Description. Alprazolam (Xanax) is a benzodiazepine used to treat anxiety and panic disorder. Benzodiazepines are used to relieve anxiety, nervousness, or tension. Benzodiazepines should not be used for anxiety, nervousness, or tension caused by the stress of everyday life.
Binary Stars. Spica. Spica, Alpha Virginis, is the brightest star in the southern constellation Virgo and the 16th brightest star in the sky. It is a blue subgiant star located at a distance of 262 light years from Earth. Spica is really a close binary star system.
A star's brightness is known as its magnitude. Astronomers rate the magnitude of a star with a scale that gives brighter stars a low number and dim stars a higher number. Each whole number on this scale is 2.5 times dimmer than the previous number. The brightest star the night sky is Sirius. With a magnitude of -1.46, it is almost 15 times brighter than a star with a magnitude of zero. Stars with a magnitude of 8 or more are too dim to see with the naked eye. Stars are identified by their color, which indicates their temperature. They are divided into what are known as spectral classes. These classes are O, B, A, F, G, K, and M. Class O stars are the hottest and are blue in color.