The constellation also has a total of four stars with confirmed planets. Ursa Minor also contains Earth’s nearest neutron star called Calvera located just 250 light years away as well as the hottest white dwarf yet discovered, H1504+65, which burns at a fiery 200,000 K. It has 15 times the Sun’s radius, is 1,100 times more luminous, and has a rotational velocity of around 180 km/s. – Pherkad (Gamma Ursae Minoris), the constellation’s third brightest star, is a blue giant (A3 lab) situated 487 light years from our solar system of magnitude 3.05. Together, the stars Pherkad and Kochab are known as the “guardians of the pole star”. It has 2.2 times our sun’s mass, and 130 times brighter. – Kochab (Beta Ursae Minoris), the second brightest star in Ursa Minor, is an orange giant (K4 III) situated 132 light years from the Sun that shines with a magnitude of 2.08. It is located 434 light years from our solar system, but is actually a triple star system consisting of the supergiant Polaris A, and two smaller yellow-white dwarf companions called Polaris Ab and Polaris B. Polaris is useful for determining the direction of north, as it is aligned almost perfectly with the North Celestial Pole, being offset by just 0.7 degrees. – Polaris ( Alpha Ursae Minoris) is located at the end of the Little Dipper’s handle, with this yellow supergiant (F7:Ib-II) easily spotted as it has an apparent visual magnitude of 1.97. In some Greek accounts, Ursa Minor is sometimes referred to as “The Phoenician”, which seems to lend some credence to the story. The Phoenicians were accomplished navigators, and Ursa Minor is an excellent pointer to true north due to its close proximity to the North Celestial Pole. However, a dissenting school of thought holds that Thales only introduced the constellation to the Greeks, and that his knowledge of it derives from being of Phoenician descent. Ursa Minor belongs to the Ursa Major family of constellations, along with Coma Berenices, Boötes, Camelopardalis, Canes Venatici, Corona Borealis, Draco, Leo Minor, Ursa Major and Lynx.Įxactly how Ursa Minor came about as a constellation is not clear, but it is widely thought to have been “created” by Thales of Miletus (625-545 BC), who was an astronomer, philosopher and one of the Seven Sages of Greece, a group of wise men who were collectively renowned throughout the Ancient World for their knowledge and wisdom. The constellation is circumpolar, and can be seen by observers located between +90° and -10° of latitude. Ursa Minor is the 56th largest constellation, occupies a surface area of 256 sq/degrees, and throughout history has been invaluable for navigation as it contains Polaris, also known as the North Star.
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