Pasadena - The head of Nasa visited the Jet Propulsion Laboratory where engineers are working on a proposed mission to lasso a small asteroid and drag it closer to Earth for astronauts to explore.
During visit on Thursday, Nasa Administrator Charles Bolden viewed a prototype ion engine that JPL engineers are developing with counterparts at Nasa's Glenn Research Centre in Cleveland.
Nasa is under orders to send astronauts to an asteroid as a stepping stone to Mars. The space agency has decided to speed up the timeline by capturing a small rock in 2019, parking it near the moon and sending a team of spacewalking astronauts to explore it in 2021.
The White House's budget released in April proposes $105m to jumpstart the mission, which may eventually top $2.6bn.