Gliese 3470

GJ 3470 is a red dwarf star located in the constellation of Cancer, 30 parsecs away from Earth.[4]

Gliese 3470

GJ 3470
Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Cancer[1]
Right ascension	07^h 59^m 05.8395618539^s[2]
Declination	15° 23′ 29.240025256″[2]
Apparent magnitude (V)	12.330[3]
Characteristics
Evolutionary stage	Main sequence red dwarf
Spectral type	M2.0Ve[2]
Apparent magnitude (B)	13.5[2]
Apparent magnitude (V)	12.330[3]
Apparent magnitude (R)	11.934[2]
Apparent magnitude (J)	8.794[2]
Apparent magnitude (H)	8.206[2]
Apparent magnitude (K)	7.989[2]
B−V color index	1.17
V−R color index	0.396
J−H color index	0.588
J−K color index	0.217
Astrometry
Radial velocity (Rv)	26.341±0.0038[2] km/s
Proper motion (μ)	RA: -185.734[2] mas/yr Dec.: -57.263[2] mas/yr
Parallax (π)	33.9601 ± 0.0582[2] mas
Distance	96.0 ± 0.2 ly (29.45 ± 0.05 pc)
Details[3]
Mass	0.539+0.047 −0.043 M☉
Radius	0.547±0.018 R☉
Surface gravity (log g)	4.695±0.046 cgs
Temperature	3600±100 K
Metallicity [Fe/H]	0.20±0.10 dex
Other designations
GJ 3470, LP 424-4, NLTT 18739, 2MASS J07590587+1523294[2]
Database references
SIMBAD	data
Exoplanet Archive	data

History

The star has a mass of 0.539 solar masses and a radius of 0.547 solar radii.[3]

It is 1.6 billion years old, with a metallicity of 0.2 Fe/H.[5]

Planetary system

At least one exoplanet has been discovered orbiting at the distance of 0.031 astronomical units.[6]

The exoplanet, which is called GJ 3470 b, is a mini-Neptune with an orbital period of 3.3 days.[6]

In July 2020, a group of amateur astronomers reported a new exoplanet candidate, which is the size of Saturn and inside the system's habitable zone, along with twelwe tentative transits from not yet characterized exoplanets in same star system.[7][8] If confirmed, GJ 3470 c would become the second exoplanet discovered by amateur astronomers, after KPS-1b, an exoplanet discovered by Ural State Technical University using amateur data.[9] The new GJ 3470 candidate was discovered with amateur data and through a project led by amateur astronomers.[10][11][12][13][14][15][16]

The Gliese 3470 planetary system[6][7]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	12.57±1.3 M⊕	0.031±	3.3366487^+0.0000043 −0.0000033	0.114±0.052	88.88^+0.62 −0.45°	4.199±0.58 R⊕
c (unconfirmed)	—	0.25	66	—	—	9.2 R⊕

See also

• GJ 3470 b

References

1. Staff (2 August 2008). "Finding the constellation which contains given sky coordinates". DJM.cc. Retrieved 16 July 2020.
2. "LP 424-4 -- High proper-motion Star". SIMBAD. Centre de Données astronomiques de Strasbourg. Retrieved 16 July 2020.
3. "GJ 3470". NASA Exoplanet Archive. Retrieved 16 July 2020.
4. "GJ 3470". www.exoplanetkyoto.org. Retrieved 2020-07-16.
5. "The Extrasolar Planet Encyclopaedia — GJ 3470 b". exoplanet.eu. Retrieved 2020-07-16.
6. Bonfils, X.; Gillon, Michaël; Udry, S.; Armstrong, D.; Bouchy, F.; Delfosse, X.; Forveille, T.; Fumel, Aurélie; Jehin, Emmanuel; Lendl, M.; Lovis, C. (2012-10-01). "A hot Uranus transiting the nearby M dwarf GJ 3470. Detected with HARPS velocimetry. Captured in transit with TRAPPIST photometry". Astronomy and Astrophysics. 546. doi:10.1051/0004-6361/201219623. ISSN 0004-6361.
7. Scott, Phillip; Walter, Bradley; Ye, Quanzhi; Mitchell, David; Heiland, Leo; Gao, Xing; Palado, Alejandro; Otabek, Burkhonov; Casal, Jesus Delgado; Hill, Colin; Garcia, Alberto (2020-07-14). "GJ 3470 c: A Saturn-like Exoplanet Candidate in the Habitable Zone of GJ 3470". arXiv:2007.07373 [astro-ph].
8. "The Extrasolar Planet Encyclopaedia — GJ 3470 c". exoplanet.eu. Retrieved 2020-07-16.
9. Burdanov, Artem; et al. (July 2018). "KPS-1b: The First Transiting Exoplanet Discovered Using an Amateur Astronomer's Wide-field CCD Data". Publications of the Astronomical Society of the Pacific. 130 (989): 074401. arXiv:1804.05551. Bibcode:2018PASP..130g4401B. doi:10.1088/1538-3873/aabde2.
10. Scott, Phillip; Walter, Bradley; Ye, Quanzhi; Mitchell, David; Heiland, Leo; Gao, Xing; Palado, Alejandro; Otabek, Burkhonov; Casal, Jesus Delgado; Hill, Colin; Garcia, Alberto (2020-07-14). "GJ 3470 c: A Saturn-like Exoplanet Candidate in the Habitable Zone of GJ 3470". arXiv:2007.07373 [astro-ph].
11. Carter, Jamie. "Inside The 24/7 Search For Another Habitable Planet Within 100 Light Years Of Earth". Forbes. Retrieved 2020-07-19.
12. Maloney, Dan (2020-07-19). "Hackaday Links: July 19, 2020". Hackaday. Retrieved 2020-07-20.
13. "Saturn-Like Exoplanet Found in Habitable Zone of Gliese 3470 | Astronomy | Sci-News.com". Breaking Science News | Sci-News.com. Retrieved 2020-07-21.
14. Editor, James Beaty Managing. "Local astronomer says he's detected new planet". McAlester News-Capital. Retrieved 2020-07-22.CS1 maint: extra text: authors list (link)
15. "Amateur-team spoort (mogelijke) nieuwe exoplaneet op - Astronomie.nl". www.astronomie.nl. Retrieved 2020-07-24.
16. Andy Tomaswick (2020-07-28). "Saturn-sized Planet Found in the Habitable Zone of Another Star. The First Planet Completely Discovered by Amateur Astronomers". Universe Today. Retrieved 2020-07-29.