NASA Deputy Administrator Shana Dale resigned from NASA effective Jan. 17, three days before President Bush leaves office and Barack Obama enters the White House.

She has served as NASA’s second-in-command since November 2005.

"It has been an honor for me to work with those who support America’s space program," Dale said. "It is a highly dedicated group, made up of individuals who share a deep passion for the missions of the agency. I will miss the cutting-edge missions, but most of all I will miss the incredibly talented people of NASA. It is a great team to be a part of, and I look forward to watching and cheering on the amazing accomplishments that are yet to come."

Dale’s previous experience includes working for the House of Representatives, the University of Texas system, the White House Office of Science and Technology Policy, and law firms in California. She is planning to enjoy time off with her family in January and February and consider options for the next phase of her career.

"It has been an honor and a privilege to work with Shana for these last three years," NASA Administrator Michael Griffin said. "I have benefited from her insightful and perceptive analysis in a host of difficult situations. Her long experience on Capitol Hill and in the White House has been a perfect complement to my own background, and enabled us to function as a team in managing NASA far more effectively than either of us would have done alone. Being a deputy is a very difficult job, and Shana has handled it superbly. She has offered incisive and perceptive analysis in a host of difficult situations, never hesitating to disagree with a prevailing opinion when that was the thing to do, but always supporting a final decision. I will miss her."

Separately, NASA astronaut Carl Walz is leaving the agency to take a job in the private sector.

Walz most recently served as director for the Advanced Capabilities Division in the Exploration Systems Mission Directorate at NASA Headquarters in Washington. In the division, he played a key role in developing technologies that will lead to greater capabilities in robotic and human exploration of the solar system. He oversaw work in many fields, including nuclear power and propulsion, human adaptation to spaceflight, and lunar exploration. Many of these programs will help humans return to the moon and develop a sustained presence there.

"NASA owes a great debt to Carl Walz for his service as an astronaut and the expertise and perspective he has shared with us in the Advanced Capabilities Division," said Doug Cooke, associate administrator for the Exploration Systems Mission Directorate. "The legacy of his leadership will be strongly felt in the next generation of manned space missions."

A veteran of four space shuttle missions and one International Space Station expedition, Walz spent 231 days in space. He and fellow astronaut Dan Bursch held the U.S. spaceflight endurance record of 196 days in space until April 2007.

Expedition 4, his last mission, launched aboard space shuttle Endeavour in December 2001. Walz, one of the station’s earliest inhabitants, set up equipment and experiments for the orbiting laboratory. He also completed two spacewalks during the mission, one in a Russian Orlan suit to outfit the Russian-supplied docking compartment and one in a U.S. spacesuit to prepare the station for its first truss segment. His spacewalks lasted a total of 11 hours, 52 minutes.

A retired U.S. Air Force Colonel, Walz also flew on STS-51 in September 1993, STS-65 in July 1994 and STS-79 in September 1996.

Walz and the STS-51 crew deployed the U.S. Advanced Communications Technology Satellite and the Shuttle Pallet Satellite. He also took a seven-hour spacewalk to evaluate tools for the Hubble Space Telescope servicing mission during that flight.

During STS-65, Walz and the crew worked in the second International Microgravity Laboratory spacelab module and conducted more than 80 materials and life sciences experiments. That mission completed 236 orbits of Earth, traveling 6.1 million miles and setting a new flight duration record for the shuttle program.

On STS-79, the seven-member crew docked with the Russian Mir station and set a record for docked mass in space. That mission also completed a crew transfer, provided vital supplies to the Mir, and conducted important research and technology demonstrations.

NASA selected Walz as an astronaut in January 1990. In addition to his flights, he served in a variety of technical and management positions within the Astronaut Office in Houston.