NASA heads to moon as panel weighs its future

* Options for commercial launch service to station

* Moon probe set to launch Thursday

* Panel to issue report in August

By Irene Klotz

CAPE CANAVERAL, Fla., June 17 (Reuters) - As NASA prepared to launch its debut mission in a program aimed at returning astronauts to the moon, a presidential panel on Wednesday began looking at alternative ways to get there and whether the United States should even go.

The Lunar Reconnaissance Orbiter, scheduled to launch from Cape Canaveral Air Force Station at 5:12 p.m. (2112 GMT) on Thursday, is designed to map the lunar surface so NASA can find safe and scientifically interesting landing spots for future human missions.

The United States is shifting the focus of its human space program from research and technology development in low-Earth orbit with the space shuttle and International Space Station to an exploration initiative. That would culminate in the return of U.S. astronauts to the moon in 2020 -- a half-century after the pioneering Apollo lunar landings of 1969 to 1972.

NASA plans to retire the shuttle fleet in 2010 after eight more missions to complete space station construction. It would then shift funding to ramp up development of a pair of expendable rockets, known as Ares, and a beefed-up Apollo-style capsule called Orion that can ferry crews to the moon and other destinations.

Orion's debut flight to the space station is targeted for 2015 -- five years after the shuttle stops flying.