Yesterday we talked about taking some of the heat out of global warming by planting reflective crops. The more solar radiation we reflect, the less is emitted as terrestrial radiation to heat up the green house gases in our atmosphere. But I know what you're thinking: Can't we just launch massive space mirrors into orbit and preemptively keep the sunlight from entering our atmosphere? Well, it's certainly one of the planet hacking options on the table. University of Calgary environmental scientist Dr. David Keith is a big supporter of this geoengineering approach to fixing the planet. Keith presented the idea at a 2007 climate change conference in Cambridge, Mass. Need to prevent ice from melting on Greenland? Simply throw some space mirrors up there to provide some shade. The potential cooling factor for this planet hacking scheme is immense, but the challenges and risks involved are obvious.

NASA's new Kepler telescope will help us pinpoint Earth-like planets spinning around distant stars, but now astronomers have something else to watch out for when eyeing other cosmic neighborhoods. Over the last 20 years, we've discovered hundreds of extrasolar planets, all orbitally bound to central stars like chicks to a mother hen. However, just like hamsters and mythological titans, sometimes these distant suns wind up chowing down on their young. Recent computer models indicated that it was possible for a parent star to pull a planet in with its gravitational pull and absorb it. As you might imagine, this is extremely important data for planet hunters to keep in mind. After all, who wants to go to all the trouble of exploring, colonizing and maybe even terraforming a distant world all so its sun can gobble it up?

One thoughtful gaze into a clear night sky is enough to put our measly little lives in proper context. All those pinpricks of light have been traveling across the cosmos for billions of years, from stars born in a truly ancient galactic past. Last week, astronomers spotted something in the sky that surpasses everything we've seen before. According to New Scientist, NASA's Swift satellite spotted the gamma radiation burst from a star exploding 13 billion light-years away. Again, that's 13 BILLION years in the past -- a mere 640 million years after the big bang. Following the April 23, 2009, event, astronomers from around the world turned their attention to the inferred afterglow.

Space Food: Orbital Curries and Lunchroom Politics

With recent news of Earth's orbital population reaching an all-time high of 13 again, I'm sure a lot of you were wondering the same thing: Are there any good places to eat up there? Fine dining above the exosphere is certainly looking up, so now's as good a time as any to look at what kind of grub astronauts, cosmonauts and taikonauts can stuff into their free-floating bellies.

While there's still more space junk up there than anything, the human space population reached its peak at 13 today, according to an article on This feat ties the record set in March 1995. Let's take a look at how it all breaks down in space. First, you have the space shuttle Discovery up there with a crew of seven astronauts. Three crew members from the U.S., Russia and Japan are hanging out on the International Space Station awaiting the pending arrival of the Russian Soyuz TMA-14 spacecraft and its three-person crew (one of whom is a space tourist), currently en route. Back in 1995, the situation was similar, with three cosmonauts bound to switch places with the three-man crew aboard the Mir space station -- all while the seven-man crew of the space shuttle Endeavour carried out its own mission.

The Mars Odyssey spacecraft has discovered a curious sight on the red planet's northern planes: mud volcanoes spurting methane gas and sediment up to the icy surface. Think about that for a second. What do you need to have mud? And what produces methane gas? That's right, water and animals. This is not to say the Martian underworld is overrun with jersey cows or giant sand worms. Animals aren't the only source of methane, but scientists theorize that the gas could indeed be due to thriving microbes several miles beneath the Martian surface. Down there, warmer temperatures could theoretically permit things like mud and life to exist. This news, reported in a New Scientist article, comes on the heels of a recent geological study on Earth supporting the notion that ancient, subterranean extremophiles might have survived the catastrophic celestial bombardment of the Earths' crust 3.9 billion years ago.

We're Going to Venus -- With Balloons

NASA is currently formulating a plan to send several missions to Earth's other sister world, Venus, according to an article today in New Scientist. Numerous U.S. and Soviet spacecraft have made the journey in the past, including both unmanned satellites and unmanned surface probes. What sets this proposed Venus mission apart is the use of high-altitude balloons to study the planet's upper atmosphere.

With NASA's self-described "picture-perfect" launch of the Discovery shuttle last night, space just got infinitesimally more crowded. I don't know about you, but when I think about interplanetary space, I don't think of premium real estate or routes being issues. It's not like we're fighting over an affordably priced studio apartment in New York City. As it turns out, that's a pretty simple view of space traffic. Think about it. Thursday afternoon, astronauts on the International Space Station hit the deck as space debris zoomed close. In case you missed it, here's my fellow science blogger Robert Lamb's post about it. Now NASA is reporting that another piece of junk is heading toward the station and may alter the course of the inbound Discovery shuttle. These collisions or close calls aren't even counting satellites crashing into one another, as a Russian and U.S. satellite did back in February, or the threat (albeit remote) that near-Earth objects present.

Astronauts aboard the International Space Station briefly evacuated to their Russian Soyuz escape pod today when NASA spotted space debris in the vicinity. Luckily for all concerned, 11 minutes and numerous panicky headlines later, everything was fine. The space junk passed within three miles of the station. Given the amount of damage that an orbital collision could inflict on the station, evacuations of this sort are standard operating procedure in space. In this case, the potential shrapnel was reportedly a small piece of an old spacecraft motor, but the amount of space garbage surrounding our planet is a growing problem. Some of these pieces travel at speeds as high as 17,500 miles per hour (28,164 kilometers per hour), and experts predict that there are as many as 40 million of them zooming around up there -- several thousand metric tons of cosmic litter. These bits range from abandoned launch vehicle stages to tiny flecks of paint.

When Black Holes Dance

Do you remember the part in Michael Jackson's "Beat It" video where the two rival gangs square up for battle, only for the situation to escalate into a full-blown dance number? Well, astronomers have long predicted that a vaguely similar relationship emerges when black holes meet in a cosmic standoff, and now they even have compelling evidence.