Washington, Apr 29 (DPA): The search for life will be a key part of future space exploration, a scientist involved in reviewing scientific endeavours in space said Wednesday.

Steve Squyres, a scientist at Cornell University who has been a key researcher on the Mars rover project, said an ongoing once-a-decade review of solar system science to recommend projects to NASA has developed a long-list of potential projects focussed on the search for life in space.

"Astrobiology is really central to what we should be doing next in exploration," he told reporters.

Possible missions include a Mars trace gas orbiter to study methane in the Martian atmosphere, which could be a byproduct of life; a three-step mission to bring rock and dirt samples from Mars back to Earth; an orbiter with radar to look for signs of a possible liquid ocean under the ice of Jupiter's Europa moon; and an orbiter to visit Saturn's Titan moon.

The review of possible projects should be completed later this year after scientists narrow down their wish list of possible expeditions.