37 Geminorum

37 Geminorum
Observation data
Epoch J2000      Equinox J2000
Constellation Gemini
Right ascension 06h 55m 18.66757s[1]
Declination +25° 22′ 32.5153 ″[1]
Apparent magnitude (V) 5.73[2]
Characteristics
Spectral type G0 V[3]
U−B color index +0.01[2]
B−V color index 0.599[4]
Astrometry
Radial velocity (Rv)-11.3[5] km/s
Proper motion (μ) RA: -35.91[1] mas/yr
Dec.: +25.65[1] mas/yr
Parallax (π)58.00 ± 0.40[1] mas
Distance56.2 ± 0.4 ly
(17.2 ± 0.1 pc)
Details
Luminosity1.22[6] L☉
Surface gravity (log g)4.29[3] cgs
Temperature5,874[7] K
Metallicity [Fe/H]-0.25[7] dex
Rotational velocity (v sin i)1.89[4] km/s
Age5.49[8] Gyr
Other designations
BD +25°1496, GCTP 1613.02, Gl 252, HD 50692, HIP 33277, HR 2569, SAO 78866.[9]

37 Geminorum is a star located at the northwest part of the northern zodiac constellation of Gemini. Its distance from the Sun is about 56.2 light years. It is a solitary, G-type main sequence star with a stellar classification of G0 V. No extrasolar planets have yet been discovered around it.

37 Geminorum has many physical properties in common with the Sun and is one of the nearest solar analogs. Due to this fact some scientists believe that the prospects for life in its vicinity are good. In September 2003, 37 Geminorum was identified by astrobiologist Margaret Turnbull from the University of Arizona in Tucson as one of the most promising nearby candidates for hosting life, based on her analysis of the HabCat list of stars.

There was a METI message sent to 37 Geminorum. It was transmitted from Eurasia's largest radar, 70-meter Yevpatoria Planetary Radar. The message was named the Teen Age Message, it was sent on September 3, 2001, and it will arrive at 37 Geminorum in December 2057.[10]

Sun comparison

This chart compares the sun to 37 Geminorum.

Identifier J2000 Coordinates Distance
(ly)		 Stellar
Class		 Temperature
(K)		 Metallicity
(dex)		 Age
(Gyr)		 Notes
Right ascension Declination
Sun — — 0.00 G2V 5,778 +0.00 4.6 [11]
37 Geminorum [12] 06h 55m 18.66s +25° 22′ 32.51″ 56.2 G0 V 5,874 +0.023 5.49

To date no solar twin with an exact match as that of the Sun has been found, however, there are some stars that come very close to being identical to that of the Sun, and are such considered solar twins by the majority of the public. An exact solar twin would be a G2V star with a 5,778K temperature, be 4.6 billion years old, with the correct metallicity and a 0.1% solar luminosity variation.[13] Stars with an age of 4.6 billion years are at the most stable state. Proper metallicity and size are also very important to low luminosity variation.[14][15][16]

Morgan-Keenan spectral classification of stars. Most common star type in the universe are M-dwarfs, 76%. The sun is a 4.6 billion year-old G-class (G2V) star and is more massive than 95% of all stars. Only 7.6% are G-class stars

See also

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:0708.1752Freely accessible, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357.
  2. 1 2 Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV data, SIMBAD, Bibcode:1986EgUBV........0M.
  3. 1 2 Gray, R.O.; et al. (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, arXiv:astro-ph/0603770Freely accessible, Bibcode:2006AJ....132..161G, doi:10.1086/504637.
  4. 1 2 Martínez-Arnáiz, R.; et al. (September 2010), "Chromospheric activity and rotation of FGK stars in the solar vicinity. An estimation of the radial velocity jitter", Astronomy and Astrophysics, 520: A79, arXiv:1002.4391Freely accessible, Bibcode:2010A&A...520A..79M, doi:10.1051/0004-6361/200913725.
  5. ↑ Wilson, R. E. (1953), General Catalogue of Stellar Radial Velocities, Carnegie Institute of Washington D.C., Bibcode:1953GCRV..C......0W.
  6. ↑ McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037Freely accessible, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x.
  7. 1 2 Holmberg, J.; et al. (2009), "The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics", Astronomy and Astrophysics, 501 (3): 941–947, arXiv:0811.3982Freely accessible, Bibcode:2009A&A...501..941H, doi:10.1051/0004-6361/200811191. See Vizier catalogue V/130.
  8. ↑ Vican, Laura (June 2012), "Age Determination for 346 Nearby Stars in the Herschel DEBRIS Survey", The Astronomical Journal, 143 (6): 135, arXiv:1203.1966Freely accessible, Bibcode:2012AJ....143..135V, doi:10.1088/0004-6256/143/6/135.
  9. ↑ "37 Gem -- Star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2016-09-12.
  10. ↑ http://www.cplire.ru/rus/ra&sr/VAK-2004.html (Russian)
  11. ↑ Williams, D.R. (2004). "Sun Fact Sheet". NASA. Retrieved 2009-06-23.
  12. ↑ 37 Geminorum at SIMBAD - Ids - Bibliography - Image.
  13. ↑ NASA, Science News, Solar Variability and Terrestrial Climate, Jan. 8, 2013
  14. ↑ University of Nebraska-Lincoln astronomy education group, Stellar Luminosity Calculator
  15. ↑ National Center for Atmospheric Research, The Effects of Solar Variability on Earth's Climate, 2012 Report
  16. ↑ Most of Earth’s twins aren’t identical, or even close!, by Ethan on June 5, 2013

External links

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