R Ursae Minoris is a

star A star is a luminous spheroid of plasma (physics), plasma held together by Self-gravitation, self-gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night sk ...

in the

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The first constellati ...

Ursa Minor Ursa Minor (, contrasting with Ursa Major), also known as the Little Bear, is a constellation located in the far northern celestial hemisphere, northern sky. As with the Great Bear, the tail of the Little Bear may also be seen as the handle of ...

. A red giant of spectral type M7IIIe, it is a semiregular variable ranging from magnitude 8.5 to 11.5 over a period of 325 days. In 1881,

Edward Charles Pickering Edward Charles Pickering (July 19, 1846 – February 3, 1919) was an American astronomer and physicist and the older brother of William Henry Pickering. Along with Carl Vogel, Pickering discovered the first spectroscopic binary stars. He wrote ' ...

announced that the star, at that time unnamed, is a

variable star A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes systematically with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are ...

. It was listed with its

variable star designation In astronomy, a variable-star designation is a unique identifier given to variable stars. It extends the Bayer designation format, with an identifying label (as described below) preceding the Latin genitive of the name of the constellation in whic ...

, R Ursae Minoris, in Annie Jump Cannon's 1907 work ''Second Catalog of Variable Stars''.

References

Ursa Minor M-type giants Semiregular variable stars Ursae Minoris, R Emission-line stars Durchmusterung objects 149683 080802 {{giant-star-stub