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Proper NameNone
Bayer DesignationNone
Flamsteed Number36 Ursae Majoris
HR (BSC)4112
ConstellationUrsa Major
Right Ascension10h 30m 38s
Declination+55° 58' 50"
Distance42 light years
13 parsecs
MagnitudeApparent: +4.8
Absolute: +4.3
Spectral ClassF8V bright yellow dwarf
Optimum VisibilityMarch (Usually visible from northern latitudes)

A fifth magnitude star in Ursa Major, a little to the west of the 'blade' of the Plough (or the 'bowl' of the Big Dipper). 36 Ursae Majoris is a faint neighbour to the much more prominent Merak, the southern of the two Pointer stars and the southwestern star of the Plough. Though 36 Ursae Majoris is much fainter in the sky than Merak, it is only about half as far from Earth (Merak is intrinsically much more luminous than its neighbour, and so appears noticeably brighter despite its greater distance).

Visible in the northeastern (top left) corner of this image of 36 Ursae Majoris is the faint form of the spiral galaxy NGC 3264. Imagery provided by Aladin sky atlas

36 Ursae Majoris is a relatively Sun-like star, though a little larger and more massive than the Sun itself. It is also about 6% hotter than the Sun, with a surface temperature of about 6,100 K. This higher temperature gives it a whiter colouration, placing it in the F-type bright yellow classification (as opposed to the Sun's G-type yellow spectral class).

This star is probably a triple system, with two other lower-mass stars that appear to follow its relatively rapid proper motion, and are therefore likely to be gravitationally bound to the system's primary star. This main star has a circumstellar disc orbiting far from the star itself, at a distance of some 39 AU (that is, rather farther from 36 Ursae Majoris than Neptune is from the Sun). Variations in the star's spectrum imply that it may also have other bodies in orbit - probably giant planets or perhaps brown dwarfs - though the existence of these bodies has not yet been conclusively demonstrated.


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