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Asteroid 2003 SD220 will safely fly past Earth on Dec. 24 at a distance of 6.8 million miles (11 million kilometers). Scientists at NASA's Jet Propulsion Laboratory in Pasadena, California, have generated the highest-resolution images to date of this asteroid using the Deep Space Network's 230-foot (70-meter) antenna at Goldstone, California. The radar images were acquired between Dec. 17 and Dec. 22, when the distance to this near-Earth object (NEO) was narrowing from 7.3 million miles (12 million kilometers) to almost the flyby distance.

The U.S. wind power industry is celebrating after reaching a new milestone in November: 70 gigawatts (GW) of generating capacity.

"That's enough to power about 19 million homes," says Michael Goggin, senior director of research at the American Wind Energy Association (AWEA).

In a big step forward for wild bison and all Montanans, today Governor Steve Bullock agreed to expand year-round habitat for wild bison in Montana outside Yellowstone National Park.  Historically, thousands of wild bison have been hazed or slaughtered as they migrated from Yellowstone into Montana in the spring. This decision represents a significant change in bison management.

Following is a statement from Matt Skoglund, Director of the Northern Rockies Office at the Natural Resources Defense Council:

“Giving wild bison from Yellowstone year-round habitat in Montana is a welcome holiday offering from Governor Bullock. While I’d certainly love to see the state go further, this decision is a big step forward for wild bison in Montana, and it will show that wild bison and people can successfully share the Montana landscape outside Yellowstone National Park. When you consider this from a science, economics, public opinion, or common sense perspective, it makes sense for Montana to give wild bison from Yellowstone year-round habitat in the state.”

The amount of methane gas escaping from the ground during the long cold period in the Arctic each year and entering Earth's atmosphere is likely much higher than estimated by current carbon cycle models, concludes a major new study led by San Diego State University and including scientists from NASA's Jet Propulsion Laboratory, Pasadena, California.

The study included a team comprising ecologists Walter Oechel (SDSU and Open University, Milton Keynes, United Kingdom) and Donatella Zona (SDSU and the University of Sheffield, United Kingdom) and scientists from JPL; Harvard University, Cambridge, Massachusetts; the National Oceanic and Atmospheric Administration, Boulder, Colorado; and the University of Montana, Missoula. The team found that far more methane is escaping from Arctic tundra during the cold months when the soil surface is frozen (generally from September through May), and from upland tundra, than prevailing assumptions and carbon cycle models previously assumed. In fact, they found that at least half of the annual methane emissions occur in the cold months, and that drier, upland tundra can be a larger emitter of methane than wet tundra. The findings challenge critical assumptions in current global climate models. The results are published this week in the Proceedings of the National Academy of Sciences.

All over the planet, every day, oceans send plumes of sea spray into the atmosphere. Beyond the poetry of crashing ocean waves, this salt- and carbon-rich spray also has a dramatic effect on cloud formation and duration.

In a new paper published this week in the journal Proceedings of the National Academy of Sciences, Colorado State University atmospheric scientist Paul DeMott finds that sea spray is a unique, underappreciated source of what are called ice nucleating particles. These microscopic bits make their way into clouds and initiate the formation of ice, affecting the clouds' composition.