Frozen fire

This winter Japan will scout out a drill site for what will be the world's first offshore rig for "gas hydrates," a potential energy source that is untapped and immense. The Japanese government is sponsoring the research somewhere off the island nation's southern shores, and believes the hydrates in the region contain enough methane (natural gas) to meet Japanese demand for 14 years. Japan currently has to import 95 percent of its fossil fuels.

Gas hydrates are super-concentrated solids consisting of gas molecules trapped inside a cage of ice molecules. They're found beneath Arctic permafrost and under the ocean floor, and like the liquid propane in a gas grill tank, they expand forcefully under normal air pressure. The Gulf of Mexico has a large deposit of gas hydrates that received some media attention this year for clogging the first pipe BP tried to use to capture spewing wellhead oil during the Gulf spill.

The sheer volume of these hydrates challenges the imagination: Globally, the U.S. Geological Survey estimates there is twice as much methane trapped in hydrates as there is carbon in all the world's conventional fossil fuels.

The deposits are difficult to exploit, though. For one thing, the hydrates become unstable when extracted and can cause the surrounding sediment to buckle, which is a problem for mining equipment. The U.S. Department of Energy is spending $12 million to help ConocoPhillips test an experimental extraction technique on Alaska's North Slope, where there is enough recoverable gas from hydrates to meet total U.S. demand for over three years. The company plans to pump carbon dioxide into the ground and force methane out, sequestering the CO2 in the process. That approach may help pacify those who worry hydrate mining will inadvertently release methane into the atmosphere and accelerate global warming.

The Arctic hydrates could become commercially available as soon as 2015, but in the United States the present abundance of conventional natural gas gives little motivation to pursue an alternate source. In 2009 the country's available natural gas resources increased by 11 percent due to advances in shale gas mining-the biggest single-year jump in history. But nothing lasts forever. If Japan's venture is successful, hydrates may be the gas resource of the future.

New nova theory

A group of Polish astronomers is claiming to have solved a mystery regarding the origin of red novae. Most novae are of the blue variety and apparently occur when a white dwarf steals material from a companion star and then blows it off its surface. But the mechanics of red novae have elicited numerous theories.

After a red nova appeared in September 2008 (at 10,000 light-years away), the astronomers were able to dig up telescope observation data from as early as 2001 to see what happened leading up to the explosion. It turned out that two binary stars, so close together they practically touched, were orbiting one another every 1.4 days and increasing in speed. They finally merged into a single object, creating an explosion of gas that increased their brightness by a factor of 10,000. Lead astronomer Romuald Tylenda told Nature News that he thinks most red novae are caused in this way.