One of the European Space Agency 's (ESA) greatest gifts marks its fifth year in space. Launched February 28, 2002, from Kourou, French Guiana, Envisat is the largest and most complex environmental satellite. The spacecraft has gathered more than...

This image made by the Chandra X-ray Observatory in 2004 shows SN 1572, the youngest supernova remnant in the Milky Way. It is sometimes referred to as “Tycho’s nova,” after the 16th century astronomer who observed and wrote about it...

I'm not a slouch when it comes to observing. In fact, I'd go so far as to say I'm a pretty good observer. I've recorded a lot of "firsts" and "bests" during my random walk through the sky. I've also observed with...

Supernova 1987A shines brightly near the center of this photo, taken March 2, 1987. The wispy gas clouds of the Tarantula Nebula lie to the supernova’s left. Marcelo Bass/CTIO/NOAO/AURA/NSF It was 20 years ago today, A shock wave started 87A, Its...

What do an asteroid and a tsunami have in common? Plenty, it turns out. It seems one of the toughest issues for politicians to address in a timely way is a natural hazard with potentially catastrophic consequences but whose risk of actually occurring...

The Sun shone brightly on the snowy slopes of Aspen during this week’s supernova workshop. But the participants, including your humble correspondent, were more interested in exploding stars. Larry Marschall With 12 inches of fresh powder on the...

NASA/Philip Stooke Three cheers for University of Western Ontario geologist Philip Stooke, who deserves the Photoshop Wizard of the Year award for his painstaking restoration of panoramic images shot by the Lunar Surveyors in the 1960s. In his spare time...

I've created a gallery featuring some pictures of the Winter Star Party — a sold-out event held February 12–18 at Big Pine Key, Florida. Click here to view these images.

Walker Books Today marks the 534th birthday of Nicholas Copernicus, the Polish astronomer who published the first modern heliocentric theory, in the 16th century. Although this should be Copernicus' special day - after all, it's not every day...

Astrophotographer Jack Newton was one of Arizona Sky Village’s first inhabitants. His attached observatory houses a 16-inch Meade Schmidt-Cassegrain telescope. Newton routinely photographs the Sun and searches for supernovae. Michael E. Bakich In...

Tectonic fractures within Candor Chasma retain their ridge-like shapes as the surrounding bedrock erodes away. The fractures have a light tone presumably because liquid water altered their chemical composition. NASA/JPL/ University of Arizona The Mars...

The C2 suborbital spaceship will take a contest winner 62 miles (100 kilometers) above Earth’s surface for a brief joyride. Space Adventures, Ltd. As ordinary citizens jump into the Space Race , they may notice the tax collector following in hot...

The lack of a telescope is no problem for astronomy beginners. When you attend a star party, just about everyone there is willing to let you look through his or her scope. Last night, here at the Winter Star Party in Big Pine Key, Florida, my wife Mary...

Martin Willes sets up his Astrophysics refractor with a Baader Energy Rejection filter and Hydrogen-alpha filter. Dick McNally Florida's famous Winter Star Party is up and running with a sold-out crowd enjoying temperatures in the 80s. Many telescopes...

This year, the number of objects in orbit around Earth 4 inches (10 centimeters) or larger reached 10,000. Many smaller bits of space junk also litter space. All of them — large and small — threaten to start colliding into other bits of junk...

Each February thousands of people flock to Tucson to attend the Tucson Gem and Mineral Show , where mineral, gem, and meteorite dealers offer specimens for collectors to take home. The event consists of several overlapping shows held at numerous hotels...

The sky contains approximately 41,253 square degrees of measurable "surface" area. Trust me, I'm going somewhere with this, and it's not to math class. Since 1930, when astronomers formalized the number of constellations and their boundaries...

If you want to observe showy Saturn and its ephemeral rings at their best and brightest in 2007, then plan on setting up your scope tonight. That is when the ringed planet reaches opposition — Saturn and the Sun lie directly opposite one another...

Graffiti: we do it on trees, rocks, subway cars, and bathroom stalls. The most popular form of all is simply scrawling our initials, sometimes adding a heart and the initials of that special someone. Now you can send your very own "Kilroy was here"...

Thanks to an alleged lovelorn meltdown, NASA has received as much general-media coverage this week since Neil Armstrong and Buzz Aldrin treaded on the lunar surface. According to police reports, astronaut Lisa Nowak went bonkers, drove across the southern...

Mercury stands above the western horizon after sunset in this view from 2005. Lee Coombs Last evening was clear in Wisconsin and, with the temperature hovering in the single digits, relatively balmy compared with the past few nights. I took the opportunity...

For me, the best kind of observing is naked eye — and before bedtime. This week, Mercury and Venus fit that bill. Before dinner tonight, check out the planetary pairing in the west-southwest. Even a sub-zero wind chill tonight won't dissuade...

The top story this week in our part of the country is the Arctic air mass that has settled over the land, cracking water pipes, chapping lips, and closing schools for fear that students would turn into popsicles waiting for the bus. Forecasters whipped...

Springer A new book just arrived at the office, and I'm pretty jazzed about it because it covers a topic not often addressed — interpreting stellar spectra. Spectroscopy: The Key to the Stars by Keith Robinson (Springer, New York, 2007) is part...

The mainstream medium is already calling it the "smoking-gun report." Today, the International Panel on Climate Change (IPCC) released a summary of its findings to a worried world. (Don't forget that 2006 was the warmest year in the United...