Astronomy:T Leporis

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Short description: Star in the constellation Lepus
T Leporis
T Leporis.jpg
T Leporis (below) compared to the Sun and Earth's orbit (above)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Lepus
Right ascension  05h 04m 50.85s[1]
Declination −21° 54′ 16.5″[1]
Apparent magnitude (V) 7.4 - 14.3[2]
Characteristics
Spectral type M6e-M9e[2]
Variable type Mira[2]
Astrometry
Radial velocity (Rv)−4[3] km/s
Parallax (π)2.9585 ± 0.1889[1] mas
Distance1,100 ± 70 ly
(340 ± 20 pc)
Details
Mass2.7[4] M
Surface gravity (log g)−0.5[4] cgs
Temperature2,800[4] K
Other designations
Database references
SIMBADdata

T Leporis (T Lep / HD 32803 / HIP 23636) is a variable star in the constellation of Lepus, the Hare. It is located half a degree from ε Leporis in the sky; its distance is approximately 1,100 light years from the Solar System. It has the spectral type M6ev, and is a Mira variable — as is R Leporis, in the same constellation — whose apparent magnitude varies between +7.40 and +14.30 with a period of 368.13 days.[2]

The annual parallax of T Leporis was measured by the Hipparcos mission, but the results were hopelessly imprecise.[5] The parallax from Gaia Data Release 2 is more accurate and yields a distance of 340±20 pc.[1] The distance has also been measured using very-long-baseline interferometry and found to be 327±4 pc.[6]

The visual band light curve of T Leporis, from AAVSO data[7]

Mira variables are some of the major sources of molecules and dust in the Universe. With each pulsation, T Leporis expels matter into space, each year losing an amount equivalent to the mass of Earth. Images of T Leporis obtained with the Very Large Telescope interferometer of the European Southern Observatory (ESO) have revealed a shell of gas and dust surrounding the star, whose diameter is some 100 times larger than that of the Sun.[8] Given the great distance at which this class of stars lie, its apparent angular diameter — despite its enormous size — is no more than a millionth of the solar apparent angular diameter.

See also

  • Mira Ceti

References

  1. 1.0 1.1 1.2 1.3 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  2. 2.0 2.1 2.2 2.3 Samus, N. N. et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S 1: B/gcvs. Bibcode2009yCat....102025S. 
  3. Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters 32 (11): 759–771. doi:10.1134/S1063773706110065. Bibcode2006AstL...32..759G. 
  4. 4.0 4.1 4.2 Pérez-Mesa, V.; Zamora, O.; García-Hernández, D. A.; Plez, B.; Manchado, A.; Karakas, A. I.; Lugaro, M. (2017). "Rubidium and zirconium abundances in massive Galactic asymptotic giant branch stars revisited". Astronomy and Astrophysics 606: A20. doi:10.1051/0004-6361/201731245. Bibcode2017A&A...606A..20P. 
  5. Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode2007A&A...474..653V. 
  6. Nakagawa, Akiharu; Omodaka, Toshihiro; Handa, Toshihiro; Honma, Mareki; Kawaguchi, Noriyuki; Kobayashi, Hideyuki; Oyama, Tomoaki; Sato, Katsuhisa et al. (2014). "VLBI astrometry of AGB variables with VERA: A Mira-type variable T Lepus". Publications of the Astronomical Society of Japan 66 (6): 101. doi:10.1093/pasj/psu103. Bibcode2014PASJ...66..101N. 
  7. "Download Data". AAVSO. https://www.aavso.org/data-download. 
  8. "Unique Details Of Double Star In Orion Nebula And Star T Leporis Captured By 'Virtual' Telescope". 19 February 2009. http://www.sciencedaily.com/releases/2009/02/090218103517.htm.