R Microscopii

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R Microscopii
RMicLightCurve.png
The visual band light curve of R Microscopii, from AAVSO data [1]
Observation data
Epoch J2000.0        Equinox J2000.0 (ICRS)
Constellation Microscopium
Right ascension 20h 40m 02.98684s . [2]
Declination 28° 47 31.1983 [2]
Apparent magnitude  (V)8.3-13.8
Characteristics
Spectral type M4e [3]
Astrometry
Parallax (π)1.2239 ± 0.1089 [4]   mas
Distance 2,700 ± 200  ly
(820 ± 70  pc)
Other designations
R  Microscopii, HD  196717, HIP  101985, CD–29° 17235
Database references
SIMBAD data

R Microscopii is a star in the constellation Microscopium. It is a red giant star of spectral type M4e that is also a Mira variable, with an apparent magnitude ranging between 8.3 and 13.8 over 138 days. [3] Located around 1000 light-years distant, it shines with a luminosity 444 times that of the Sun and has a surface temperature of 3141 K. [5] The Astronomical Society of Southern Africa in 2003 reported that observations of R Microscopii were urgently needed as data on its light curve was incomplete. [6]

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AV Microscopii is a variable star in the southern constellation of Microscopium. It is a dim, red-hued star near the lower limit of visibility to the naked eye with a baseline apparent visual magnitude of 6.28. The star is located approximately 740 light years away from the Sun, based on parallax, but is moving closer with a radial velocity of −23 km/s. It is a member of the Milky Way's old disk population.

S Microscopii Variable star in the constellation Microscopium

S Microscopii is a star in the constellation Microscopium. It is a red giant star of spectral type M3e-M5.5 that is also a Mira variable, with an apparent magnitude ranging between 7.4 and 14.8 over 210 days. The Astronomical Society of Southern Africa in 2003 reported that observations of S Microscopii were very urgently needed as data on its light curve was incomplete.

U Microscopii Variable star in the constellation Microscopium

U Microscopii is a Mira variable star in the constellation Microscopium. It ranges from magnitude 7 to 14.4 over a period of 334 days. The Astronomical Society of Southern Africa in 2003 reported that observations of U Microscopii were very urgently needed as data on its light curve was incomplete.

T Microscopii is a semiregular variable star in the constellation Microscopium. It ranges from magnitude 6.74 to 8.11 over a period of 352 days. Located around 700 light-years distant, it shines with a bolometric luminosity 7,509 times that of the Sun and has a surface temperature of 2,750 K.

1 Lyncis is a single star in the northern constellation of Lynx. It is also known by its variable star designation of UW Lyncis; 1 Lyncis is the Flamsteed designation. This object is visible to the naked eye as a faint, reddish-hued star with an apparent visual magnitude of 4.95. It is moving further from the Earth with a heliocentric radial velocity of 12 km/s.

DU Lyncis is a single variable star in the constellation Lynx. It is a faint star but visible to the naked eye with an apparent visual magnitude of 5.15. With an annual parallax shift of 9.2 mas, it is located some 350 light years from the Sun. The star is moving closer with a heliocentric radial velocity of −37 km/s.

R Octantis Variable star in the constellation Octans

R Octantis is a Mira variable star located in the southern constellation of Octans. It shines with a luminosity 9304 times that of the Sun and has a surface temperature of 2571 K.

References

  1. "Download Data". aavso.org. AAVSO. Retrieved 1 October 2021.
  2. 1 2 SIMBAD, R Microscopii (accessed 20 March 2015)
  3. 1 2 Watson, Christopher (4 January 2010). "R Microscopii". AAVSO Website. American Association of Variable Star Observers . Retrieved 20 March 2015.
  4. Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics . 616. A1. arXiv: 1804.09365 . Bibcode: 2018A&A...616A...1G . doi: 10.1051/0004-6361/201833051 . Gaia DR2 record for this source at VizieR.
  5. McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (2012). "Fundamental Parameters and Infrared Excesses of Hipparcos Stars". Monthly Notices of the Royal Astronomical Society. 427 (1): 343–57. arXiv: 1208.2037 . Bibcode:2012MNRAS.427..343M. doi:10.1111/j.1365-2966.2012.21873.x. S2CID   118665352.
  6. Cooper, Tim (2003). "Presidential address: Amateur Observations - Successes and Opportunities". Monthly Notes of the Astronomical Society of Southern Africa. 62: 234–40. Bibcode:2003MNSSA..62..234C.