Alcor

Alcor


 I have chose Alcor because it is a common planet that I am familiar with and have learned about previously.
Chemicals: mainly Hydrogen
Location: ascension 13h 23m 55.5s, declination of +54° 55′ 31″
Stellar Classification: 80 Ursae Majoris

Alcor, classified as a red dwarf, form a naked eye double star in the handle of the Big Dipper asterism in the constellation Ursa Major with Mizar. Mizar is itself a quadruple system and Alcor is a binary, the pair together forming a sextuplet system. It is located at a right ascension of 13h 23m 55.5s and a declination of +54° 55′ 31″.

Alcor is one of the very few in reverse, a star that has a proper names but no Greek letter name. Instead, it is referred to as 80 Ursae Majoris and is a fourth magnitude (4.01) white class A (A5) hydrogen-fusing dwarf star with a temperature of 8000 Kelvin and a luminosity 12 times that of the Sun. Also, Alcor is binary. Sophisticated infrared observations in which the light from Alcor proper was blocked out reveal a close companion+ about a second of arc away. Common parallaxes and motions show it to belong to Alcor. From its brightness, the companion has a mass around a quarter that of the Sun, making it a class M3 dwarf. With a minimum separation of 25 Astronomical Units, the little one would take at least 90 years to orbit its more massive mate. While the Mizar stars are slow rotators with peculiar chemical compositions as a result of element separation, Alcor is a rapid spinner (218 kilometers per second, over 100 times solar). As a result, its atmosphere is stirred and its composition normal. It is, however, a slight pulsating variable. The inner five stars of the Big Dipper are all at roughly the same distance and all are normal hydrogen fusing main sequence dwarfs. Alcor's faintness next to the them is a vivid reminder of the role that mass plays in the stars. Alcor's mass is around 1.8 times that of the Sun. Alioth, on the other hand, with almost twice Alcor's mass, is almost 10 times brighter.

Sources:
Wikipedia, the free encyclopedia. (2015, September 22). Mizar and Alcor. Retrieved September 27, 2015, from https://en.wikipedia.org/wiki/Mizar_and_Alcor

Kaler, J. (2010, May 2). Alcor. Retrieved September 27, 2015, from http://stars.astro.illinois.edu/sow/alcor.html

 Visible Spectra of the Elements. (n.d.). Retrieved September 28, 2015, from http://www.umop.net/spctelem.htm