HD 48948

HD 48948

Observation data Epoch J2000        Equinox J2000
Constellation	Lynx [1]
Right ascension	06h 49m 57.0256s [2]
Declination	+60° 20′ 07.9606″ [2]
Apparent magnitude  (V)	8.58 [3]
Characteristics
Evolutionary stage	Main sequence star
Spectral type	K3V [4]
Apparent magnitude  (J)	6.33±0.02 [3]
Apparent magnitude  (H)	5.73±0.02 [3]
Apparent magnitude  (K)	5.61±0.02 [3]
B−V color index	1.21 [3]
Astrometry
Radial velocity (Rv)	−52.58±0.12 [2] km/s
Proper motion (μ)	RA: 253.401 mas/yr [2] Dec.: 410.798 mas/yr [2]
Parallax (π)	59.3934±0.0228  mas [2]
Distance	54.91 ± 0.02  ly (16.837 ± 0.006  pc)
Absolute magnitude  (MV)	7.46±0.05 [5]
Details [3]
Mass	0.686+0.020 −0.013  M☉
Radius	0.679±0.004  R☉
Luminosity	0.156 [6]   L☉
Temperature	4593±60  K
Metallicity [Fe/H]	−0.21±0.03  dex
Rotation	43.45+1 −0.71 d
Rotational velocity (v sin i)	<2 km/s
Age	11.48+1.93 −4.67  Gyr
Other designations
BD+60°1003, GJ 247, HD 48948, HIP 32769, SAO 13971, G 250-22, L 1815-6, LHS 6111, TYC 4097-1471-1, 2MASS J06495699+6020077 [7]
Database references
SIMBAD	data
Exoplanet Archive	data

HD 48948 is a K-type main-sequence star located in the constellation Lynx, approximately 55 light years away, based on a parallax of 59.393 mas. At an apparent magnitude of 8.58, it is too faint to be seen with the naked eye. ^[3]

It has a stellar classification of K3V, which classifies it as a main sequence star (like the Sun) fusing atoms of hydrogen into helium at its core. Estimated to be 11.5 billion years old, HD 48948 has 0.68 times the mass and radius of the Sun. Its surface has an effective temperature of 4,593  K, ^[3] giving it the orange glow of a K-type star. ^[8]

Planetary system

In 2024, three planets were discovered orbiting HD 48948 via radial velocity using the HARPS-N spectrograph, with orbital periods of 7.3, 38 and 151 days, respectively, ^[9] derived from 189 measurements over a 9.5-year period from 6 October 2013 to 16 April 2023. Of the three planets, the outermost planet, HD 48948 d, a super-Earth weighing 10.59±1.00 Earth masses, is located within the habitable zone. ^[10]

The HD 48948 planetary system ^[3]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	>4.88±0.21  M🜨	0.0652±0.0005	7.34013±0.00040	0.078+0.058 −0.050	—	—
c	>7.27±0.70  M🜨	0.1951±0.0016	37.920+0.026 −0.024	0.22+0.10 −0.11	—	—
d	>10.59±1.00  M🜨	0.4894±0.0042	150.95+0.45 −0.41	0.12+0.12 −0.08	—	—

References

1. 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. 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. Dalal, S.; et al. (37) (24 June 2024). "Trio of super-Earth candidates orbiting K-dwarf HD 48948: a new habitable zone candidate". Monthly Notices of the Royal Astronomical Society. 531 (4): 4464–4481. doi: 10.1093/mnras/stae1367 . hdl: 10023/30204 .
4. Grieves, N; Ge, J; Thomas, N; Willis, K; Ma, B; Lorenzo-Oliveira, D; Queiroz, A B A; Ghezzi, L; Chiappini, C; Anders, F; Dutra-Ferreira, L; Porto de Mello, G F; Santiago, B X; da Costa, L N; Ogando, R L C (2018-12-11). "Chemo-kinematics of the Milky Way from the SDSS-III MARVELS survey". Monthly Notices of the Royal Astronomical Society. 481 (3): 3244–3265. arXiv: 1803.11538 . doi: 10.1093/mnras/sty2431 . ISSN   0035-8711.
5. Holmberg, J.; Nordström, B.; Andersen, J. (2009-07-01). "The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics". Astronomy and Astrophysics. 501 (3): 941–947. arXiv: 0811.3982 . Bibcode:2009A&A...501..941H. doi:10.1051/0004-6361/200811191. ISSN   0004-6361. HD 48948's database entry at VizieR.
6. McDonald, I.; Zijlstra, A. A.; Watson, R. A. (2017-10-01), "Fundamental parameters and infrared excesses of Tycho-Gaia stars", Monthly Notices of the Royal Astronomical Society, 471: 770–791, arXiv: 1706.02208 , doi: 10.1093/mnras/stx1433 , ISSN   0035-8711 HD 48948' database entry at VizieR.
7. "HD 48948". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 9 July 2024.
8. "The Colour of Stars". Australia Telescope, Outreach and Education. Commonwealth Scientific and Industrial Research Organisation. December 21, 2004. Archived from the original on 2013-12-03. Retrieved 2012-01-16.
9. Cowing, Keith (26 June 2024). "Three Potential Super-Earths Discovered Around Nearby Star HD 48 948". Astrobiology. Retrieved 11 July 2024.
10. Luntz, Stephen (25 June 2024). "Nearest Super-Earth In A Habitable Zone Orbit Announced". IFLScience. Retrieved 11 July 2024.