WASHINGTON - U.S. President George W. Bush signed into law the NASA Authorization Act of 2008 (H.R. 6063), a policy bill that endorses U.S. plans to return to the Moon, sets budget targets for NASA programs and requires the agency to conduct an additional space shuttle flight to deliver a multibillion dollar science payload to the International Space Station.

The bill also baselines two space shuttle logistics flights to the space station that NASA had been required to label "contingency" since it lacked White House approval for them.

H.R. 6063 was one of a dozen bills the White House announced Oct. 15 that Bush had signed earlier that day.

The White House statement announcing the slate of newly signed bills says H.R. 6063 "requires NASA to add to its baseline flight manifest two Space Shuttle missions to the International Space Station and take all necessary steps to fly a third additional Shuttle mission; requires NASA to take steps to ensure that the International Space Station remains viable through at least 2020; and affirms congressional support for U.S. space exploration policy."

The U.S. Congress sent the bill to Bush Oct. 6. Under U.S. law he had until midnight Oct. 17 to sign the bill or else it would have been considered vetoed by default.

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