Friday, September 30, 2011

LROC: Farside Impact!

A young, fresh impact into the farside highlands, south of Tsiolkovskiy crater. LROC Narrow Angle Camera (NAC) observation M159073200L, LRO orbit 8576, May 3, 2011; image field of view is roughly 325 meters wide. See the full size LROC Featured Image HERE [NASA/GSFC/Arizona State University].
Lillian Ostrach
LROC News System

Young impacts abound on the Moon, and the LROC NAC images of beautiful crater morphologies, spectacular ejecta blankets, and stunning impact melt deposits are enough to make any lunar geologist jump for joy. Many times, fresh impacts into mare material are featured because these craters punch through the thin layer of regolith and produce boulders. However, impacts into the lunar highlands can be just as spectacular.

Today's Featured Image of an unnamed Copernican-aged crater (~630 m diameter, 29.73°S, 134.07°E) is one such example on the farside. Close-up, the crater is bowl-shaped with a well-defined circular rim. At the crater floor center is a small, bouldery pond of solidified impact melt. Debris from the crater walls have slumped toward the floor center, but whether these slumps happened immediately after crater formation or yesterday is difficult to determine. 

The first in a brief series of reduced views of a relatively small fresh impact crater near the southwestern rim of the far more ancient 61 km-wide crater Subbotin, in the Farside lunar Highlands [NASA/GSFC/Arizona State University].
Take a look at some of the material nearest to the crater floor; in the crater center, some slumps are veneered with impact melt but other debris piles superpose (overlie) these veneered materials. These stratigraphic relationships can be used to interpret the relative ages of the slumps - the impact melt-covered piles formed soon after impact because they are splashed with impact melt, and the overlying debris piles happened after the impact melt solidified (maybe even yesterday!). Furthermore, the ejecta blanket closest to the crater rim is mostly uniform in reflectance but there are scatterings of boulders and lower-reflectance impact melt streamers that were thrown out of the crater during ejecta emplacement. 

What a beauty! 

A further reduced-resolution view from M159073200L, showing a 2.7 km field of view. See the full-size LROC context image HERE [NASA/GSFC/Arizona State University].
LROC WAC monochrome (566nm) mosaic of the Farside west of Subbotin crater swept up over the course of LRO orbits 4924 through 4926, July 20, 2010. The fresh impact crater in the opening image the small "bulls eye" just left of center in the image above. At this illumination incidence angle, ~72.7° from the west north west, the deeper central circular floor of the crater is already deeply shadowed in the coming sunset.  [NASA/GSFC/Arizona State University].
What other exciting geologic features do you observe when you explore the full LROC NAC image?

Related Posts:
Small crater at the southern rim of Menelaus
Smooth floor in Copernicus crater

Thursday, September 29, 2011

Descent of Apollo 11, DAC film compared with LROC NAC using Google Earth lunar digital elevation model

HT to Phil Platt and Scott Hall, Uploaded to YouTube by May 26, 2011.
"You can download my Google Moon KMZ file for import into Google Moon HERE," GTP writes. And "here is the link to my Apollo web site:"

"Footage from the Eagle's movie camera has been matched to deconvolved and/or enhanced versions of Lunar Reconnaissance Orbiter image M116161085 (left and right NAC image pairs) which were taken by the LRO on December 22, 2009. Google Moon does not have a roll angle feature which would be useful for rolling the point of view. Additionally, Google Moon's digital elevation model is not of a fine enough resolution in order to precisely model the terrain. Thus some of the Google Moon screen captures of the overlaid LRO image may not precisely match the view from the Eagle's video camera."

LROC: Highland-Mare Boundary of Tsiolkovskiy

Central segment from HDTV still returned by Japan's lunar orbiter Kaguya (SELENE-1, 2007. This oblique, long-range view across the craggy expansive floor and central peak from the north shows Tsiolkovsky crater's floor. It's prominent on the farside because such dark features are far fewer here than on the Nearside. The slumped inner circumference of Tsiolkovsky's rim glowers several kilometers over its floor, an area where the Naval Research Lab, MIT and NASA hope one day to eventually deploy a radio array shielded from man-made interference. Such a facility could probe the cosmological "Dark Ages," a poorly understood 200 million year-long time between the Big Bang and the formation of earliest stars and galaxies.

LROC used it's Narrow Angle Camera (NAC) to study the contact boundary between rugged highland and Tsiolkovsky's relatively flat and darker floor. (The area shown in a Featured Image released September 28, 2011 is indicated by the yellow arrow) [JAXA/NHK/SELENE].

The mare plain of Tsiolkovsky stood out plainly in the first images of the lunar Farside returned by the Soviet probe Luna 3 in 1959, highlighting from the start the striking differences between the familiar features of the Moon's nearside and an entire hemisphere never before seen by human eyes. The northeastern contact area highlighted below in a more detailed look at this part of the LROC WAC 100 meter resolution Global Mosaic is boxed in yellow [NASA/GSFC/Arizona State University].

Northeastern portion of Tsiolkovsky crater, highlighting the boundary between mare and the highlands. Asterisk notes location of NAC inset; LROC WAC monochrome mosaic, 100 m/pixel. View the full-size LROC image released September 28, 2011 HERE [NASA/GSFC/Arizona State University].

Lillian Ostrach
LROC News System

Tsiolkovsky crater is a stunning example of a complex crater and is located on the farside (185 km diameter; 20.46°S, 129.06°E). Many geological features are observed within and around this impact crater, including a central peak, terraced walls, extensive ejecta, and a partially mare-filled floor. Tsiolkovskiy is an experiment in mare basalt flooding that is frozen in time and contains one of only a few mare deposits on the lunar farside. When we usually think of mare basalts, we mentally picture the vast nearside basalts, probably because we see them so clearly during a full Moon. These nearside basalts fill (or just nearly fill) the large impact basins that formed early in the Moon's geologic history, but the basalts that flooded Tsiolkovsky (as well as those that formed Mare Moscoviense and Mare Orientale, for example) only partially flooded these farside basins. Thus, we can use these basins to study the geology of the farside mare deposits and the timing and extent of volcanism on the lunar farside.

