Astronomy:Sidus Ludoviciana

From HandWiki
Short description: Star in the constellation Ursa Major
Sidus Ludoviciana
Mizar, Alcor and Sidus Ludoviciana.jpg
Red circle.svg
Location of Sidus Ludoviciana (circled)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Ursa Major
Right ascension  13h 24m 51.8521s[1]
Declination +54° 53′ 50.841″[1]
Apparent magnitude (V) +7.58[2]
Characteristics
Spectral type A5-F0[3][4]
Astrometry
Radial velocity (Rv)−4.9[4] km/s
Proper motion (μ) RA: −20.171[1] mas/yr
Dec.: −5.330[1] mas/yr
Parallax (π)10.9650 ± 0.0281[1] mas
Distance297.5 ± 0.8 ly
(91.2 ± 0.2 pc)
Details
Mass1.5[1] M
Radius1.6[1] R
Luminosity6.2[1] L
Surface gravity (log g)4.13[1] cgs
Temperature7,223[1] K
Age961[1] Myr
Other designations
Sidus Ludoviciana, HD 116798, SAO 28748, BD+55°1602, GC 18150, TYC 3850-257-1, 2MASS J13245185+5453509
Database references
SIMBADdata
Sidus Ludoviciana between the brighter Mizar and Alcor (north is towards the right)

Sidus Ludoviciana /ˈsdəs ˌljdˌvɪsiˈnə/[citation needed], also known as HD 116798[5] is an 8th-magnitude giant star in the asterism of the Big Dipper in the constellation Ursa Major, halfway between Mizar and Alcor. It was discovered on 2 December 1722 by Johann Georg Liebknecht, who mistook it for a planet and named it after Louis V, Landgrave of Hesse-Darmstadt. A line-of-sight companion with Mizar and Alcor (with a spectral type similar to the latter), it is roughly four times more distant. It has the spectral type A8/F0 III.[4] That spectral class suggests it is a giant star, but evolutionary models place it on the main sequence.[1]

The star is six times more luminous than the Sun, 1.6 times its radius, and has a surface temperature of 7,200 K. Spectral classification based on a spectrum taken for radial velocity measurement tentatively determined a spectral and luminosity class of A8/F0III,[4] which would indicate that it has exhausted its core hydrogen and started to evolve away from the main sequence, however giant stars of this type should be at least ten times more luminous than measured for Sidus Ludoviciana.

References

  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  2. Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P. et al. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics 355: L27. Bibcode2000A&A...355L..27H. 
  3. Henry Draper Catalogue and Extension, A. J. Cannon and E. C. Pickering, CDS ID III/135A.
  4. 4.0 4.1 4.2 4.3 Grenier, S.; Baylac, M.-O.; Rolland, L.; Burnage, R.; Arenou, F.; Briot, D.; Delmas, F.; Duflot, M. et al. (1999). "Radial velocities. Measurements of 2800 B2-F5 stars for HIPPARCOS". Astronomy and Astrophysics Supplement 137 (3): 451. doi:10.1051/aas:1999489. Bibcode1999A&AS..137..451G. https://hal.archives-ouvertes.fr/hal-02053966/file/Grenier%20et%20al.%20-%201999%20-%20Radial%20velocities.%20Measurements%20of%202800%20B2-F5%20star.pdf. 
  5. "The Big Dipper Adds a Star" (in en-US). 2009-12-11. https://skyandtelescope.org/astronomy-news/the-big-dipper-adds-a-star/. 

External links