The acting administrator of NASA, Michael Griffin, has set forth his letter of resignation, to enter effect on January 20th, as the 19th is a federal holiday. The date coincides with the Presidential Inauguration Date, when president-elect Barack Obama will take office at the White House. Though Griffin has yet to receive word that he is relieved of his duties, he was politically appointed to the position he now occupies and considers it a fair gesture to step down.

December 16th could be Griffin's last day as the head of the American Space Agency, and could see him leave his ninth floor office at NASA's headquarters in Washington DC. His family and closest friends are currently lobbying to Obama to keep Griffin on board, but the feeling in Washington is that a new team will step up to lead the troubled space agency, faced with the prospect of retiring its shuttle fleet in 2010 and remaining grounded until 2015 the earliest, when the new Ares exploration capsule is scheduled to be completed.

The list of possible replacements for Griffin has some of the most prominent names in space flight history on it, including the first American female astronaut to fly in space, Sally Ride and Wesley Huntress, former NASA space science chief, who played a part in several successful space missions, including the deployment of the Magellan Venus Radar Mapper and the Hubble Space Telescope.

The list also features the names of Scott Hubbard, a key member of the Columbia Accident Investigations Board and Alan Stern, former associate administrator of the Science Mission Directorate at NASA headquarters, and principal investigator of a Pluto mission.

But the man credited with most chances of occupying Griffin's position is Charlie Bolden, who could become the first Afro-American administrator of the space agency, after flying four space shuttle missions and helping deploy the Hubble Telescope. He also participated in the first joint US-Russian space flight. Bill Nelson, senior US senator from Florida, is said to endorse Bolden's appointment, having flown with the astronaut in a 1986 mission.