Because substantial lateral mixing of materials on the Moon is limited, the boundary between the mare and the highlands within Tsiolkovskiy crater is particularly obvious. In the opening image, the high-reflectance highlands material in which Tsiolkovskiy formed is embayed by the lower-reflectance mare basalt. The area of the crater floor flooded by basalt is smooth and has low reflectance while the central peak, crater walls, and portions of the floor remain relatively unchanged except for the accumulation of small impacts (meters to ~5 km diameter) over geologic time.

Full 60 centimeter per pixel resolution close-up of LROC Narrow Angle Camera (NAC) observation M159100547R. LRO orbit 8580, May 3, 2011, showing a small part of the the boundary between mare and highland material in Tsiolkovsky. Instead of an obvious contact boundary between these units the change from highland to mare is gradational at this scale. The degraded crater at center has served as a slope trap for high-reflectance material that originated from the high crater wall, well outside this field of view of only roughly 350 meters. View the 600 meter-wide original LROC image HERE [NASA/GSFC/Arizona State University].

However, the boundary between the highlands and the mare in Tsiolkovsky is not so well defined at 60 cm/pixel in the LROC NAC images. Why is this the case? To answer, we must consider the way material moves on the Moon. Earlier we said that substantial lateral mixing on the Moon is limited, which is true. Impacts excavate material that is moved laterally, thus mixing local materials. With enough impacts, the albedo differences between highlands and mare will blur and eventually disappear. The fact that we see rays extending out long distances from Copernican-aged impacts show that lateral mixing occurs over great distances. So why can we still see the highlands-mare boundary so sharply in the WAC images? Close examination of that same boundary in the NAC images shows the boundary to be not so sharp. At the scale of the NAC, you can see that impact cratering is slowly blurring the boundary. Have you experienced this effect in your travels here on Earth? Perhaps you have planned an adventure using a geologic map or a map based on satellite images or airplane photography only to find that the well-defined boundary you noticed on the map is not so easy to spot on the ground. If you haven't, well, perhaps it is time to plan your next adventure!

Prowl around the mare-highlands boundary in Tsiolkovsky crater in the full LROC NAC image!

Related Posts:

Wednesday, September 28, 2011

Scarps in Schrödinger

A lobate scarp formed in the wall material of Schrödinger basin. LROC Narrow Angle Camera (NAC) observation M159099396R, LRO orbit 8580, May 3, 2011, field of view 1.1 km, illumination from the extreme northeast, within 75° of the lunar south pole. View the full-sized LROC Featured Image HERE [NASA/GSFC/Arizona State University].

Lillian Ostrach
LROC News System

Surface manifestations of contractional stresses are observed frequently on the Moon. Oftentimes, wrinkle ridges (from several tens of meters to many hundreds of kilometers long) formed in maria are the most easily identified contractional tectonic features. Another geologic feature resulting from contraction, lobate scarps, are observed in the highlands. From LROC NAC images we now know that lobate scarps are prevalent in the highlands and thus are globally distributed. The Lee-Lincoln scarp and a lobate scarp in Slipher crater are excellent examples of highland scarps. Today's Featured Image reveals a lobate scarp in the Schrödinger basin (79.30°S, 126.50°E), an example smaller than the Lee-Lincoln and Slipher crater scarps.

Lobate scarps are the surface expression (visible part) of a fault that cuts through the lunar crust. In the opening image, the crust was probably under compression from approximately north to south (squeezed from top to bottom). The ground on the northern part of the image buckled, broke, and rode up over the ground on the southern part of the image, creating the obvious bulge. Also, just like faults on Earth, the scarp shallows out and disappears (near the right of the image). This shallowing of the scarp may be due to non-uniform contractional stresses in this area such that the stresses were not the same everywhere. Alternatively, the underlying rocks may have had different strengths, which caused the stresses to deform the rocks differently. The story is further complicated here because the scarp formed in the impact basin wall material, which was likely heavily fractured and fragmented during the violent, basin-forming impact. This scarp is ~1.3 km long and may extend for several hundred meters or more beyond the western edge of the NAC frame. While this scarp shallows and disappears, the full NAC image includes portions of at least two additional nearby lobate scarps. The scarp formation story is not a simple one, and additional observations are necessary to piece together the compressional history of this area.

From the LROC Wide Angle Camera (WAC) monochrome 100 meter per pixel resolution global mosaic, showing the southern frontier of the Schrödinger impact basin. A twenty kilometer stretch, running from southwest to northeast, is the location of a plethora of lobate scarps. The location of the lobate scarp highlighted in the LROC Featured Image released September 27, 2011 is noted with a yellow arrow [NASA/GSFC/Arizona State University].

Wider angle segment from the WAC 100 meter global mosaic, showing the full width of Schrödinger basin. The location of the lobate scarp highlighted in the LROC Featured Image released September 27, 2011 is noted with a yellow arrow [NASA/GSFC/Arizona State University].

How many lobate scarps can you find in the full LROC NAC image? Do these scarps intersect or are they separate from one another?

Related Posts:
LOLA: Schrödinger Basin
A Review of All Things Schrödinger
Wrinkled Planet
Aitken Crater Constellation Program ROI
Sampling Schrödinger

From LOLA data, Schrödinger basin in relation to the far lunar south and within the degraded mountainous rim of the vast South Pole Aitken basin. Once again, the location of the area highlighted in the LROC Featured Image released September 27, 2011 is indicated with a yellow arrow [NASA/LOLA/ILIADS].

Tuesday, September 27, 2011

The First Race to the Moon

Engineer Special Study of the Surface of the Moon (1960, 1961), "Generalized Photogeologic Map of the Moon" (Robert J. Hackman, USGS; Prepared for the Office, Chief of Engineers, Department of the Army, U.S.) [LPI, USGS].
David S. F. Portree
Beyond Apollo

The race to the moon began on August 17, 1958, and the Soviet Union won. This isn't the opening line of an alternate history story; rather, it is an acknowledgment that more than one moon race took place. The first, with the goal of launching a small automated spacecraft to the moon, began with the liftoff of the Able 1 lunar orbiter, a 38-kilogram U.S. Air Force (USAF) probe. (It was later redesignated Pioneer 0.) Just 77 seconds after launch from Cape Canaveral, Florida, Able 1's first-stage Thor rocket exploded, ending the world's first attempted lunar mission.

