possible red dwarf star orbiting HD 75289. The stars share the same proper motion so they are probably related. Apparent distance between the two stars is about 21.5 arcseconds, at a distance of 94 light years that would be 621 astronomical units. However, the radial distance between the stars is unknown, so they are probably further apart. In any case, one revolution around the primary would take thousands of years to complete.

The study that found the red dwarf also rules out any further stellar companions beyond 140 AU and massive brown dwarf companions from 400 AU up to 2000 AU.


References[edit]

  1. ^ Udry, S. et al. (2000). "The CORALIE survey for southern extra-solar planets II. The short-period planetary companions to HD 75289 and HD 130322". Astronomy and Astrophysics 356 (2): 590–598. Bibcode:2000A&A...356..590U. 
  2. ^ Butler, R. P. et al. (2006). "Catalog of Nearby Exoplanets". The Astrophysical Journal 646 (1): 505–522. arXiv:astro-ph/0607493. Bibcode:2006ApJ...646..505B. doi:10.1086/504701. 

External links[edit]

Coordinates: Sky map 08h 47m 40.3894s, −41° 44′ 12.452″