Year of the Comet
Comet C/2011 L4 (PANSTARRS)

PANSTARRS information

Comet C/2012 S1 (ISON)

ISON information

Web Extras
Go deeper into the stories of Astronomy magazine. These online features bring you additional research, interviews, photos, and more our editors turned up while creating the stories for this issue.
June 2009
Radial velocity method
Astronomers plan to use a new precise ruler to search for earthlike planets.
By Ashley Yeager // Published: April 27, 2009
John Mather
Learn more about the lives and ideas of June's "Astro Confidential" professionals.
By Karri Ferron // Published: April 27, 2009
Cassiopeia A
Associate Editor Daniel Pendick explains how astrophysics is a smaller specialty in the greater field of astronomy.
Published: April 27, 2009
NGC 1491
See more of this renowned astroimager's breathtaking work.
By Liz Kruesi // Published: April 27, 2009
Michael E. Bakich Rancho Hildago
In October 2008, I got to spend three incredible nights under a pitch-black sky.
By Michael E. Bakich // Published: April 27, 2009
June 2009 Reader Gallery NGC 2170
Explore some astounding objects in Monoceros.
By Michael E. Bakich // Published: April 27, 2009
June 2009 Moon Chaple
Use Robert Burnham's guide to the First Quarter Moon as you go out observing.
By Glenn Chaple // Published: April 27, 2009
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