A month later, on September 23, 1958, the Soviet Union joined the race. A spherical Luna probe intended to impact the moon fell victim to the failure of its upgraded R-7 booster rocket just 93 seconds after liftoff from Baikonur Cosmodrome in central Asia.

On October 11, 1958, USAF launched Able 2, a near-copy of Able 1. It was the first lunar launch conducted under NASA auspices. The civilian space agency had opened its doors on October 1, 1958. NASA absorbed most Department of Defense space projects, though in practice the USAF and Army continued to carry out missions while interagency relations and lines of command became defined. Able 2, later redesignated Pioneer 1, burned up in Earth's atmosphere on October 13, after its Able second stage shut down early, placing it on an elliptical path that took it about a third of the way to the moon. The Soviets launched their second Luna moon impactor just 16 hours after the U.S. launched Able 2. The Luna's upgraded R-7 launch vehicle exploded 104 seconds after liftoff.

And so it went, with launches from Florida and Kazakhstan alternating and failing.

Read the Remarkable Chronicle HERE.

Friday, September 23, 2011

Arkansas Apollo 17 commemorative lunar sample found packed away among Bill Clinton's files

Diane Alter

A long lost, highly valuable moon rock, bought back by Apollo 17 has been found in former U.S. president Bill Clinton's files.

The rock, missing for 30 years, was one of 50 presented to each state after the 1972 space mission. It was presented to Clinton's predecessor Gov. David Pryor in 1976. The rock hung in the governor's office that was later occupied by Clinton. The rock was apparently packed away with Clinton's memorabilia after it fell off its plaque.

The moon rock is estimated to be worth $10 million. NASA says that few of the rocks, which were encased in acrylic and mounted on a plaque with the intended recipient's flag, can be located.

The rock has been missing since 1980. Reports are that the rock fell off the plaque and was mistakenly packed away with gubernatorial papers belonging to Clinton. The archivist knew exactly what is was when he stumbled upon it.

Three months after Apollo 17 returned home, then-president Richard Nixon ordered that fragments of the rocks carried home by astronauts Eugene Cernan and Harrison Schmidt be distributed among 135 foreign heads of state, the 50 U.S. states and its territories. When presented to the states as gifts, they became property of the state they were donated to. Only 60 can be located. The rest are said to have been stolen or lost.

The rock is currently safely stored in a library safe.

NASA posts Global Exploration Roadmap

"Small pressurized rovers on the moon will increase crew mobility and can be reused at different landing sites." A familiar notion, as envisioned by the International Space Exploration Coordination Group in their "The Global Exploration Strategy: The Framework for Coordination," developed by the 14 national space agencies. The study presents an International road map with a similarly familiar fork in the road ahead, two decidedly different directions beyond low Earth orbit, Asteroid Next and Moon Next [NASA/ISECG].

Michael Braukus
J.D. Harrington
NASA Headquarters

NASA is releasing the initial version of a Global Exploration Roadmap (GER) developed by the International Space Exploration Coordination Group (ISECG). This roadmap is the culmination of work by 12 space agencies, including NASA, during the past year to advance coordinated space exploration.

The GER begins with the International Space Station and expands human presence throughout the solar system, leading ultimately to crewed missions to explore the surface of Mars.

The roadmap identifies two potential pathways: "Asteroid Next" and "Moon Next." Each pathway represents a mission scenario that covers a 25-year period with a logical sequence of robotic and human missions. Both pathways were deemed practical approaches to address common high-level exploration goals developed by the participating agencies, recognizing that individual preferences among them may vary.

To view the document, visit: or click on the link in the first paragraph above.

ISS: Earth's Moon

Photographed by the Expedition 28 crew aboard the International Space Station, this image shows the moon, the Earth's only natural satellite, at center with the limb of Earth near the bottom transitioning into the orange-colored troposphere, the lowest and most dense portion of the Earth's atmosphere. The troposphere ends abruptly at the tropopause, which appears in the image as the sharp boundary between the orange- and blue-colored atmosphere [NASA/ISS].

Michael J. Drake

Christopher Francis
KOLD 13 Tuscon

University of Arizona professor Michael J. Drake, who helped guide the growth and prestige of the university's Lunar and Planetary Laboratory, has died at the age of 65.

Drake passed away at the University of Arizona Medical Center-University campus, according to a campus statement.  Drake was a Regents' Professor and director of the LPL as well as head of the department of planetary sciences.

Drake joined the UA planetary sciences faculty in 1973.  He had headed LPL and the planetary sciences department since 1994.  When he arrived, the lab was much smaller, occupying only a part of what is now the Kuiper Space Sciences Building.

View the regional television coverage HERE.

From the University of Arizona at Tuscon:

Michael J. Drake, Regents' Professor, director of the University of Arizona Lunar and Planetary Laboratory and head of the department of planetary sciences, died Wednesday at The University of Arizona Medical Center-University Campus in Tucson, Ariz. He was 65.

Drake, who joined the UA planetary sciences faculty in 1973 and headed LPL and the planetary sciences department since 1994, was the principal investigator of the most ambitious UA project to date, OSIRIS-REx, an $800 million mission designed to retrieve a sample of an asteroid and return it to Earth. OSIRIS-REx is due to launch in 2016. It is the largest grant or contract the UA has ever received.

Drake played a key role in a succession of ever more high-profile space projects that garnered international attention for LPL and the University.

Those include the Cassini mission to explore Saturn, the Gamma-Ray Spectrometer onboard NASA's Mars Odyssey Orbiter, the HiRISE camera onboard NASA's Mars Reconnaissance Orbiter and the Phoenix Mars Lander.

Drake also was a Fellow of the American Geophysical Union, the Geochemical Society and the Meteoritical Society, and he was president of the latter two. He was awarded the Leonard Medal, the highest prize of the Meteoritical Society, in 2004, in part for his work connecting the HED meteorites to the asteroid 4 Vesta.

A native of Bristol, England, Drake graduated with a degree in geology from Victoria University in Manchester, and then he left for a doctoral program in geology from the University of Oregon, graduating in 1972. After a postdoctoral program at the Smithsonian Astrophysical Observatory, Drake moved to, and immediately fell in love with, Arizona.

