Lunar Reconnaissance Orbiter NASA From the moment Neil Armstrong planted his boot on the moon, we have felt well acquainted with the place. It's cold, cratered, dusty and sterile. What else is there to know?
Plenty, actually. So far, astronauts have visited only the relatively barren lunar equator — the moonscape of our imagination — and when Armstrong first landed on the surface back in the headstrong, computer-weak Apollo era, many of today's detailed reconnaissance technologies didn't even exist. So, scientists still don't know much about the moon's water-ice stores or its mineral composition or the variances in its gravitational field. No one has ever even seen the shaded regions at moon's poles.
That should change this fall when NASA launches its Lunar Reconnaissance Orbiter (LRO), a $491 million mission that will provide the definitive moon, finally enabling scientists to discuss it with the same level of detail as, say, Saturn or Mars. LRO will gather measurements from a low orbit of about 39 miles (50 kilometers) for a full year. The orbiter's camera will zoom in up to three times closer than the one-meter-resolution imaging from the 1970s (which was roughly as close as you can get to your backyard today on Google Earth). Researchers will compare LRO's images with the reams of on-the-ground pictures taken from astronauts' rover-based journeys around the moon. It will also study the Apollo 11 landing site, meaning that we might actually get another look at humankind's most famed footprint, nearly four decades later. LRO may in fact turn out to be an Apollo buff's dream: the orbiter will collect detailed images of every Apollo landing site, not for nostalgia but as part of a thorough search for landscape changes that could reveal how much space debris has walloped each site since the astronauts were last there. "We have no other place in the universe where we can compare [what it looked like] 40 years ago with what it looks like now, at almost the same resolution," says Jim Garvin, chief scientist at NASA's Goddard Space Flight Center and one of the space agency's earliest LRO proponents.

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