When starlight passes through a planet's atmosphere, certain elements absorb specific wavelengths of light, and these show up as dips in the spectrum.
If aliens are out there, the best shot at finding them—assuming they resemble the life-forms on Earth—is to look for planets like ours. E.T.'s home will probably require an atmosphere to have liquid water and keep out solar radiation, so astronomers search for perfectly sized and situated planets surrounded by blankets of life-supporting gases like oxygen and water vapor. Now they know how to recognize that ideal atmosphere.
Scientists have repeatedly touted the possibility of turning algae into biofuels. Now a Florida-based company called Algenol is working with Dow Labs in Texas to convert carbon dioxide produced by algae farms into ethanol, which will then be used to make plastics. Even better, the oxygen byproduct left over from the conversion can be used to produce cleaner, more efficient coal power.
Among the hot new ideas afloat in the world of geoengineering is biochar, a form of charcoal that some say could significantly help in carbon sequestration in the future. Re:char, a fledgling company working out of a corner of a cluttered warehouse in a shared artist loft in Brooklyn, New York, is experimenting with biochar production on a very small scale.
By Hillary RosnerPosted 06.11.2009 at 6:45 am 1 Comment
The Big Picture: Carbon-restricting legislation, if enacted, will discourage the use of coal, the dirtiest of all fossil fuels. Natural gas is cleaner but still emits carbon dioxide when burned. Both will be used for decades, but carbon-capture technology could clean them up until they can be replaced completely.
Where We Are Now: 1,460 GW
What We Need by 2050: 3,830 GW (all of it clean)
Tech to Watch: Carbon-to-cement
By Amber SassePosted 04.22.2009 at 11:25 am 2 Comments
Yep, that’s right. Mickey proves Kermit wrong in the whole “it’s not easy being green” arena with the release of Disneynature’s first film, Earth. Opening today in theaters, the movie follows three animal “families” on a journey for survival across our planet.
Last week, the owners of the Empire State Building announced they were going to turn their iconic New York landmark green — as in sustainable (the color is fine as is)
By Dr. Bill ChameidesPosted 04.17.2009 at 1:07 pm 1 Comment
PopSci.com welcomes Dr. Bill Chameides, dean of Duke's Nicholas School of the Environment. Dr. Chameides blogs at The Green Grok to spark lively discussions about environmental science, keeping you in the know on what the scientific world is discovering and how it affects you – all in plain language and, hopefully, with a bit of fun. PopSci.com partners with The Green Grok, bringing his blog posts directly to our users. Give it a read and get in on the discussion!
Despite all the talk about carbon capture, carbon footprints and carbon trading, carbon dioxide only causes nine to 26 percent of the greenhouse effect. That means that the majority of warming results from gases with a much lower media profile than the paparazzi-trailed starlet of global warming, CO2. In honor of last weeks' report in the Journal of Geophysical Research, which identified a brand new greenhouse gas, PopSci.com counts down the gases that bring us bikini weather in Antarctica and beachfront property in Montana.
Around half of our CO2 emissions aren't from big power plants, or even small power plants, according to researchers from the University of Calgary. They're from diffuse sources, like car exhaust, home heating and airplanes, which can't be easily sucked up at the source. Led by climate scientist David Keith, the Calgary group is working on technology that could soak those "diffuse emissions" right out of the air.
Their system is a kind of air scrubbing tower, which takes air and reacts the CO2 out of it by exposing it, in this case, to sodium hydroxide. Then the stuff goes through a few chemical intermediaries eventually leaving separated CO2 that can be piped away, and more hydroxide to feed back into the scrubber.
Here’s why you might be worried: Burning oil, coal, gas, wood or other organic materials uses molecular oxygen, the O2 we breathe, to break carbon-hydrogen bonds and release energy. This reaction, better known as combustion, also pairs each broken-off, positively charged carbon atom with two negatively charged oxygen atoms, forming carbon dioxide, or CO2.