As a young assistant professor, Drake joined a much smaller LPL in 1973. The lab occupied only a part of what is now the Kuiper Space Sciences Building, and most of his colleagues came from astronomy. Planetary sciences did not have the cachet then that it does now.

"It was, from my point of view, a strange environment," Drake wrote earlier on LPL's website. "It's like the Tower of Babel; you talk in your own language and your own jargon, and communicating across fields is surprisingly difficult. It took a few years before I think most of us began to understand what motivated the other ones, what we were really saying. I think it helped us to speak in clearer, plain English and minimize the jargon, because we came from such  different backgrounds."

Regents' Professor Peter Strittmatter, who recently retired as director of the UA's Steward Observatory and head of the UA astronomy department, said Drake used those communication skills to expand LPL and form close relationships with NASA.

"Mike thought and spoke clearly so you always knew where he stood on an issue," Strittmatter said. "He was a superb director of LPL, a great leader and a great personal friend. He will be sorely missed by all of us at the University of Arizona and especially those involved in the space sciences."

Peter Smith, the principal investigator for the Phoenix Mars Lander mission, said he began working with Drake when Smith was building the camera for the 1997 Mars Pathfinder. He called Drake's handling of the complexities of proposal development "masterful."

"We would meet monthly to review progress and plan strategy," Smith said. "Mike always encouraged excellence and made sure that the University was providing full support to our programs. Over the years, as my career progressed through various missions to Mars, he was there when troubles surfaced and a political push was needed," said Smith, who is also part of the OSIRIS-REx mission.

"He watched our flight projects from the sidelines; his enthusiasm made it clear that he wished for a more direct involvement. After winning the project of his dreams, Mike will continue to inspire and lead through the legacy of his accomplishments."

Edgar J. McCullough, retired professor and head of the UA geosciences department and dean of the College of Science, said he and Drake became friends in the early 1970s when they would go on week-long backpacking excursions around the West.

"When he was in planetary sciences and I was head of the geosciences department, we set up a microprobe laboratory with funding from both departments. It was the first big piece of diagnostic equipment here at a time when geoscience was becoming more of an analytical science," McCullough said. "He was the kind of faculty member you wanted because he was also strong on teaching, especially undergraduates."

McCullough said Drake helped develop promotion and tenure policies for the college and was instrumental in establishing a joint position between the colleges of science and education to create science education programs. Drake also led a major undergraduate teaching effort in planetary sciences, even though the department was created as a graduate program.

Joaquin Ruiz, executive dean of the Colleges of Letters, Arts and Science, said: "Mike was a distinguished scholar, an accomplished administrator and a good friend. His students loved him for his energy, smarts and care. He was able to run the department of planetary sciences incredibly smoothly at the same time as he was writing significant papers about the early evolution of the Earth and solar system and still have time to successfully compete for OSIRIS-REx."

Timothy Swindle, the assistant director at LPL, summed it up, saying, "Not only was he a world-class scientist, but he was a tireless advocate for the Lunar and Planetary Laboratory and all the people who have worked here. Personally, he was a friend and mentor for me, and for many others, and we will miss him deeply."

via Daniel Stolte
University Communications
University of Arizona

and Timothy D. Swindle
Professor, Planetary Sciences and Geosciences
University of Arizona

Moon over Kandahar

From Lunar Pioneer 7

21 September 2011
Zhari District, Kandahar Province, Afghanistan
Task Force Spartan, 4-4 Cav

"The moon in September was special and the war kept going."

via "Every Step is Your Last"
Michael Yon - Online

O Afghanistan,
Save us from Babylon.
If they can take your name away
Can't they take ours too?
If they can take your name away
Can't they take our too?"

Firesign Theater
"Fighting Clowns" (1980)

LROC: A Gathering in Lacus Mortis

Boulders meet in a valley amidst central peaks of Bürg crater (45.0°N, 27.2°E). LROC Narrow Angle Camera (NAC) observation M111415328L, LRO orbit 1553, October 29, 2009; incidence angle 51.7°. Sun is from the south-southeast, north is right, image resolution 49 cm per pixel. View the full size LROC Featured Image HERE [NASA/GSFC/Arizona State University].

James Ashley
LROC News System

Clear impressions in the lunar soil show paths that boulders followed as they rolled downhill in the mountains surrounded by Lacus Mortis (the Lake of Death). If you look closely, you can see trails from both the top and bottom of this image. Also the trails are in some cases jagged -- not orderly, straight lines. What caused such striking patterns?

As is often the case, close inspection of a broader area reveals what we are seeing. Knowledge of the local topography and an understanding of the effects of gravity provide the explanation: The boulders rest in a valley present within the double central peak of Bürg crater. They rolled down from the bouldery summits of opposing slopes and accumulated along the valley floor. The largest block is approximately 23 meters in long diameter!

Note the tortuous paths of some of these boulders. These paths are the results of slow movement combined with irregular shapes (have you ever tried to roll a football in a straight line?). The straighter paths probably represent more rapid movement because the momentum of a faster-moving body helps it maintain its path of travel. Notice that at least one of them bounced along the slope, making impressions only when it touched the surface. Other boulders never made it all the way to the bottom of the slope. Still others don't seem to have clear traces in the regolith up-slope from their location. How could this be? Is it safe to say that some of these arrived more recently than others? Why or why not? Hint: How rapidly does the lunar regolith get reworked by micrometeorite impacts, and how quickly should such gardening erase traces like these?

The 6700 meter high rims and terraced interior walls of 41 km-wide Bürg (45.0°N, 28.2°E), from a 100 m/p resolution LROC Wide Angle Camera (WAC) mosaic, shows the Featured Image location between the central peaks. See the full size context image HERE [NASA/GSFC/Arizona State University].

Lacus Mortis is shown in the WAC mosaic (below), this area is visible through the eyepiece of a small, backyard telescope beginning with the late waxing crescent phase, about 6 days past new Moon (See the last image in this post for the telescopic view from Earth during a favorable libration in April 2010). If you can find Bürg crater, then you'll see where the Featured Image is located, even though the details of the crater will be far too small to see.

WAC mosaic (from the Web Map Server LROC image search) of Lacus Mortis and environs. See the original, more detailed LROC context image HERE [NASA/GSFC/Arizona State University].

