SkyEye: Ursa Major

The Greater Bear

Abbreviation:	UMa
Genitive:	Ursae Majoris
Origin:	[antiquity]
Fully Visible:	16°S – 90°N

Interestingly, this constellation is known as a bear in many diverse civilisations. In Greek mythology, Zeus, the king of the gods, lusts after the beautiful nymph Callisto. Hera, Zeus's long-suffering wife, isn't best pleased and turns Callisto into a bear. Callisto, in ursine form, comes across her son Arcas who nearly shoots her but Zeus averts tragedy by turning them both into bears and placing them in the sky. Callisto is the greater bear and Arcas the lesser.

The most striking part of the constellation is the asterism of seven stars known as 'The Big Dipper' in North America and 'The Plough' in the British Isles. It is the 'Northern Ladle' in many Asian cultures and a wagon or cart in northern Europe. Five of the seven stars are thought to have a common origin and are moving through space together. They are called the Ursa Major Moving Group. Dubhe and Alkaid are not members of the group.

The obsolete constellation Jordanus Fluvius (the Jordan River) flows around the great bear on some old star atlases.

The constellation of Ursa Major

Notable Features

Visible Named Stars
α UMa	Dubhe	This is a member of the asterism called 'The Big Dipper' or 'The Plough'. With Merak, it is one of the 'Pointers to the Pole'. In Chinese astronomy, this star is known as Tianshu, from Tiān Shū meaning 'the celestial pivot'.
β UMa	Merak	This is a member of the asterism called 'The Big Dipper' or 'The Plough'. With Dubhe, it is one of the 'Pointers to the Pole'. In Chinese astronomy, this star is known as Tianxuan, from Tiān Xuán meaning 'the celestial rotating jade'.
γ UMa	Phecda	This is a member of the asterism called 'The Big Dipper' or 'The Plough'. It sometimes appears as Phad in older star atlases and catalogues. In Chinese astronomy, this star is known as Tianji, from Tiān Jī meaning 'the celestial shining pearl'.
δ UMa	Megrez	This is a member of the asterism called 'The Big Dipper' or 'The Plough'. It appears as Kaffa in Antonín Bečvář's Atlas of the Heavens — Ⅱ Catalogue 1950.0. The derivation of the name is unknown. In Chinese astronomy, this star is known as Tianquan, from Tiān Quán meaning 'the celestial balance'.
ε UMa	Alioth	This is a member of the asterism called 'The Big Dipper' or 'The Plough'. In Chinese astronomy, this star is known as Yuheng, from Yù Héng meaning 'the jade sighting-tube'.
ζ UMa	Mizar	This is a member of the asterism called 'The Big Dipper' or 'The Plough'. It was the first telescopic binary to be discovered. As it turns out, each component of the binary star is also binary, discovered through spectroscopy. Four stars for the price of one! This star sometimes appears as Al Anaq (from the Arabic al‑ʿanāq meaning 'the female kid') in older star atlases and catalogues. In Chinese astronomy, this star is known as Kaiyang, from Kāi Yáng meaning 'the opener of heat'.
η UMa	Alkaid	This is a member of the asterism called 'The Big Dipper' or 'The Plough'. It sometimes appears as Benetnasch (from the Arabic banāt naʿsh al‑kubrā meaning 'the daughters of the bier') in older star atlases and catalogues. In Chinese astronomy, this star is known as Yaoguang, from Yáo Guāng meaning 'the twinkling brilliance'.
ι UMa	Talitha	This was one of three navigational stars jokingly renamed by NASA astronaut 'Gus' Grissom. Known as Dnoces, it is the word 'second' spelled backwards in honour of Apollo 1 astronaut Edward Higgins White Ⅱ.
κ UMa	Alkaphrah	In Chinese astronomy, ι UMa and κ UMa together are known as Shangtai, from Shàng Tái meaning 'the upper step'.
λ UMa	Tania Borealis	In Chinese astronomy, λ UMa and μ UMa together are known as Zhongtai, from Zhōng Tái meaning 'the middle step'.
μ UMa	Tania Australis	This third-magnitude star is a spectroscopic binary.
ν UMa	Alula Borealis	In Chinese astronomy, ν UMa and ξ UMa together are known as Xiatai, from Xià Tái meaning 'the lower step'.
ξ UMa	Alula Australis	This star is classified as an RS CVn-type variable but its brightness varies only by a miniscule 0.01 magnitude.
χ UMa	Taiyangshou	The name of this star, from Chinese astronomical tradition, was officially adopted by the IAU in 2017.
ο UMa	Muscida	This high-proper motion star shines at third magnitude.
47 UMa	Chalawan	This fifth-magnitude star is known to have at least two exoplanets.
80 UMa	Alcor	Alcor is a faint companion of Mizar and anyone with normal eyesight and dark skies should be able to see. Alcor is actually a binary star and is gravitationally bound to its companion Mizar, making this a six-star system! This star sometimes appears as Al Suha (from the Arabic al‑suhā meaning 'the overlooked one') in older star atlases and catalogues. In Chinese astronomy, this star is known as Fu, from Fŭ meaning 'the assistant'.
41 Lyn	Intercrus	This fifth-magnitude star is known to have at least one exoplanet. This star was originally part of the constellation of Lynx, hence its Flamsteed designation. However, when the official constellation boundaries were drawn in the early twentieth century, Intercrus ended up within Ursa Major.
Other Interesting Stars
GJ 411		At just over 8 light years distant, this star is one of the closest stars to the Sun, but it is just a little too faint to be seen with the naked eye.
HAT‑P‑3	Dombay	This twelfth-magnitude star is known to have at least one exoplanet. It is located just south of Alkaid (η UMa).
HAT‑P‑21	Mazaalai	This eleventh-magnitude star is known to have at least one exoplanet.
HD 68988	Násti	Found just north of Muscida (ο UMa), this eighth-magnitude star is known to have at least one exoplanet.
HD 102956	Aniara	This eighth-magnitude star is known to have at least one exoplanet. It appears within the 'bowl' of the 'dipper'.
HD 118203	Liesma	This eighth-magnitude star is known to have at least one exoplanet. It is in the vicinity of Mizar (ζ UMa).
Deep Sky Objects
M40		This is actually the binary star Winnecke 4 and thus, is an unusual object to be accorded a Messier designation.
M81	Bode's Galaxy	This spiral galaxy is bright and easy to see in a small telescope, making it a popular target for amateurs.
M82	Cigar Galaxy	Nearby is this irregular galaxy, the prototype starburst galaxy.
M97	Owl Nebula	This planetary nebula has been known by this name since 1848 when the Third Earl of Rosse drew a picture of it which was said to resemble an owl.
M101	Pinwheel Galaxy	This face-on spiral galaxy is a good telescopic target if the sky is very dark. It is thought to be 70% larger than the Milky Way.
M108		A telescope is necessary to view this barred spiral galaxy.
M109		Another barred spiral galaxy, this one is known to have at least three companion galaxies.