Ursa Minor, also known as the Little Bear, is a constellation located in the far northern sky. As with the Great Bear, the tail of the Little Bear may also be seen as the handle of a ladle, hence the North American name, Little Dipper: seven stars with four in its bowl like its partner the Big Dipper. Ursa Minor was one of the 48 constellations listed by the 2nd-century astronomer Ptolemy, and remains one of the 88 modern constellations. Ursa Minor has traditionally been important for navigation, particularly by mariners, because of Polaris being the north pole star.
Kochab, Bayer designation Beta Ursae Minoris, is the brightest star in the bowl of the Little Dipper asterism, and only slightly fainter than Polaris, the northern pole star and brightest star in Ursa Minor. Kochab is 16 degrees from Polaris and has an apparent visual magnitude of 2.08. The distance to this star from the Sun can be deduced from the parallax measurements made during the Hipparcos mission, yielding a value of 130.9 light-years.
Pollux is the brightest star in the constellation of Gemini. It has the Bayer designation β Geminorum, which is Latinised to Beta Geminorum and abbreviated Beta Gem or β Gem. This is an orange-hued, evolved red giant located at a distance of 34 light-years, making it the closest red giant to the Sun. Since 1943, the spectrum of this star has served as one of the stable anchor points by which other stars are classified. In 2006 an exoplanet was announced to be orbiting it.
47 Ursae Majoris, formally named Chalawan, is a yellow dwarf star approximately 45.3 light-years from Earth in the constellation of Ursa Major. As of 2011, three extrasolar planets are believed to orbit the star.
Beta Cancri, also named Tarf, is the brightest star in the zodiacal constellation of Cancer. It has an apparent visual magnitude of +3.5 and an absolute magnitude of −1.2. Based on parallax measurements obtained during the Hipparcos mission, it is approximately 290 light-years distant from the Sun. An exoplanet, designated Beta Cancri b, is believed to be orbiting the star.
Mu Leonis, also named Rasalas, is a star in the constellation of Leo. The apparent visual magnitude of this star is 3.88, which is bright enough to be seen with the naked eye. Based upon an annual parallax shift of 0.02628 arc seconds as measured by the Hipparcos satellite, this system is 124 light-years from the Sun. In 2014, an exoplanet was discovered to be orbiting the star.
Zeta Ursae Minoris, which is Latinized from ζ Ursae Minoris, is a single star in the northern circumpolar constellation of Ursa Minor, forming the northernmost part of the bowl in this "little dipper" asterism. The star has a white hue and is faintly visible to the naked eye with an apparent visual magnitude of +4.28. It is located at a distance of approximately 369 light-years from the Sun based on parallax, but is drifting further closer with a radial velocity of about –13 km/s.
HD 66141 is a single star in the equatorial constellation of Canis Minor. It has the Bayer designation G Canis Minoris, the Gould designation 50 G. Canis Minoris, and has the HR 3145 identifier from the Bright Star Catalogue. When first catalogued it was in the Puppis constellation and was designated "13 Puppis", but it subsequently migrated to Canis Minor. Bode gave it the Bayer designation of Lambda Canis Minoris.
55 Cancri b, occasionally designated 55 Cancri Ab, also named Galileo, is an exoplanet orbiting the Sun-like star 55 Cancri A every 14.65 days. It is the second planet in order of distance from its star, and is an example of a hot Jupiter, or possibly rather "warm Jupiter".
55 Cancri c, formally named Brahe, is an extrasolar planet in an eccentric orbit around the Sun-like star 55 Cancri A, making one revolution every 44.34 days. It is the third known planet in order of distance from its star. 55 Cancri c was discovered on June 13, 2002, and has a mass roughly half of Saturn.
55 Cancri d, formally named Lipperhey, is an extrasolar planet in a long-period orbit around the Sun-like star 55 Cancri A. Located at a similar distance from its star as Jupiter is from the Sun, it is the fifth and outermost known planet in its planetary system. 55 Cancri d was discovered on June 13, 2002.
Pollux b, formally named Thestias, is an exoplanet candidate orbiting the star Pollux approximately 34 light-years away in the constellation of Gemini. It is also designated β Geminorum b or HD 62509 b. If this planet exists, it has a minimum mass of about twice the mass of Jupiter, and it moves around Pollux in 1.61 years at a distance of 1.64 AU in a nearly circular orbit. However, its existence has been disputed.
47 Ursae Majoris b, formally named Taphao Thong, is a gas planet and an extrasolar planet approximately 46 light-years from Earth in the constellation of Ursa Major. The planet was discovered located in a long-period orbit around the star 47 Ursae Majoris in January 1996 and as of 2011 it is the innermost of three known planets in its planetary system. It has a mass at least 2.53 times that of Jupiter.
39 Cygni is a binary star system near the southern border of the northern constellation of Cygnus, approximately 270 light years away from Earth. It is visible to the naked eye as an orange-hued star with an apparent visual magnitude of 4.43. The system is moving closer to the Sun with a heliocentric radial velocity of −15 km/s.
Aldebaran b is a candidate exoplanet orbiting the orange giant star Aldebaran, 65 light-years away. It was initially detected in 1993, but was considered doubtful until 2015, when researchers came to a conclusion that there is likely an exoplanet orbiting Aldebaran, consistent with the original calculations, but also compatible with stellar activity. However, in 2019, new data placed doubts on its existence again.
Beta Leonis Minoris, Latinized from β Leonis Minoris, is a binary star in the constellation of Leo Minor. It has an overall apparent visual magnitude of approximately 4.2. Although it is the only star in Leo Minor with a Bayer designation, it is only the second brightest star in the constellation.
HD 32518 is a star with an orbiting exoplanet in the northern circumpolar constellation Camelopardalis. It has an apparent magnitude of 6.42, placing it near the limit of naked eye visibility. Located 397 light years away based on parallax measurements, it is receding with a heliocentric radial velocity of −7.02 km/s.
11 Ursae Minoris is a single star located approximately 410 light years away in the northern circumpolar constellation of Ursa Minor. The star is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 5.15. It is moving closer to the Earth with a heliocentric radial velocity of −17.8 km/s.
11 Ursae Minoris b is an extrasolar planet which orbits the K-type giant star 11 Ursae Minoris, located approximately 390 light years away in the constellation Ursa Minor. This planet has a minimum mass of 10.5 MJ. Since inclination is not known, the actual mass is unknown. This planet may actually be a brown dwarf if a true mass is over 13 times that of Jupiter. This planet takes 17 months to orbit the star at the average distance of 1.54 AU in a circular orbit. This superjovian planet was detected by radial velocity method on August 12, 2009.
Beta Pictoris c is the second exoplanet discovered orbiting the young star Beta Pictoris, located approximately 63 light-years away from Earth in the constellation of Pictor. Its mass is around nine times that of Jupiter, and it orbits at around 2.7 astronomical units (AU) from Beta Pictoris, about 3.5 times closer to its parent star than Beta Pictoris b. It has an orbital period of 1,200 days. The orbit of Beta Pictoris c is moderately eccentric, with an eccentricity of 0.24.
