Wednesday, December 26, 2012

New oblique view of Tsiolkovskiy central peak

The prominent, very distinctive central peaks of farside Tsiolkovskiy crater, from a new, scaled mosaic of the left and right frames of LROC Narrow Angle Camera (NAC) observation M1098059280, spacecraft orbit 14176, July 27, 2012; resolution between 4.6 and 5.3 (top) meters per pixel, captured 87.66 km over 20.44°S, 121.42°E, a point over 200 km west of the highest promontory. Larger versions available HERE  [NASA/GSFC/Arizona State University].
Joel Raupe
Lunar Pioneer

Each quarterly release of LROC data to the Planetary Data System (the twelfth, on December 15, covers the three months between mid-June and September), is not really complete until the KML index emerges, for viewing through Google Earth's lunar simulation.

Fortunately, the Lunar Reconnaissance Orbiter Camera (LROC) team made available to the public an incredibly useful set of improvements to their Web Map Server (WMS) Image Search tool, something that was already a real complimentary companion to the newer LROC QuickMap tool. Playing with the layers and search capabilities of the new tool, while studying the LUNAR landing site study, was enough to keep us busy.

The KML data are a fast and intuitive way yet to search directly for LROC NAC images, especially those with exceptionally high slew angles, the few oblique images. And the latest KML files appeared on the Massachusetts Institute of Technology servers December 21.

Since the very first grainy, misunderstood images of the Moon's far side were returned to Earth by the Soviet Union in 1959, Tsiolkovskiy immediately stood out, strongly underscoring the remarkable differences between the tidally locked hemispheres. LROC Wide Angle Camera (WAC) context view of the most conspicuous mare-flooded surface on the lunar farside, 185 km Tsiolkovskiy crater [NASA/GSFC/Arizona State University].
The oblique views are rare. Off nadir NAC observations are of a lower scientific value, perhaps, than the job of completing the high-resolution photography of the entire Moon, a goal the LROC team is closing in on. My favorite targets for these oblique views are never in the new batches, but there's always one or two that are breathtaking and unexpected.

Last September LROC's 11th release included an oblique look into the interior of Antoniadi, for example, that was then included in our post highlighting oblique views of Engel'gardt heights. Antoniadi, as it turns out, figures prominently in the aforementioned landing site study. Follow-up posts on that Eratosthenian crater, well inside the very ancient South Pole-Aitken basin, are in preparation.

Among the new, few oblique views that really stand out in the twelfth release is an off-nadir view of the central peaks of Tsiolkovskiy, shown up above. The complete field of view here is a highly re-sampled (less than 8 percent) version of what was originally a 6204 by 8955 mosaic (of LROC NAC M1098059280LR, swept up last July). It's reduced down to 580 x 800, or the maximum size allowable in a blogger post.

Because we derive vast amounts of valued-added imagery, in an image-intense subject of study, this last limitation has become a nagging problem we would like to solve.

Quarter resolution view of the LROC NAC mosaic shows some of the glory of the wider view, the eastern range and summit, as well as some of the considerable slumping of the degraded northern section of Tsiolkovskiy central peak [NASA/GSFC/Arizona State University].
We would welcome recommendations and/or reviews of image hosting sites, most especially those that do not presume to arbitrarily substitute photography with lossy resampling. Meanwhile, a planned migration to a new host for this website has been delayed yet again.

A virtually full resolution view of a high promontory of the Tsiolkovskiy central peak, suffering from a foreshortening affect, partly the result of simple distance and the high lateral motion of the LRO spacecraft, more 200 kilometers away. Like a more dramatic LROC NAC view of the high place on the central peaks of Tycho, this view seems to show a large boulder sitting near its top, likely a rock that emerged from the upthrust after considerable mass wasting [NASA/GSFC/Arizona State University].
Perhaps the best off-nadir view of the central peak of Tsiolkovskiy crater, prior to this latest oblique LROC NAC observation, from among the HDTV stills of the crater captured by Japan's SELENE-1 (Kaguya) orbiter in 2008. The view is from well to the north [JAXA/NHK].
Like the oblique LROC NAC mosaic of the Moon's highest elevation at Engel'gardt, discussed here in early October, this latest view of Tsiolkovskiy took place while the area of interest was under a high Sun, and from a great distance. Thus the raw result is of low contrast, the details of relief given over to raw albedo. That, and the apparent lateral motion through a field of view made small by distance, results in a less than perfect aesthetically pleasing result. We will take what we can get before continuing with the work of putting together raw illustrations needed to offer posts about the LUNAR landing site study.

Another 'full-resolution' first look at the new Tsiolkovskiy central peak NAC mosaic, this section near the southern base, a good illustration of the affects of foreshortening, and lateral speed through a narrow window, and over a bright Sun-Subject-Spacecraft phase angle. Though their trails are not individually seen, the subject and scene shown above are near to the area shown at much higher resolution (from overhead) discussed in the LROC Featured Image post "Weaving boulder trails on the Moon," last July 11 [NASA/GSFC/Arizona State University].
Sample Posts regarding Tsiolkovskiy crater:

The Old and the Young at Tsiolkovskiy (October 31, 2012)
Weaving boulder trails on the Moon (July 11, 2012)
Bulging wrinkles at Tsiolkovskiy (January 11, 2010)
Regolith on Basalt (January 10, 2012)
Highland-Mare boundary of Tsiolkovskiy (September 29, 2011)
The Hummocks of Tsiolkovskiy (August 26, 2010)
More of Tsiolkovskiy's boulders and boundaries (August 26, 2010)
Small fractures in the mare floor of Tsiolkovskiy (August 25, 2010)
Tsiolkovskiy - Constellation Region of Interest (May 1, 2010)
Uplift, Boulders of Tsiolkovskiy (September 1, 2009)

No comments: