HD 98649

HD 98649
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Crater
Right ascension 11h 20m 51.769s[1]
Declination –23° 13 02.43[1]
Apparent magnitude (V) +8.00
Characteristics
Spectral type G4V
Astrometry
Proper motion (μ) RA: –199.28 ± 0.57[1] mas/yr
Dec.: –177.51 ± 0.48[1] mas/yr
Parallax (π)24.08 ± 0.79[1] mas
Distance135 ± 4 ly
(42 ± 1 pc)
Details
Mass1 ± 0.03 M
Radius1 R
Luminosity0.86 L
Surface gravity (log g)4.38 ± 0.08 cgs
Temperature5759 ± 35 K
Metallicity [Fe/H]0.02 ± 0.03 dex
Age2.3 ± 2.0 Gyr
Other designations
HIP 55409, LTT 4199
Database references
SIMBADdata
Exoplanet Archivedata
Extrasolar Planets
Encyclopaedia
data

HD 98649 is a G-class yellow dwarf star.

Planetary system

From 1998 to 2012, the star was under observance from "the CORALIE echelle spectrograph at La Silla Observatory".

In 2012, a long-period, wide-orbiting planet was deduced by radial velocity. This was published in November.

The discoverers noted, "HD 98649b is in the top five of the most eccentric planetary orbit and the most eccentric planet known with a period larger than 600 days." The reason for this eccentricity is unknown. They also submit it as a "candidate for direct imaging", once it gets out to "10.4 AU at apoastron" and 250 milliarcseconds of separation relative to Earth.[2]

The HD 98649 planetary system[3]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b >6.8 ± 0.5 MJ 5.6 ± 0.4 4951+607
465
0.85 ± 0.05

References

  1. 1 2 3 4 5 van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.Vizier catalog entry
  2. Marmier, M.; et al. (2013). "The CORALIE survey for southern extrasolar planets XVII. New and updated long period and massive planets". Astronomy and Astrophysics 551. A90. arXiv:1211.6444. Bibcode:2013A&A...551A..90M. doi:10.1051/0004-6361/201219639.
  3. "hd_98649_b".


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