Explore the full NAC frame here. Another post featuring the complexities of Bürg crater can be found here. Related Featured Image posts also include Sampling Schrödinger; Tycho Central Peak Spectacular; and Boulder in Recht crater.

Explore the full NAC frame HERE. Another post featuring the complexities of Bürg crater can be found HERE. Related Featured Image posts also include Sampling Schrödinger; Tycho Central Peak Spectacular; and Boulder in Recht crater.

Lacus Mortis is a familiar Nearside landmark, between Mares Serenitatis and Frigoris, well situated for locating nearby large craters and vice versa. It is less spectacular but just as unusual in this false-color image from LOLA altimetry, a continuum of most of the Nearside's below-lunar mean elevations. It is a place now confirmed that hosts deep faults and volcanism  [NASA/GSFC/MSFC/LOLA/LMMP].

The View from Earth: This small section from an global lunar mosaic by Astronominsk demonstrates Lacus Mortis is easier to see during a libration favorable enough to swing Mare Humboldtanium into view. A small host of quick-study neighborhood landmarks are all easy to locate in a small telescope [Astonominsk].

Still more related posts:
Rimae Bürg
Not your average complex crater
Lunar morphology in the lake of death
Blogger's Best for the Best
Terraced Wall of Bürg

Thursday, September 22, 2011

International Observe the Moon Night, October 9

"International Observe the Moon Night has created the opportunity to for people to take notice of the Moon’s beauty and share that experience with one another. Through International Observe the Moon Night, we hope instill in the public a sense of wonderment and curiosity about our Moon. Our partnerships enable us to stay up to date with the latest and greatest scientific discoveries about Earth’s nearest neighbor, and we strive to bring those discoveries to the public."

Visit the official Website HERE.

On the shore of the Bay of Rainbows

A pair of small craters show different albedos within a spectacular ejecta display along the shore of Sinus Iridum (47.9°N, 31.7°W). LROC Narrow Angle Camera (NAC) observation M104726204L, LRO orbit 591, August 12, 2009; incidence angle 65°, Sun is from the southwest, resolution 1.71 meters per pixel (Field of view < 1 km). View the full size LROC Featured Image HERE [NASA/GSFC/Arizona State University].

James Ashley
LROC News System

In addition to being a spectacular example of a recent impact feature, this pair of small craters was chosen with the small backyard telescope in mind. You won't be able to see this impact feature in your eyepiece, but you should be able to locate the region fairly easily. By the 11th day following a new Moon (during the waxing gibbous phase), Sinus Iridum (the Bay of Rainbows) is ideally illuminated and visible through even a modest-sized instrument, or even a large pair of binoculars! Look for the large, crescent-shaped arc of mountains on the northwest "shore" (44.1°N, 328.5°E) of Mare Imbrium. You will find the partial remains of an ancient crater (236 km diameter), flooded long ago by Mare Imbrium basalts. The range of peaks is known as the Jura Mountains. With a good eye, you might even see the crater Bianchini, nestled within the range along its northwestern edge. You can use Bianchini with the images below to pinpoint the Featured Image location.

This wider view from M104726204L shows foothills high, mountainous rim of Sinus Iridum, immediately to the north, more than 2 km higher in elevation than the wide bay floor to the south. Note how the ejecta rays were forced to curve as the flying debris encountered the topography just northeast of the larger and more recent impact (field of view ~8.3 km across, downsampled to 2.8 meter/per pixel). See the spectacular full size LROC context image HERE [NASA/GSFC/Arizona State University].

Notice how one of the featured craters has a low-reflectance interior while the other appears more reflective. The low-reflectance crater is roughly twice the size of the light-floored crater, and therefore excavated to a greater depth. Could this have resulted in the exposure of darker, buried materials that were missed by the less-energetic impact? There are many questions that we could ask about this interesting pair: Which impact happened first? Is there ejecta from one crater on the floor of the other? Why or why not? 

What other clues would you look for in the full NAC frame?

The 39 km-wide crater to the upper left of the Featured Image location (yellow arrow) is Bianchini in this LROC Wide Angle Camera (WAC) mosaic showing a roughly 300 km field of view. See the richer, original LROC WAC context image HERE [NASA/GSFC/Arizona State University].

Related posts include:
Dark-haloed crater in Mare Humorum
Dark-haloed crater near Censorinus A
Sinus Iridum - Next Destination?

Wednesday, September 21, 2011

LPI: Postdoctoral Researcher in Petrology of Planetary Materials

The Lunar and Planetary Institute (LPI), part of the Universities Space Research Association (USRA), invites applications for a postdoctoral fellowship in the petrology of planetary materials.

The successful candidate will work with Dr. Allan Treiman in NASA-funded efforts, focusing on planetary crusts and magmas, and their volatiles constituents; target materials include lunar highlands rocks, Martian meteorites, and terrestrial analogs. These efforts focus on planetary samples, starting with analyses by optical microscopy and electron microprobe; other instruments are available at nearby Johnson Space Center or with external collaborators. The candidate will be encouraged to design and conduct their own research in planetary science, propose for external funding, participate in grant review panels and analysis groups, and become involved with spacecraft missions.

The successful candidate will have a recent Ph.D. in petrology or geochemistry; experience with planetary materials is helpful, but not required. The position would be for two years, with possible extension to a third year. Review of candidates will begin on November 15, 2011, with a hiring decision as soon as possible thereafter. Further information can be found on our website:

The Universities Space Research Association is an Equal Opportunity Employer.

GRAIL: Postdoctoral position, planetary geophysics

The Institut de Physique du Globe de Paris (IPGP) is inviting applications for a postdoctoral position in the field of planetary geophysics. This two year position aims to support the analysis of lunar gravity data that will be obtained by NASA's mission GRAIL (Gravity Recovery and Interior Laboratory). Possible research topics include the study of lunar impact craters, volcanic landforms, and the structure and evolution of the lunar crust.

Following a successful launch on September 10, 2011, a start date in early 2012 is expected. To apply, please provide a CV, publication list, contact information of two references, and a 2-page letter that motivates the envisioned research project and that describes the applicant's research interests. Multidisciplinary research projects that combine GRAIL-derived gravity data with other remotely sensed data sets will be favored.

