Friday, December 16, 2011

The closest of lunar close-ups, now available

Go the the LROC QuickMap "and grow wise." Select the NAC footprints overlay from the left side of the QucikMap interface and study their individual patterns. Logically, the larger the footprint the higher the vantage point. If you look very closely, in a few places, more in one hemisphere than the other, there are the most narrow and smallest of NAC footprints. Those are the very closest of close-ups of the lunar surface, captured during a brief low-perigee phase in the LRO mission last August, part of the 8th release of LROC imagery to the Planetary Data System, December 15 [NASA/GSFC/Arizona State University].
It's a storied challenge for the most talented and best equipped amateur telescopes. The much studied nearside 'caldera' "Ina" is seen above prior to local sunset on January 6, 2010; a roughly 46 kilometer-wide LROC Wide Angle Camera (WAC) color (689 nm) field of view stitched from sessions in sequential orbits. (Down slope from the feature, to the east by southeast, younger surface material may be a hint of pyroclastic flow). A window of very low pass orbits LRO took over the lunar surface last August allowed LROC team members to take a few extreme close-ups, among those released December 15. One of these is detailed below [NASA/GSFC/Arizona State University].
Joel Raupe
Lunar Pioneer

LRO data collected June 14 - September 15, 2011 is now available through the Planetary Data System (LRO Node), the 8th such consecutive release. Details on its size and scope should be posted by the Lunar Reconnaissance Orbiter science teams shortly.

Among these data are the latest available images collected in those 90 days by the Lunar Reconnaissance Orbiter Camera (LROC) team at Arizona State University. The LROC QuickMap and other web-based indexes have been updated to include this newest set, though the LROC News System has been unusually quite, so far, announcing their availability.

From February 2010 (LRO orbit 2791) "Ina" (18.65°N, 5.3°E) is seen here in a montage of 10000 lines taken from both the left and the right frames of Narrow Angle Camera (NAC) observation M119815570. Ina is "an extremely young and unusual 3 by 2 km depression that may represent a gas eruption site on the Moon" [NASA/GSFC/Arizona State University]
Scientists are busy people. The image some of us have of Einstein, Bohr and Schrödinger lounging around a smoking salon or discussing the impossible melding of Quantum Mechanics and Special Relativity in a random walk in the park, relates with modern science as well as John Wayne's earliest movies match up with the real Wild West.

And it's an unusual set of images. Last August, for a brief period, LRO was brought closer to the lunar surface, to perilune heights sometimes below 24 kilometers. As discussed at the time the spacecraft afterwards returned to it's mission profile, low-eccentricity polar orbit of around 50 kilometers, but next month, to save fuel for its extended mission, the orbiter will be raised to the longer-term stability of a 100 kilometer polar orbit. As such, we're not likely to see LROC Narrow Angle Camera close-ups of the lunar surface as detailed as some collected in August until End of Mission.

It's a little misleading to post this latest, somewhat oblique raw LROC NAC August close-up of Ina. It's from the left frame of M168170208, and with a somewhat oblique resolution of 40 centimeters per pixel, from 24.19 km in altitude, it does not seem much more detailed than what the eye first sees looking at the same field taken from the left side of M119815570, from nearly twice the altitude. Other than for dramatic affect, the only reason to add the image above to the sequence is to provide some context.
 After spending a few hours looking through a sample of the LROC August close-ups, I'm reminded of something Charles Wood (LPOD) wrote after the first releases of LROC NAC images in 2009. He looked forward to the release and assembly of the mission's Wide Angle Camera imagery, he said. As breathtaking and beautiful as the NAC images were, they seemed almost too difficult to interpret without context. The science of the mission was not readily available to the unassisted human eye. The contact between one's nose and face is easy to see, but an inch away it can all seem like the same skin.

The full 40 centimeter per pixel close-up of the southern "contact" between Ina and "that which is not Ina" from LROC NAC M169170208L, orbit 9917, August 16, 2011. Incidence angle 43.28° The field of view above is around 230 meters across.
There may not be a lot of eye-candy in the LROC August 2011 close-ups, but those who are patient and observant, those who understand at least some of the context of what they are seeing in these images, will undoubtedly make new discoveries.


John Umana said...

Just magnificent work!

Joel Raupe said...

Still combing through the QuickMap close-ups, they appear grouped on the nearside equatorial latitudes, between August 13 and 16.

A bonus came when it finally occurred to us to check for Wide Angle Camera activity in that same space and time frame, and indeed. Some of these have resolutions of 40 meters per pixel, which may make for incredible improvements to nearside mosaics.

All of this has been well worth the wait.