Now that the August 2009 issue of Astronomy is in the mail or already in hand, we’ve updated Astronomy.com with our newest web extras to give subscribers exclusive complementary information to this special issue about our return to the Moon. Take a sneak peek inside the August 2009 Astronomy magazine . If you subscribe to Astronomy , make sure you’re registered with Astronomy.com so you can access these great extras. Here are this issue's highlights...

The Jet Propulsion Laboratory’s Mars Exploration Program web site has a fun new feature — Ask Dr. C, “your personal Mars expert.” You can type in a simple question — the simpler, the better — and get a pretty good answer. A computer program tries to match your question with an extensive database of responses. The real Dr. C is Phil Christensen , a planetary scientist at Arizona State University. Christensen is the Principal Investigator for the 2001...

On May 15, the SETI Institute — the planet’s leading extraterrestrial searchers — launched “ Earth Speaks .” The project invites the public to submit proposed messages to alien civilizations. According to Thomas Pierson, CEO of the SETI Institute in Mountain View, California, “By submitting text messages, pictures, and sounds from across the globe, people from all walks of life will contribute to a dialogue about what humanity might say to intelligent...

OK, April Fool’s Day is over. Some pretty clever pranks bounced around the Net yesterday, including a rumor that Admiral Adama of Battlestar Galactica fame is being considered for the post of NASA administrator. And then there was the one about the International Astronomical Union (IAU) and Pluto. This tidbit apparently originated on the internal computer system of NASA’s Jet Propulsion Laboratory: "Based on new observational evidence of more...

Megacorps are practically lining up for the privilege of disseminating fantastic volumes of astronomical images to you, John and Jane Q. Public. Recently Google added a “Live from Mars” function to its 3-D visualization of Mars within Google Earth. The feature allows you to see images from the Mars Odyssey spacecraft. Now Microsoft says it will let you explore images from the Mars Reconnaissance Orbiter (MRO, pictured at right) within its web-based...

Richard Greenberg, a professor of planetary sciences at the University of Arizona's Lunar and Planetary Laboratory, is an expert in celestial mechanics and carries out NASA-sponsored investigations of solar system evolution and planet formation. He is also author of the current book Unmasking Europa . After NASA and the European Space Agency chose Jupiter’s moons — including Europa — as the next destination for a major planetary exploration mission...

Today, February 18th, marks the 79th anniversary of Pluto's discovery by American astronomer Clyde Tombaugh. Strange, when I wrote that, I almost typed “the planet Pluto.” But as you may know, the International Astronomical Union (IAU) decided Pluto is a dwarf planet — to be precise, a type of dwarf planet called a plutoid . Recently we received a letter from Robert F. Brown of Orleans, Massachusetts, suggesting that today, Pluto supporters the...

“There is an ocean beneath the icy crust of Jupiter’s moon Europa [pictured at right]. Strange creatures could be swimming in these alien waters, but so far no missions have been sent there to investigate this possibility.” So begins, " Hoping for Europa ," an article by Astrobiology magazine Editor Leslie Mullen. Squids from outer space — who could resist? Or will it be a balloon ride over the windblown surface of a hydrocarbon lake on...

You have probably heard that Google and NASA have finally released the Google Mars update for Google Earth. I finally got the time to install Google Earth 5.0 and play on the surface of Mars for a bit this morning. It’s amazing. I first heard about this project a couple of years ago after stumbling across a subculture of Google Earth devotees who were overlaying pieces of Mars on Google Earth to create simulated 3D views. It was, as they say, a “hack...

Astronomy magazine’s offices are located in an office park off I-94 in Waukesha, Wisconsin. I’m one of the lucky people here blessed with a corner window that provides a pretty wide view of the sky. In summer, I watch wicked thunderstorm systems scudding due east on their way to die over Lake Michigan. During early evenings — when you can sometimes find some of us in our offices dotting i’s and crossing t’s on the latest astronomical discoveries ...