November 19, 2009 "How to Build a Planet," Meredith Hughes, CfA Where did the Earth come from, and how can we know? Is our solar system"normal," or not? How can dust particles no larger than those in cigarettesmoke clump together to make a planet thousands of miles across?

October 15, 2009 "10 Years of Chandra Discoveries," Andrea Prestwich, CfA Since its launch in 1999, the Chandra X-ray Observatory has revolutionized the science of X-ray astronomy.

September 17, 2009 "Black Holes and Runaway Stars," Warren Brown, CfA A massive black hole sits in the heart of our galaxy. Every so often, it slingshots a star outward at a speed of more than one million miles per hour - fast enough to escape the Milky Way completely.

May 21, 2009 "The Day We Found the Universe," Marcia Bartusiak On January 1, 1925, thirty-five-year-old Edwin Hubble announced findings that ultimately established that our universe was a thousand trillion times larger than previously believed, filled with myriad galaxies like our own. It was a realization that reshaped how humans understood their place in the cosmos.

April 16, 2009 "Because the World is Round," Patrick Slane, CfA Start with a rough inversion of the chord structure in Beethoven's "Moonlight Sonata." Interweave complex harmonies expressing simple statements about our world. Add shape-shifting guitar effects. The result is the song "Because" by The Beatles.

March 19, 2009 "The Second-Biggest Bang," Emily Levesque, CfA One year ago today, astronomers observed the brightest cosmic explosion ever recorded. This event, known as a "gamma-ray burst," was so far away that it took 7.5 billion years for light from the explosion to reach Earth, and was so bright that humans were able to see it with the naked eye.

February 19, 2009 "Galileo Opens the Door, Owen Gingerich, CfA Exactly 400 years ago the astronomical use of the telescope began, with Galileo Galilei in the forefront. His observations of the moon, Jupiter, Venus, and the sun gave crucial support to the new Sun-centered cosmology.

January 15, 2009 "WorldWide Telescope: Astronomy of the Future," Alyssa Goodman, CfA Astronomy is undergoing a second revolution just as dramatic as Galileo's. No longer must astronomers spend long hours in cold domes. Computers now allow scientists and laypeople alike to access the sky from their office or home.