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other famous red supergiant star, Betelgeuse, in the constellation Orion the Hunter. Both Antares and Betelgeuse can clearly be seen as reddish stars, but not in the same sky. As a rule of thumb, when you see Antares in the sky, you won't see Betelgeuse because it will be below the horizon. Why? Simply because these two stars are located on opposite sides of the sky dome, and thus they never appear at the same time.
• Both Antares and Betelgeuse are interesting because they are near the end of their lifetimes. Massive supergiant red stars are expected to explode as supernovae. The supernova could happen tomorrow or millions of years in the future. Astronomers don't really know for sure. These stars are far enough from us (hundreds of light-years) that the deadly radiation probably won't harm Earth.
• Antares is truly an enormous star, with a radius in excess of 3 Astronomical Units (AU). One AU is the Earth's average distance from the sun. If by some bit of magic Antares was suddenly substituted for our sun, the surface of the star would extend well past the orbit of Mars!
• Antares is classified as an M1 supergiant star. The "M1" designation says that Antares is reddish in color and "cooler" than many other stars. Its surface temperature of 3500 kelvins (about 5800 degrees F.) is in contrast to about 10,000 degrees F. for our sun. Even though Antares' surface temperature is relatively low, Antares' tremendous surface area - the surface from which light can escape - makes this star very bright. In fact, Antares approaches 11,000 times the brilliance of our puny sun, a G2 star - but that is just in visible light. When all wavelengths of electromagnetic radiation is considered, Antares pumps out more than 60,000 times the energy of our sun!
• Bottom line: The star near the moon on Monday morning, March 4, 2013, is Antares - considered the Heart of the Scorpion in the constellation Scorpius. It is a red supergiant star, destined to explode someday.
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