Antares, one of the brightest stars in the southern sky, in the constellation Scorpio. It is over 400 light years from earth. It is a visual binary, or double, star; the main star is a red (thus, cool) giant, 480 times the size of the sun; its companion star is blue (hot) and too small to be visible without a powerful telescope.
See also: Astronomy.
21st Century Webster's Family Encyclopedia21st Century Webster's Family Encyclopedia - Anderson, Elizabeth Garrett to Arctic tern