Kappa Ursae Majoris (κ UMa / κ Ursae Majoris) is a binary star in the constellation Ursa Major. It is approximately 423 light years from Earth and has the traditional names Talitha Australis, Al Kaprah, and Alphikra Australis.
Both components of the binary star are a white A-type main sequence dwarfs. They have apparent magnitudes of +4.2 and +4.4, which gives the system a combined apparent magnitude of +3.57. The orbital period of the binary is 36 or 74 years, and the two stars are separated by 0.13 arcseconds.
Both components of the binary star are a white A-type main sequence dwarfs. They have apparent magnitudes of +4.2 and +4.4, which gives the system a combined apparent magnitude of +3.57. The orbital period of the binary is 36 or 74 years, and the two stars are separated by 0.13 arcseconds.
Chi Ursae Majoris (χ UMa / χ Ursae Majoris) is a star in the constellation Ursa Major. It also has the traditional names Alkafzah, Alkaphrah, and El Koprah.
Chi Ursae Majoris is an orange K-type giant with an apparent magnitude of +3.69. It is approximately 196 light years from Earth.
The Spiral Galaxy NGC 3877 (= H I.201), type Sc, in Ursa Major is best found from the 3.7-mag star Chi Ursae Majoris, which is almost exactly 15 arc minutes north of the galaxy.
Chi Ursae Majoris is an orange K-type giant with an apparent magnitude of +3.69. It is approximately 196 light years from Earth.
The Spiral Galaxy NGC 3877 (= H I.201), type Sc, in Ursa Major is best found from the 3.7-mag star Chi Ursae Majoris, which is almost exactly 15 arc minutes north of the galaxy.
Upsilon Ursae Majoris (υ UMa / υ Ursae Majoris) is a binary star in the constellation Ursa Major. It is approximately 115 light years from Earth.
The primary component, Upsilon Ursae Majoris A, is a yellow-white F-type subgiant with a mean apparent magnitude of +3.78. It is classified as a Delta Scuti type variable star and its brightness varies from magnitude +3.68 to +3.86 with a period of 3.18 hours. The companion, Upsilon Ursae Majoris B is a magnitude +11.5 star, 11.3 arcseconds away from the primary.
The primary component, Upsilon Ursae Majoris A, is a yellow-white F-type subgiant with a mean apparent magnitude of +3.78. It is classified as a Delta Scuti type variable star and its brightness varies from magnitude +3.68 to +3.86 with a period of 3.18 hours. The companion, Upsilon Ursae Majoris B is a magnitude +11.5 star, 11.3 arcseconds away from the primary.
Xi Ursae Majoris (ξ UMa / ξ Ursae Majoris) is a star system in the constellation Ursa Major. It also has the traditional name Alula Australis (The word Alula comes from an Arabic phrase meaning ‘first leap’; the distinctions ‘northern’ (Borealis) and ‘southern’ (Australis) are added in Latin).
On May 2, 1780, Sir William Herschel discovered that this was a binary star system, making it the first such system ever discovered. It was the first visual double star for which an orbit was calculated, when it was computed by Félix Savary in 1828.
The system is composed of a double star whose two components are yellow G-type main sequence dwarfs. The brighter component, Xi Ursae Majoris A, has a mean apparent magnitude of +4.41. It is classified as an RS Canum Venaticorum type variable star and its brightness varies by 0.01 magnitudes. The companion star, Xi Ursae Majoris B has an apparent magnitude of +4.87. The orbital period of the two stars is 59.84 years, and they are currently separated by 1.2 arcseconds, or at least 10 Astronomical Units.
Each component of this double star is itself a spectroscopic binary. B's binary companion, denoted Xi Ursae Majoris Bb, is unresolved, but the binary star is known to have an orbital period of 3.98 days.
On May 2, 1780, Sir William Herschel discovered that this was a binary star system, making it the first such system ever discovered. It was the first visual double star for which an orbit was calculated, when it was computed by Félix Savary in 1828.
The system is composed of a double star whose two components are yellow G-type main sequence dwarfs. The brighter component, Xi Ursae Majoris A, has a mean apparent magnitude of +4.41. It is classified as an RS Canum Venaticorum type variable star and its brightness varies by 0.01 magnitudes. The companion star, Xi Ursae Majoris B has an apparent magnitude of +4.87. The orbital period of the two stars is 59.84 years, and they are currently separated by 1.2 arcseconds, or at least 10 Astronomical Units.
Each component of this double star is itself a spectroscopic binary. B's binary companion, denoted Xi Ursae Majoris Bb, is unresolved, but the binary star is known to have an orbital period of 3.98 days.
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