Main Sequence

A classification of stars that shine via hydrogen thermonuclear fusion in their cores. Such stars are stable, with no major pulsations or variations. Most stars spend the greatest portion of their lives on the main sequence.


Star Color and Energy Stars come in a variety of sizes and colors, but...

Radio Programs

Moon and Aldebaran Igniting the core of a star Saturday, July 11, 2015
Vega A middle-aged star with a difference Saturday, June 6, 2015
Alphecca Stellar siblings with different futures Saturday, June 28, 2014
Vega Stands High Crowning the early evening sky Saturday, September 7, 2013
Alkaid Anchoring the Big Dipper Sunday, July 28, 2013
Megrez Holding together the Big Dipper Saturday, July 27, 2013
Zeta Puppis A rare stellar hothead Wednesday, April 3, 2013
Adhara Another impressive “dog” star Saturday, March 2, 2013
Menkar A constellation with a case of the big head Sunday, November 18, 2012
Summer Triangle The brilliant Summer Triangle Sunday, July 8, 2012
H-R Diagram Drawing the lives of the stars Saturday, July 7, 2012
Companions Companionship in the evening sky Tuesday, June 26, 2012
Sirius A close, bright stellar neighbor Monday, January 30, 2012
Moon and Companions A big astronomical dwarf Friday, October 21, 2011
Mu Herculis A faint but long-lived neighbor Tuesday, May 4, 2010
Companionable Stars Good places to hunt for habitable planets Tuesday, March 9, 2010
Moon and Regulus The Moon and the lion's "regal" heart Saturday, February 27, 2010


©2015 The University of Texas McDonald Observatory