The constellation is associated with several myths, but the story in widest circulation says it represents Ida Ursa Minor and her sister Adrasteia Ursa Major , the nymph nurses who were charged with taking care of the infant Zeus, and preventing his father Cronus from discovering he was still alive. The story goes that Cronos was afraid of a prophesy that predicted his downfall at the hands of one of his own children, and in an attempt to avert his fate swallowed five of his children immediately after birth.
After Zeus assumed the Supreme-godship, in gratitude for the nyphs service he placed Adrasteia and her sister Ide in the heavens as the constellations of Ursa Minor and Ursa Major.
An unrelated, and much older myth holds that the seven component stars of the Little Dipper are in fact the seven daughters of Atlas, collectively known as the Hesperides. As well as the nyphs, the apples were guared by Ladon, a huge hundred-headed dragon. The best time to view the shower is from midnight to just before dawn, though, when observers can expect to see up to 10 meteors per hour. Pherkad, Gamma Ursae Minoris, is an A-type star with an apparent magnitude of 3.
It has the stellar classification A3 lab, which means that it is an intermediate luminosity supergiant. It is a very fast rotating star, with a rotational velocity estimated at kilometres per second. Its radius is 15 times solar and it is 1, times more luminous than the Sun. Delta Ursae Minoris is a white main sequence dwarf of the spectral type A1V, approximately light years from Earth.
It has a visual magnitude of 4. The name is sometimes also spelled Vildiur, Jildun, Yilduz and Gildun. Zeta Ursae Minoris is a main sequence dwarf belonging to the spectral type A3Vn. It is in fact on the verge of becoming a giant star, with 3. Zeta Ursae Minoris is also classified as a suspected Delta Scuti variable. Eta Ursae Minoris is a yellow-white main sequence dwarf star belonging to the spectral class F5 V.
It is It is visible to the unaided eye. Epsilon Ursae Minoris is a triple star system consisting of Epsilon Ursae Minoris A, a yellow G-type giant which is also classified as an eclipsing spectroscopic binary star, and another component, the 11th magnitude star Epsilon Ursae Minoris B, which is orbiting the primary binary star system from a distance of 77 arc seconds.
The luminosity of the binary system changes as a result of the components eclipsing each other, and the overall brightness varies from magnitude 4. It has an apparent magnitude of It is a satellite galaxy to the Milky Way. Most stars in the Ursa Minor Dwarf are old and there is little to no star forming activity going on in the galaxy. The Ursa Minor Dwarf galaxy was first discovered by A.
Wilson at the Lowell Observatory in Information provided by the Hubble Space Telescope in confirmed that the galaxy had a two billion years long period of star formation about 11 billion years ago and a straight forward evolution since.
NGC was discovered in by astronomer John Herschel. This galaxy stretches for around 85, light-years. In , a Type la supernova was discovered in NGC NGC , is a barred spiral galaxy located at around 67 million light-years away from us. It can be viewed with a 10 cm 4 in or larger telescope since it has an apparent magnitude of NGC is also classified as a starburst galaxy, indicating a high rate of star formation, thus its spectrum is dominated by stellar photoionization from young, hot stars.
NGC is an active supergiant elliptical radio galaxy , situated at around million light-years away from us. This galaxy has a Seyfert 2 active galactic nucleus, and it is one of the most extreme examples of a Seyfert galaxy. Seyfert galaxies are among the two largest groups of active galaxies, along with quasars. They have quasar-like nuclei with very high surface brightness.
The Ursids are a prominent meteor shower whose radiant appears to be Ursa Minor. The Ursids peak between December 18 and Ursa Minor is associated with two different myths. In the first myth, the constellation represents Ida, the nymph who took care of Zeus on the island of Crete when he was young, along with Adrasteia, the nymph who is associated with the larger Ursa Major constellation.
Zeus would eventually free his brothers and sisters and become the supreme god of the Olympians. In the second myth, the constellation represents Arcas, son of Zeus, and the nymph Callisto.
Callisto then roamed the forests for years until she came face to face with her son, Arcas. Arcas was scared of the great bear in front of him and drew his spear, but Zeus quickly intervened to prevent a tragedy. Arcas is frequently more associated with the Bootes constellation, the celestial herdsman. In an older myth, the seven stars that form the Little Dipper were said to represent the Hesperides, the seven daughters of Atlas. Home » Constellations » Ursa Minor Constellation. Ursa Minor remains among the 88 modern constellations where it holds the 56 th place in terms of size, covering around square degrees.
Polaris is the brightest star in Ursa Minor. Another star, Kochab, is slightly fainter than Polaris, being the second-brightest star in Ursa Minor. Kochab also held the title of the North Pole Star several thousands of years ago. The constellation of Ursa Minor, just like its grander counterpart, Ursa Major, is marked by the famous asterism, the Little Dipper. The Little Dipper asterism can be seen as the handle of a ladle, hence the North American name. There are no Messier objects present in the constellation of Ursa Minor.
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