• December 21, 2011   BY  

    It’s true: no two snowflakes are alike. But they come in more shapes than you might think. Check out some samples in this slideshow. Continue reading

  • December 21, 2011  

    The Environmental Protection Agency unveiled new standards Wednesday to curb mercury emissions from coal- and oil-fueled power plants around the country. Gwen Ifill discusses the announcement with the Electric Reliability Coordinating Council’s Scott Segal and the Natural Resources Defense Council’s John Walke. Continue reading

  • December 20, 2011    

    This ‘planet line-up’ displays the first two Earth-size extrasolar planets, Kepler-20 e and Kepler-20 f, together with the Earth and Venus, ranked by their size. Image by Tim Pyle. Scientists have found two fiery hot, Earth-sized exoplanets whizzing around a … Continue reading

  • December 20, 2011  

    In other news Tuesday, a snowstorm howled across the Great Plains for a second day, killing at least six people. High winds and heavy snow closed major highways in five states. Also, Egyptian troops and riot police raided Cairo’s Tahrir Square in a new bid to evict people protesting military control. Continue reading

  • December 19, 2011    

    The bright orange Elkhorn coral off the coast of Florida have been devastated by a disease that scientists have tracked to human sewage. Elkhorn coral was at one time the most common coral in the Caribbean, but has declined by … Continue reading

  • December 16, 2011    

    Several dozen supporters of U.S. Army Private Bradley Manning gathered Friday at the entrance to Fort Meade, where his preliminary hearing is taking place. Photo by Chip Somodevilla/Getty Images. Months of debate and demonstrations over the flood of classified U.S. … Continue reading

  • December 15, 2011    

    In mid-July, NASA’s Dawn spacecraft swung into a yearlong orbit around Vesta, the second-most massive object in the asteroid belt between Mars and Jupiter. Since then, it has been snapping pictures of the protoplanet’s rugged surface and beaming them back … Continue reading

  • December 15, 2011   BY  

    On December 12, Dawn maneuvered into its closest orbit yet around giant asteroid Vesta. The spacecraft is now circling Vesta at an altitude of about 130 miles. Since NASA’s spacecraft dawn snapped into orbit around the object, it has been snapping pictures of the asteroid’s rugged surface and beaming them back to Earth. Continue reading

  • December 15, 2011  

    A new research breakthrough has enabled scientists to grow human tissue to repair or replace organs, and someday, maybe even limbs. Science correspondent Miles O’Brien reports. Continue reading

  • December 14, 2011    

    A worker at the “European Organization for Nuclear Research walks past a mural representation of the ATLAS Large Hadron Collider in Geneva, Switzerland.
    Continue reading