HD 137010

HD 137010

2MASS image of HD 137010
Observation data
Epoch J2000      Equinox J2000
Constellation Libra[1]
Right ascension 15h 24m 21.25106s[2]
Declination −19° 44′ 21.6785″[2]
Apparent magnitude (V) 10.14[3]
Characteristics
Evolutionary stage Main sequence
Spectral type K3.5 V[3]
Astrometry
Radial velocity (Rv)+27.866[3] km/s
Proper motion (μ) RA: +228.536[2] mas/yr
Dec.: −248.158[2] mas/yr
Parallax (π)22.2922±0.0174 mas[2]
Distance146.3 ± 0.1 ly
(44.86 ± 0.04 pc)
Absolute magnitude (MV)+7.2[1]
Details
Mass0.726±0.017[4] M☉
Radius0.707±0.023[4] R☉
Luminosity0.232+0.023
−0.021
[4] L☉
Surface gravity (log g)4.60±0.03[4] cgs
Temperature4,770±90[4] K
Metallicity [Fe/H]-0.22[4] dex
Age4.8-10[4] Gyr
Other designations
BD−19 4097, HD 137010, HIP 75398, PPM 230195, EPIC 249661074[5][4], TIC 428919267
Database references
SIMBADdata

HD 137010 (also known as EPIC 249661074) is a solar analog star located approximately 146 light-years away in the zodiac constellation of Libra. Its apparent visual magnitude is 10.14, making it invisible to the naked eye but observable with a standard telescope[3]. It likely has an orbiting exoplanet, known as HD 137010 b, which may be a very Earth-like exoplanet in terms of orbital characteristics but cooler than Earth.[6][4]

Stellar characteristics

[edit]

HD 137010 has a spectral type of K3.5 V,[7] indicating that it is a main-sequence star generating energy through the thermonuclear fusion of hydrogen in its core. This energy is radiated from its outer envelope at an effective temperature of around 4770 K, giving it an orange hue. Its age is estimated to be between 4.80 and 10.0 billion years. HD 137010 is slightly smaller than the Sun, with a mass of approximately 72.6% of the Sun's mass and a radius of 70.7% of the Sun's radius.[5][4]

Planetary system

[edit]
Inset focusing on the transit event.

HD 137010 was observed by the Kepler space telescope for 88 days in 2017 during the K2 mission. Its photometry shows the presence of a single transit during this period. It is possible to rule out that this detection is a false positive and it is therefore not an instrumental error, nor contamination of the light curve due to the presence, for example, of a nearby eclipsing binary.[4] This transit was therefore very likely produced by a genuine exoplanet, then designated HD 137010 b, even though it remains only a candidate in the absence of further transits or independent confirmation by another detection method.[6]

In early 2026, an analysis of archival data obtained during the 15th campaign of the K2 mission of the Kepler Space Telescope in 2017 revealed a single 10-hour transit event that occurred on the K-type dwarf star HD 137010 with an apparent magnitude of 10.1.[4] The transit was relatively shallow (225±10 ppm), but detectable with a high signal-to-noise ratio due to the exceptionally high photometric precision achieved for the target object. Analysis of K2 photometry, historical and new observations, as well as archival radial velocities and astrometry, strongly indicates that the event was astrophysical in nature, occurred directly on the target object, and is best explained by the transit of a candidate planet.[6][4]

The single observed transit implies a radius of 1.06 R🜨, a negligibly small orbital eccentricity, and an orbital period of 355 days (0.88 AU). The predicted incident flux is 0.29+0.11
−0.13
I⊕.[5][4] This means that HD 137010 b is located at the outer edge of the habitable zone.[4]

The HD 137010 planetary system[5][4]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b (unconfirmed) 0.88+0.3
−0.1
355.0+200.0
−59.0
0 >89.82+0.05
−0.03
°
1.06+0.06
−0.05
 R🜨

References

[edit]
  1. ^ a b Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. XHIP record for this object at VizieR.
  2. ^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  3. ^ a b c d "SIMBAD Results for HD 137010". SIMBAD. Retrieved 2026-01-27.
  4. ^ a b c d e f g h i j k l m n o p Venner, Alexander; Vanderburg, Andrew; X. Huang, Chelsea; Dholakia, Shishir; Schwengeler, Hans Martin; Howell, Steve B.; Wittenmyer, Robert A.; Kristiansen, Martti H.; Omohundro, Mark; Terentev, Ivan A. (2026). "A Cool Earth-sized Planet Candidate Transiting a Tenth Magnitude K-dwarf From K2". The Astrophysical Journal. 997 (2): L38. arXiv:2601.19870. Bibcode:2026ApJ...997L..38V. doi:10.3847/2041-8213/adf06f.
  5. ^ a b c d Martin, Pierre-Yves (2026). "Planet HD 137010 b". exoplanet.eu. Retrieved 2026-01-28.
  6. ^ a b c "Discovery Alert: An Ice-Cold Earth? - NASA Science". 2026-01-27. Retrieved 2026-01-27.
  7. ^ Gray, R. O.; Corbally, C. J.; Garrison, R. F.; McFadden, M. T.; Bubar, E. J.; McGahee, C. E.; O'Donoghue, A. A.; Knox, E. R. (July 2006). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc--The Southern Sample". The Astronomical Journal. 132 (1): 161–170. doi:10.1086/504637. ISSN 0004-6256.

This article is sourced from Wikipedia. Content is available under the Creative Commons Attribution-ShareAlike License.