Please respond by email to Mark Wieczorek ( before October 15.
Mark Wieczorek
Equipe Géophysique Spatiale et Planétaire
Institut de Physique du Globe de Paris

Accompanying Visual HERE.

Tuesday, September 20, 2011

LROC: Dark wisps along the rim of Copernicus

Dark streaks ornament a slope along the Copernicus crater rim (9.3°N, 21.5°W). Down-slope is to the right. LROC Narrow Angle Camera (NAC) observation M11735067L, LRO orbit 1600, November 1, 2009; incidence angle 32°, Sun is from the east, north is up, field of view is roughly 400 meters across. View the full size LROC Featured Image HERE [NASA/GSFC/Arizona State University].

James Ashley
LROC News System

What are these low-reflectance (dark), wispy streaks? The differences in color among lunar deposits is often understood in terms of composition and/or intensity of space weathering (which can discolor soils over time). When they become mixed (often from cratering events), they can produce areas of high color contrast. Most of them seem to have the lowest reflectance at the points highest in elevation on the crater wall (to the left), and become more reflective down-slope (to the right). The features in this image seem to cluster near a promontory that has its own streak of material, emanating as a fan-shaped curtain (see context image below).

From a wider view of LROC NAC M11735067L, showing the association of a promontory's location with the occurrence of the dark deposits (See next image). Field of view roughly 2.2 km across (downsampled from 50 cm/pixel to approximately 2.3 meters/pixel. View the full size LROC context image HERE [NASA/GSFC/Arizona State University].

An artificial perspective of the massive slumped inner slope of the east rim of Copernicus made possible by NASA's ILIADS program. The topography represents laser altimetry collected by LOLA overlaid with morning Terrain Camera imagery from Japan's lunar orbiter Kaguya. (The LROC Featured Image is a close up from overhead of the slot in the crater rim, left of upper center.) View a HDTV orbital still showing Copernicus HERE [NASA/GSFC/MSFC/JAXA/SELENE].

There are several possible explanations for how the smaller, low-reflectance features formed. For example, these dark patches may represent mare basalts that were buried and re-exposed by the formation of Copernicus and subsequent mass wasting. Another possibility is that the low-reflectance materials are dikes or sills (intrusive igneous bodies) that pre-date the Copernicus impact and are now weathering out. Still a third possibility is that mare basalt debris were ejected by a nearby impact and deposited here, perhaps encouraging the erosion of the promontory in the process - or landing near the promontory by coincidence. In this later scenario, each block of ejecta might then have fragmented upon impact and migrated down-slope as individual debris aprons. There are several nearby, relatively recent craters outside of the Copernicus rim that could be responsible for this type of deposition. Are there any additional clues that could be looked for to further solve this mystery?

A 54.6 meter per pixel LROC Wide Angle Camera (WAC) perspective centered on the area of interest, on the west-southwestern rim of Copernicus. LROC WAC M131793087C (604 nm), LRO orbit 4556, June 21, 2010; little more than a day after local sunrise, incidence angle 82.2° [NASA/GSFC/Arizona State University].

Above, the LROC WAC context image showing the expanse of Copernicus provides a sense for how steep the outermost walls of the 95 km-wide crater are, and the location of area highlighted in the Featured Image released September 20, 2011. View the full size LROC WAC context image HERE [NASA/GSFC/Arizona State University].

Review the full NAC image HERE to look for more examples.

Related posts:
Dark streaks in Diophantus crater

Monday, September 19, 2011

A mission to find the missing lunar module

Tom Stafford and Gene Cernan in the Apollo 10 lunar module "Snoopy" prepare to dock with John Young, who snapped this picture on May 23, 1969. Away only eight hours Stafford and Cernan put the LM into a transfer orbit and descended to 14.4 km above the lunar surface before dropping the landing stage and firing the critical ascent stage six subsequent missions would depend upon to return them to ferry them back the Command Module and eventually to Earth. It was only the second time humans had visited the Moon's vicinity less than two months before Apollo 11. When later Jettisoned, the LM ascent stage engine was ignited remotely, on a trajectory placing the vehicle in orbit around the Sun, where it is presumed to remain to the present day. "Snoopy" is the only intact LM ascent stage remaining of the ten full Apollo lunar landers eventually launched into space [NASA/JSC].

Adrian West
Universe Today

Where is the Apollo 10 Lunar capsule? It’s somewhere out there — orbiting the Sun — and there’s a new initiative to try and find it!

The Apollo 10 mission launched on May 18, 1968 and was a manned “dry run” for its successor Apollo 11, testing all of the procedures and components of a Moon landing without actually landing on the Moon itself.

After carrying out a successful lunar orbit and docking procedure, the Lunar Module (called “Snoopy”) was jettisoned and sent into an orbit around the Sun.

After 42 years, it’s believed to still be in a heliocentric orbit and a team of UK and international astronomers working with schools are going to try and find it.

Read the full story HERE.

Let's argue about the right things.

President Theodore Roosevelt's "Big Stick," displayed in the form of sixteen gleaming modern battleships with 14,000 sailors that soon became known as "The Great White Fleet." Over 1908 it was a substantive pageant that circled the world, making 20 ports of call and signaling America's arrival as a world power.

Paul D. Spudis
The Once & Future Moon
Smithsonian Air & Space

We seem to be in one of those periods in which basic reasons for doing what we do as a nation are called into question.  This includes our national civil space program, which for the last few years has engaged in an extended period of back-biting and navel-gazing.  Much of this “debate” has focused on either or both of two points: what rocket to build and where to go, and not on sustainability.

In an era of limited resources, our challenge is to create a worthwhile space program with an expenditure rate that falls at or below a level perceived as affordable.  Given this reality (regardless of prevailing agency direction or assertions about projected deep space destinations) it is highly likely that cislunar space will be the sphere of space operations for the coming decade or two. Thus the questions should be:  What are we doing in space and why are we doing it?  If the answer is a series of space exploration “firsts” (flags-and-footprints forever), that model will require specific activities and missions.  If the answer is that an incrementally developed transportation infrastructure is desired, one that creates an expanding sphere of human operations, then such a model requires a different set of specific activities and missions.

