io9: planetology

Amazing Terraforming Projects - Real and Imaginary

Annalee Newitz — Fri, 27 Mar 2009 08:30:00 PDT

Humans have been terraforming since the earliest days of agriculture. We've got a gallery showing some of the Earth's most incredible terraforming projects - as well as what terraforming might look like on other worlds.

Additional reporting by Alyssa Johnson.

Mystery of the Off-Center Martian Ice Cap

Annalee Newitz — Mon, 22 Sep 2008 16:24:13 PDT

When summer hits the south pole on Mars, only half the ice on the pole melts. This leaves behind a strangely off-center chunk of water-and-carbon-dioxide ice, as you can see in this composite satellite image of the pole in summer. After analyzing climate data for several years, researchers have figured out what causes this weird pattern. It all has to do with winds coming off a gigantic crater, Hellas Basin, far to the north.

Winds blowing into and out of the 7-km deep crater create "Rossby waves," which in turn affect other weather systems. According to PhysOrg:

These waves reroute the high altitude winds on Mars and force the weather system towards the south pole. In the western hemisphere of Mars, this creates a strong low-pressure system near the south pole, and a high-pressure system in the eastern hemisphere, again near the south pole.

The temperatures in these two systems are different. The low-pressure system is the right temperature to cause carbon dioxide snow, which turns into ground frost. In the high-pressure system there's no snow. So you get ground frost without a snow covering. That means the ice cap is actually half frost, and half carbon dioxide snowy frost. The areas covered in snow don't melt off in summer because they reflect the sunlight. But frost grains can't reflect sunlight as well, and their shape actually exposes them to more sunlight. Which means they're easily melted in summer.

So that irregular polar cap you're seeing is the result of two winter different weather fronts coming together — one full of snow, the other causing frost. And in summer, only one side melts away — the non-snowy side. Which means there's always good carbon dioxide skiing on the western side of the Martian south pole, even in summer. Composite image via ESA/ Image Courtesy of F. Altieri (IFSI-INAF) and the OMEGA team.

Mars Polar Cap Mystery Solved [via PhysOrg]

Spirit, the Mars Rover, Left to Die Before Its Time

Annalee Newitz — Tue, 25 Mar 2008 07:00:19 PDT

The brave, unflagging Mars rover Spirit, who has lived on the Red Planet for almost four years, has been given a death sentence by the U.S. government. Right now, the little robot is resting on a sunny slope, waiting out the winter and preparing to do more tests on the Martian atmosphere. But now it looks like Spirit has rolled on its six wheels and done science experiments for the very last time. The U.S. government has forced NASA, this country's national space agency, to cut its budget by 4 million dollars. And that means only one rover, Opportunity, will survive. To say that this is a tragedy is an understatement.

The Mars rovers have been one of NASA's most proud achievements, and the information they gather today can help future planetary colonists tomorrow. While NASA is planning to land another rover on Mars within the next year, it's a shame to shut down a perfectly serviceable rover that could be supplementing what the new rover will learn.

With the Earth population skyrocketing, and urban overcrowding only likely to get far worse over the coming decades, preparing to colonize other plants should be more of a priority than ever. And every time we shut down a NASA program like the rovers, we step backward, away from the goal of leaving Earth. We also hinder our search for knowledge beyond this planet.

If I thought that money being cut from NASA's budget were going to developing renewable energy or bettering urban environments, I wouldn't be quite so pissed off. At least in that case, the money would be going toward building a better future Earthside. But it's not. Instead it's being used to bail out Bear Stearns.

Why doesn't a philanthropist like Bill Gates or Paul Allen step forward and write a check to save Spirit?

Spirit is an awesome robot, with awesome developers and operators at NASA, who braved the elements and mechanical problems to help advance our understanding of Martian geochemistry and atmosphere. The U.S. government should be ashamed that it has effectively killed fifty percent of its only science lab on another planet.

Above, you can see a picture Spirit took of its own tracks in the dust.

Kthxbai, Spirit, kthxbai.

UPDATE: NASA has just confirmed that the rovers will NOT be shut down! Hooray! [AP via Yahoo! News]

NASA Cut Means No More Roving for Mars Rover [AP via PhysOrg]

Titan Rises Behind Saturn's Rings

Annalee Newitz — Tue, 26 Feb 2008 07:00:36 PST

Haze-covered Titan, a moon of Saturn with a dense, cloudy atmosphere, was mapped extensively by the recent Cassini-Huygens space probe. The probe sent back beautiful space vistas like this one, whereTitan is the glowing globe behind Saturn's rings, and tiny moon Epimetheus is the small body you see floating above it. The space probe also gave up-close view of the surface of this moon, perhaps most famous for being the place where the aliens of 2001 have left a second monolith. What you may not have known is that the surface of Titan is ridged with sand dunes. Want to see them?

Above, you can see Titan's dunes. Below, there are dunes from an Earth desert. The sand formations are remarkably similar. Images via NASA.

Sulfuric Acid Floods Created Martian "Grand Canyon"

Annalee Newitz — Thu, 21 Feb 2008 07:00:26 PST

Unusual fan-shaped features cut into the Martian surface were caused by sulfuric acid "water" exploding from underground and sweeping across the surface of the planet. Yesterday a team of European and US scientists announced this finding, which is based on satellite data from a European Space Agency satellite in orbit around the Red Planet. Want to see the gullies dug by the sulfuric acid up close?

This is the "fan" filled with stair-like formations: The scientists figured out that it was caused by gushing liquid by setting up an experiment on Earth where they recreated the "gushing water" conditions in a sand bed and observed the structures the water carved out. Here's the Earth experiment: Images via ESA, NY Times, and Reuters.

Research Explains Origin of Martian Fans [NY Times]