Astronomy:Stella Ludoviciana
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| 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 | |
| Evolutionary stage | main sequence[1] |
| Spectral type | A5-F0[3][4] |
| Astrometry | |
| Radial velocity (Rv) | −3.42±0.35[1] 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 |
| Distance | 297.5 ± 0.8 ly (91.2 ± 0.2 pc) |
| Details | |
| Mass | 1.5[1] M☉ |
| Radius | 1.6[1] R☉ |
| Luminosity | 6.2[1] L☉ |
| Surface gravity (log g) | 4.13[1] cgs |
| Temperature | 7,223[1] K |
| Age | 961[1] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
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Stella Ludoviciana, also known as HD 116798,[6] is an 8th-magnitude star in the asterism of the Big Dipper in the constellation Ursa Major, halfway between Mizar and Alcor. 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 was observed on 2 December 1722 by Johann Georg Liebknecht, who mistook it for a planet and named it after Louis V, Landgrave of Hesse-Darmstadt. Unknown to Liebknecht, it had been previously observed by Benedetto Castelli in 1616.[7]: 257 In different sources the name may be written as "Sidus Ludovicianum",[8] "Sidus Ludoviciana",[6] or "Stella Ludoviciana".[7]: 257 The name Stella Ludoviciana was officially approved by the IAU Working Group on Star Names on 17 April 2026.[9]
The star is six times more luminous than the Sun, 1.6 times its radius, and has a surface temperature of 7,200 K.[1] 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 Stella Ludoviciana.[1] It shows evidence of Gamma Doradus pulsations, and is a likely member of a young stellar association known as Group-X.[10]
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 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.
- ↑ 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. Bibcode: 2000A&A...355L..27H.
- ↑ Henry Draper Catalogue and Extension, A. J. Cannon and E. C. Pickering, CDS ID III/135A.
- ↑ 4.0 4.1 4.2 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. Bibcode: 1999A&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.
- ↑ "HD 116798". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+116798.
- ↑ 6.0 6.1 6.2 "The Big Dipper Adds a Star" (in en-US). 2009-12-11. https://skyandtelescope.org/astronomy-news/the-big-dipper-adds-a-star/.
- ↑ 7.0 7.1 Siebert, Harald (August 2005). "The early search for stellar parallax: Galileo, Castelli, and Ramponi". Journal for the History of Astronomy 36 (3): 251–271. doi:10.1177/002182860503600301. Bibcode: 2005JHA....36..251S. https://articles.adsabs.harvard.edu/pdf/2005JHA....36..251S.
- ↑ Allen, R. H. (1899). Star Names: Their Lore and Meaning. p. 446. https://penelope.uchicago.edu/Thayer/E/Gazetteer/Topics/astronomy/_Texts/secondary/ALLSTA/Ursa_Major*.html.
- ↑ "IAU Catalog of Star Names". https://exopla.net/star-names/modern-iau-star-names/.
- ↑ Newton, Elisabeth R. et al. (September 2022). "TESS Hunt for Young and Maturing Exoplanets (THYME). VII. Membership, Rotation, and Lithium in the Young Cluster Group-X and a New Young Exoplanet". The Astronomical Journal 164 (3): 115. doi:10.3847/1538-3881/ac8154. Bibcode: 2022AJ....164..115N.
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