Thus, the real debate is not about launch vehicles or spacecraft or even destinations; it is about the long-term – the paradigm or template of space operations.  One model requires mega-rockets to distant targets for touch-and-go missions; for convenience, I’ll call it the “Apollo” template (no denigration intended).  The other model is an incremental, go-somewhere-to-stay-and-then-expand-onwards mindset – call it the “Shuttle” template (again, same disclaimer).  The one that you adopt and follow depends on what purpose you believe human spaceflight serves.

Because Mars may harbor former or existing life, NASA has presumed that it is our “ultimate destination” in space.  In effect, the entire focus of the human spaceflight effort has devolved into a huge science project – “The Quest for Life” (which means finding pond scum, not ET).  Thus, debate about what to build, where to go and how to do it must be formulated towards attainment of Mars.

This unspoken assumption has been at the root of most space objective studies for the past 20 years.  Mars was the end point of President George H.W. Bush’s Space Exploration Initiative, President George W. Bush’s Vision for Space Exploration, of former Lockheed-Martin President Norm Augustine’s two reports, and a myriad of space groups and societies.  From the 1990′s to the present, a multi-billion dollar robotic campaign has sent mission after mission to Mars, each discovering that the red planet once had liquid water.  This mania for Mars and preoccupation with possible life there, has blinkered our perceptions of the space program and distorted our reality of what is possible or attainable on reasonable time scales with available resources.

Long term, the goal for human spaceflight is to create the capability to go anywhere we choose, for as long as we need, and do whatever we want to in space.  For the sake of argument, if one accepts such a goal, which model is more amenable to implementing it: the Apollo template or the Shuttle template?

If our goal is to “sail on the ocean of space,” we need a navy.  Navies don’t operate with just one class of ship because one class isn’t capable of doing all that is necessary.  Not all ships will look or operate the same because they have different purposes and destinations.  We need transports, way stations, supply depots, and ports.  In space terms, these consist of one to get people to and from space (LEO), one to get them to and from points beyond LEO, way stations and outposts at GEO, L-1, low lunar orbit, and to the lunar surface.  To fuel and provision our space navy, we require supply (propellant) depots in LEO, L-1 and on the lunar surface.  Ports of call are all the places we may go to with this system.  Initially, those ports are satellites in various orbits which require service, maintenance and replacement with larger, distributed systems.  Later, our harbor will be the surface of the Moon, to harvest its resources, thereby creating more capability and provisions from space.  Reliable and frequent access to the entire Solar System, not one or two destinations, should be our ultimate goal.

By designing and building mission-specific vehicles and elements, the “Apollo” template forfeits going everywhere and doing everything.  However, adopting the “Shuttle” model does not preclude going to Mars.  In fact, I contend that to go to Mars in an affordable manner that sustains repeated trips, one needs the infrastructure provided by a space faring navy.  Building a series of one-off spacecraft – huge launch vehicles to dash to Mars for expensive, public relations extravaganzas will eventually put us right back in the box we’re in now.

We have been arguing about the wrong things.  It is the mindset of the space program that needs re-thinking – not the next destination, not the next launch vehicle, and not the next spacecraft.  How can we change the discussion?  First, we need to understand and articulate the true choices so that people can see and evaluate the different approaches and requirements.  Second, we need to develop sample architectures that fit the requirements for “affordable incrementalism.”  Finally, we need to get such plans in front of the decision makers.  There is no guarantee that they will accept it or even listen to the arguments for it.  But right now, they are completely ignorant about it.

A cost-effective, sustainable human spaceflight program must be incremental and cumulative.  Our space program must continually expand our reach, creating new capabilities over time.  Moreover, it should contribute to compelling national economic, scientific and security interests.  Building a lasting and reusable space transportation system does that, whereas a series of PR stunt missions will not.  The original vision of the Shuttle system was to incrementally move into the Solar System – first a Shuttle to-and-from LEO, then Station as a jumping off platform and then beyond LEO into cislunar space.  We have the parts from the now retired Shuttle system and an assembled and working International Space Station.  We can use these legacy pieces to build an affordable system to access the near regions and resources of cislunar space.  In this new age of austerity, perhaps we will finally acquire the means to build our pathway to the stars.

Originally published September 17, 2011 at his Smithsonian Air & Space blog The Once and Future Moon, Dr. Paul Spudis is a Senior Staff Scientist at the Lunar and Planetary Institute in Houston. The opinions expressed are those of the author and are better informed than average.

Friday, September 16, 2011

Postdoctoral Research Associate Position in Lunar Petrology and Geochemistry

We invite applications for a Postdoctoral Research Associate position in lunar petrology and geochemistry in the Department of Earth and Planetary Sciences (EPS) at Washington University in St. Louis.  The primary focus of the position will be to use standard petrographic techniques to characterize lunar-meteorite breccias with the goals of constraining models of formation of the crust and modification by impacts.  Much of the work will involve mapping and analysis of thin and thick sections using our state-of-the-art JEOL JXA-8200 electron microprobe.  Opportunities exist to collaborate on investigations involving geochronology and geochemistry of lunar meteorites and Apollo samples.

Experience in the following areas is preferred:  igneous and impact petrology and geochemistry, preparation of samples for analysis, use of an electron microprobe, and use of Adobe Photoshop®.  Previous experience with planetary materials is not required.  The initial appointment will be for one year with an option to extend to two years.

Applicants should send a current curriculum vitae, including publication list, statement of research interests, and the names and contact information for three references to Dr. Randy Korotev.  

A Ph.D. in geology, planetary sciences, chemistry, or physics is required at the time of appointment.  The position will be available starting November 1, 2011, although later dates of appointment can be negotiated; the position will remain open until filled.  Women and minorities are encouraged to apply.  Washington University is an equal opportunity/affirmative action employer.

Randy L. Korotev   
Research Professor
Washington University in Saint Louis
Department of Earth & Planetary Sciences
Phone: (314) 935-5637
Fax:   (314) 935-7361

Mailing addresses:
postal service:                    
Randy Korotev                      
Washington University              
1 Brookings Dr                     
Campus Box 1169                    
St. Louis, MO 63130-4899          

Washington University
Earth & Planetary Sciences
E&PS Bldg, Room 110
St. Louis, MO 63130

LROC 7th Planetary Data System Release

Ernest Bowman-Cisneros
LROC News System

The 7th LROC Planetary Data System (PDS) release includes images acquired between 16 March 2011 and 15 June 2011. This release includes 76,516 EDR images totaling 8.6 Tbytes and 76,516 CDR images totaling 18 Tbytes worth of data.

