I can hear the moonbats barking already: NASA's O'Keefe to Resign; Ex-Missile Defense Chief Tops List of Contenders

Meanwhile, a White House team is weighing five candidates and plans to announce O'Keefe's departure and pick a new NASA administrator by Thursday, according to a source familiar with the selection process.

Leading the president's list: Air Force Lt. Gen. Ronald Kadish, who retired in September after three years as the director of the United States' effort to develop a system to shield the country and its troops from a missile attack.

The other four men under consideration are former Congressman Robert Walker and former shuttle astronauts Ron Sega, Charles Bolden and Robert Crippen.