4 Ursae Minoris

4 Ursae Minoris
Observation data; Epoch J2000 Equinox J2000
Constellation	Ursa Minor
Right ascension	14h 08m 50.92654s
Declination	+77° 32′ 51.0466″
Apparent magnitude (V)	4.80
Characteristics
Spectral type	K3-IIIb Fe-0.5
B−V color index	1.368
Astrometry
Radial velocity (Rv)	+5.86±0.10 km/s
Proper motion (μ)	RA: −30.45 mas/yr ; Dec.: +32.85 mas/yr
Parallax (π)	7.14 ± 0.42 mas
Distance	460 ± 30 ly ; (140 ± 8 pc)
Absolute magnitude (MV)	−1.06
Orbit
Period (P)	605.8 d
Semi-major axis (a)	6.5 mas
Eccentricity (e)	0.137±0.012
Inclination (i)	136.0±5.1°
Longitude of the node (Ω)	325.5±2.8°
Periastron epoch (T)	2,438,901.7±8.5 JD
Argument of periastron (ω); (secondary)	311.8±5.2°
Semi-amplitude (K1); (primary)	12.65±0.16 km/s
Details
4 UMi A
Radius	28 R☉
Luminosity	436.72 L☉
Surface gravity (log g)	1.73±0.45 cgs
Temperature	4,165±48 K
Metallicity	−0.19±0.11 dex
Other designations
	4 UMi, BD+78° 478, FK5 524, HD 124547, HIP 69112, HR 5321, SAO 7958
Database references
SIMBAD	data

4 Ursae Minoris is a binary star^[6] system in the northern circumpolar constellation Ursa Minor. It is faintly visible to the naked eye with an apparent visual magnitude of 4.80.^[2] Based upon an annual parallax shift of 7.14±0.42 mas^[1] as seen from Earth's orbit, it is located roughly 460 light years from the Sun. It is moving further away with a heliocentric radial velocity of +5.9 km/s.^[5]

This is a single-lined spectroscopic binary star system with an orbital period of 1.66 years and an eccentricity of 0.14.^[7]^[6] The primary is a red giant of spectral type K3-IIIb Fe-0.5,^[3] a star that has used up its core hydrogen and is expanding. The suffix notation indicates the spectrum displays a mild underabundance of iron for a star of its type. It has expanded to around 28^[8] times the Sun's radius and is radiating 437^[2] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,165 K.^[9]

References

^ ^a ^b ^c ^d ^e ^f van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
^ ^a ^b ^c ^d Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
^ ^a ^b Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373.
^ ^a ^b Ryon, Jenna; et al. (August 2009), "Comparing the Ca ii H and K Emission Lines in Red Giant Stars", Publications of the Astronomical Society of the Pacific, 121 (882): 842, arXiv:0907.3346, Bibcode:2009PASP..121..842R, doi:10.1086/605456, S2CID 17821279.
^ ^a ^b De Bruijne, J. H. J.; Eilers, A.-C. (2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: A61, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347.
^ ^a ^b ^c Scarfe, C. D. (1971), "A Revised Orbit for 4 Ursae Minoris", Publications of the Astronomical Society of the Pacific, 83 (496): 807, Bibcode:1971PASP...83..807S, doi:10.1086/129218.
^ ^a ^b ^c Ren, Shulin; Fu, Yanning (March 2013), "Hipparcos Photocentric Orbits of 72 Single-lined Spectroscopic Binaries", The Astronomical Journal, 145 (3): 7, Bibcode:2013AJ....145...81R, doi:10.1088/0004-6256/145/3/81, S2CID 120199240, 81.
^ ^a ^b Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics, 367 (2) (Third ed.): 521–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451, S2CID 425754.
^ ^a ^b ^c ^d Koleva, M.; Vazdekis, A. (February 2012), "Stellar population models in the UV. I. Characterisation of the New Generation Stellar Library", Astronomy & Astrophysics, 538: 13, arXiv:1111.5449, Bibcode:2012A&A...538A.143K, doi:10.1051/0004-6361/201118065, S2CID 53999614, A143.
^ "4 UMi". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-04-02.

Zdroj:https://en.wikipedia.org?pojem=4_Ursae_Minoris
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[vanLeeuwen2007-1] ^ ^a ^b ^c ^d ^e ^f van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.

[Anderson2012-2] Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.

[Keenan1989-3] Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373.

[Ryon2009-4] Ryon, Jenna; et al. (August 2009), "Comparing the Ca ii H and K Emission Lines in Red Giant Stars", Publications of the Astronomical Society of the Pacific, 121 (882): 842, arXiv:0907.3346, Bibcode:2009PASP..121..842R, doi:10.1086/605456, S2CID 17821279.

[DeBruijne2012-5] De Bruijne, J. H. J.; Eilers, A.-C. (2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: A61, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347.

[Scarfe1971-6] Scarfe, C. D. (1971), "A Revised Orbit for 4 Ursae Minoris", Publications of the Astronomical Society of the Pacific, 83 (496): 807, Bibcode:1971PASP...83..807S, doi:10.1086/129218.

[Ren2013-7] Ren, Shulin; Fu, Yanning (March 2013), "Hipparcos Photocentric Orbits of 72 Single-lined Spectroscopic Binaries", The Astronomical Journal, 145 (3): 7, Bibcode:2013AJ....145...81R, doi:10.1088/0004-6256/145/3/81, S2CID 120199240, 81.

[cadars2001-8] Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics, 367 (2) (Third ed.): 521–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451, S2CID 425754.

[Koleva2012-9] Koleva, M.; Vazdekis, A. (February 2012), "Stellar population models in the UV. I. Characterisation of the New Generation Stellar Library", Astronomy & Astrophysics, 538: 13, arXiv:1111.5449, Bibcode:2012A&A...538A.143K, doi:10.1051/0004-6361/201118065, S2CID 53999614, A143.

[SIMBAD-10] "4 UMi". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-04-02.

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Observation data Epoch J2000 Equinox J2000
Constellation	Ursa Minor
Right ascension	14^h 08^m 50.92654^s^[1]
Declination	+77° 32′ 51.0466″^[1]
Apparent magnitude (V)	4.80^[2]
Characteristics
Spectral type	K3-IIIb Fe-0.5^[3]
B−V color index	1.368^[4]
Astrometry

Radial velocity (R_v)	+5.86±0.10^[5] km/s
Proper motion (μ)	RA: −30.45^[1] mas/yr Dec.: +32.85^[1] mas/yr
Parallax (π)	7.14 ± 0.42 mas^[1]
Distance	460 ± 30 ly (140 ± 8 pc)
Absolute magnitude (M_V)	−1.06^[4]

Orbit^[6]
Period (P)	605.8 d
Semi-major axis (a)	6.5 mas^[7]
Eccentricity (e)	0.137±0.012
Inclination (i)	136.0±5.1^[7]°
Longitude of the node (Ω)	325.5±2.8°
Periastron epoch (T)	2,438,901.7±8.5 JD
Argument of periastron (ω) (secondary)	311.8±5.2°
Semi-amplitude (K₁) (primary)	12.65±0.16 km/s
Details
4 UMi A
Radius	28^[8] `R`_☉
Luminosity	436.72^[2] `L`_☉
Surface gravity (log g)	1.73±0.45^[9] cgs
Temperature	4,165±48^[9] K
Metallicity	−0.19±0.11^[9] dex

Other designations
4 UMi, BD+78° 478, FK5 524, HD 124547, HIP 69112, HR 5321, SAO 7958^[10]
Database references
SIMBAD	data