ABOARD AIR FORCE ONE: Hailing NASA's ''mind-boggling'' Mars landing of the Curiosity rover, President Barack Obama urged the scientists operating the craft on Monday to phone home immediately if they find any extra-terrestrials.    

''If in fact you do make contact with Martians, please let me know right away,'' Obama told controllers at the Jet Propulsion Laboratory in California.

''I've got a lot of other things on my plate, but I suspect that that will go to the top of the list. Even if they're just microbes, it will be pretty exciting.''

Obama spoke by phone from Air Force One as he flew to a campaign stop in the state of Iowa eight days after the car-sized rover landed on the Martian surface.

The touchdown followed a complex series of maneuvers involving intricately timed rocket firings, a huge parachute and cables lowering the craft to the Mars surface.

The two-year, $2.5 billion Curiosity mission includes looking for environmental conditions that might have given rise to life. However, as high-tech as it is, the nuclear-powered rover doesn't have the tools needed to detect living or fossil microorganisms. Instead, the rover will hunt for life's chemical building blocks.

''Curiosity stuck her landing and captured the attention and the imagination of millions of people not just across our country but people all around the world,'' Obama told the controllers, many of whom remained at their consoles.

''It's really mind-boggling what you've been able to accomplish.''

About to begin a three-day bus tour in Iowa, Obama couldn't resist a political point, vowing to resist efforts to cut spending on basic science. ''I'm going to give you guys a personal commitment to protect these critical investments,'' he said.

He also couldn't resist teasing Bobak Ferdowski, the flight director for JPL's Mars Science Laboratory, whose cool demeanor and Mohawk hairstyle made him an overnight Internet sensation after Curiosity's landing.

''I've in the past thought about getting a Mohawk myself. My team keeps discouraging me,'' Obama said to laughter from the JPL team. ''It does sound like NASA's come a long way from the white shirts, dark-rimmed glasses and pocket protectors.''