A congressional panel grilled NASA chief Charlie Bolden today (July 12) on Capitol Hill, repeatedly asking him why the space agency has yet to choose a design for its next-generation heavy-lift rocket. Last year Congress gave NASA until mid-January 2011 to pick a design for the rocket, known as the Space Launch System, that will carry astronauts on deep space missions. NASA still has not made an official decision, and members of the House of Representatives' Committee on Science, Space and Technology took Bolden to task. "We've waited for answers that have not come. We've pleaded for answers that have...