Emily Lakdawalla • Sep 17, 2009
Some first results from Lunar Reconnaissance Orbiter (or, I love LOLA)
As of Tuesday (September 15), Lunar Reconnaissance Orbiter (or LRO as I suppose I'm going to be forced to call it -- I really really wish they'd run a naming contest and given this bird a more graceful, one-word name) is now in its low, circular, science orbit and is gathering data. It launched on June 18 and has been in orbit since the 23rd. During the last two months, it's been far from idle. It's been in its commissioning phase -- turning on its science instruments one by one, gathering some preliminary data, running multiple instruments at a time, then running through tests like moving solar panels while taking a photo to see how badly it smears the image data.
So this morning they held a press briefing to showcase some of the early data captured through the commissioning phase. There was only one instrument principal investigator on the panel, and I was thrilled to see that it was David Smith, the head of the Lunar Orbiter Laser Altimeter or LOLA.
Why is LOLA so thrilling? It's because our understanding of lunar topography is pretty lousy. It's as lousy as Martian topography was before Mars Global Surveyor arrived with its Mars Orbiter Laser Altimeter, or MOLA. MOLA absolutely revolutionized our understanding of Mars as a planet. It showed us what was high and what was low. It revealed features that were invisible in photos but whose subtle effects were noticeable in topography. And it created a precise control network for photos of the Martian surface from all the different orbiters that have been there in the past. With apologies to the MOC team, I think that MOLA topography was the greatest result of the Mars Global Surveyor mission; it's a critical data set that won't be supplanted for decades.
So I'm looking forward to LOLA doing the same to usher in a flurry of new discoveries about the Moon. LOLA gathers data along a line directly beneath the spacecraft, so it will take a long time for it to cover the entire globe. But since LRO is a polar orbiter, all those ground tracks converge at the poles, so the first map shows pretty good coverage of the south pole. It's absolutely lovely, the data set we've been missing for The Moon. There is wonderful detail. There are flat-floored craters and central peak craters. There's a couple of peak ring craters. I'm intrigued by the "wall" of bright red high elevation peaks that march across the image from its center to the right-hand edge. I can't say whether that's just an accidental wall built up from overlapping crater rims, or if it's an incredibly degraded bashed up remnant of some ancient great big impact basin. Whatever it is, it's cool.
Some other interesting early results came from Diviner, an instrument that measures the temperature of the surface:
They showed this pretty picture from the Mini-RF instrument without much comment except that it was instrumental in helping with the selection of Cabeus A as the target of LCROSS. Also significant -- but unmentioned -- is the fact that this Mini-RF is a duplicate of the one that was flying on the Chandrayaan-1 mission; in a sense, that instrument team is continuing work that began a year ago.
This image from LEND, the Russian-built Lunar Exploration Neutron Detector, really stirred up the press. Vondrak commented that the early results do show hydrogen as predicted in permanently shadowed regions near the south pole. "The surprising thing about the LEND observations is that while it confirms that there is hydrogen near the lunar south pole region, it also seems to indicate that the hydrogen is not confined to permanently shadowed regions. Some contain hydrogen; some do not; and in addition there appear to be concentrations that are not confined to permanently shadowed regions." When the press asked a bunch of questions about what this means, he answered, "you're asking the same questions that the science team members are."