To date, the LROC team has released to the PDS a total of 503,207 images (EDR) totaling 56.2 Tbytes. The archive can be accessed HERE.

It's the Moon's fault

Linear rille in Mare Tranquillitatis, the result of extensional stresses. What caused the offset in the rille on the east wall? LROC Narrow Angle Camera (NAC) observation M146858595LE, LRO orbit 6776, December 13, 2010, field of view 700 meters. See the full size LROC Featured Image HERE [NASA/GSFC/Arizona State University].

Drew Enns
LROC News System

Linear rilles are so named because of their nearly-straight morphology and surface expression. Unlike sinuous rilles, which are volcanic, linear rilles are tectonic in nature. Similar features on Earth are termed graben, and are created when two normal faults border a block of rock which has been depressed, producing a valley.

Since normal faults are understood to be the products of extensional stresses (see yesterday's Featured Image post), we can assume this region of the Moon was "pulled apart" - creating these normal faults, dropping the middle blocks, and producing the linear rilles. So a linear rille is the lunar analog of a graben on Earth!

Full two kilometer width segment of LROC NAC frame M146858595LE, showing the approximate location of the LROC Featured Image, September 15, 2011 [NASA/GSFC/Arizona State University].

LROC Wide Angle Camera (WAC) context images of the Rimae Sosigenes extensional linear rille system in the northeast Mare Tranquillitatis, between the Arago domes (out of view, to the south and east) and the craters Sosigenes and its smaller namesake Sosigenes A. one rille is cross-cut with a close-grouped and prominent secondary crater chain, well-known to well-equipped telescopic observers when the morning terminator passes over five days following a New Moon. WAC monochrome (566 nm) mosaic from orbits 4515-4517, June 18, 2010. See the original LROC WAC context image HERE [NASA/GSFC/Arizona State University].

In today's featured image, two normal faults appear to be offset.

What are we seeing here?

Is Mare Tranquillitatis really an impact basin? Looks can be deceiving, when comparing two familiar and neighboring basins, each flooded multiple times with volcanic flows. Dark and optically-mature regolith covers both Mare Serenitatis (top center) and Tranquillitatis (below - the area of interest is indicated with the yellow area), though the differences in color of each are obvious even in black and white photographs. But In this false-color LOLA elevation map, the nature of Mare Tranquillitatis is less obvious, until one examines more closely and sees how the weight of material infilling the Tranquillitatis plain may have led to finer features like wrinkle ridges and extensional rilles [NASA/GSFC/LOLA/MSFC/LMMP].

It is probably an en echelon step between the two normal faults making up the east wall of the rille. When two faults are near to each other, they can interact and create an en echelon step that helps to even out the displacement and forces that created the faults. En echelon steps are common, and are seen in other tectonic features on the Moon.

Can you find any more faults in the full NAC frame?

Related Posts:
Rima Bürg
Rima Ariadaeus - A Linear Rille

Wednesday, September 14, 2011

LROC: lobate scarp in Xenophanes

A North-South trending lobate scarp inside very ancient 127 km pre-Nectarian Xenophanes, showing the distinct "elephant skin" surface texture typical of lunar slopes. LROC Narrow Angle Camera (NAC) observation M118031613LE, LRO orbit 2528, January 13, 2010; resolution 60 cm per pixel, field of view 600 meters. View the full size LROC Featured Image HERE [NASA/GSFC/Arizona State University].

Drew Enns
LROC News System

Lobate scarps are long, curvilinear structures found on some planetary bodies. They are interpreted to be tectonic in nature, the result of a thrust fault developed in rocks that are otherwise structurally sound. Faults (planar fractures) come in several styles: Normal faults occur when one slab of rock (the hanging wall) slides below the level of a neighboring slab of rock (the foot wall).

Thrust faults (also called reverse faults when the fault angle is greater than 45 degrees to the horizontal) are the opposite of a normal fault. Instead of the hanging wall slipping below the foot wall, the hanging wall is thrust above the foot wall. In general, normal faults are the result of regional or local extension, while thrust and reverse faults give evidence of compression.

Full 2-km wide field of view of LROC NAC frame M118031613L allows a longer north-south look at the scarp, kin to the Lincoln Scarp visited by Cernan and Schmidt at Taurus Littrow (Apollo 17). At his point the scarp runs parallel with the inner slope of an unnamed crater within Xenophanes [NASA/GSFC/Arizona State University].

Context LROC Wide Angle Camera (WAC) monochrome (643 nm) observation M145154636C showing the lobate scarp running in a semi-circle along the wall of a degraded crater within Xenophanes; field of view 44 km, LRO orbit 6325, November 23, 2010 [NASA/GSFC/Arizona State University].

So what mechanism produces lobate scarps? On Mercury, lobate scarps are large and globally distributed, and have been interpreted to be the result of global contraction of the planet. What could make an entire planet contract? How about the slow cooling of its interior.

Data from LROC indicates that the lobate scarps on the Moon are also distributed globally. However, they are also small and deform the regolith locally. Because these faults are located in relatively unconsolidated material, they must be very young because the regolith is constantly churned by small asteroid and comet impacts. Scientists have thus interpreted the lunar scarps to be the result of late-stage, not early-stage, global contraction of the Moon!

LOLA altimetry of a 360 square kilometer area around the crater hosting the lobate scarp, within Xenophanes clearly shows striation channels radiant to Mare Imbrium, whose center basin beyond Oceanus Procellarum, seen at the eastern edge of the field, is 1700 km away. Procellarum's elevation, as deep as it is (here ~3100 meters below lunar mean, is more than three km higher than the flooded floor of Xenophanes. Perhaps the latter, more ancient impact floor was flooded from below. Some features nearby are radiant to the more distant Orientale impact basin [NASA/GSFC/MSFC/LMMP].

Can you trace the entire length of the lobate scarp in the full NAC frame?

Related Posts:
Wrinkled Planet
Right Angle
Aitken Crater Constellation ROI