Komarov

A small, fresh crater can be seen on the right side of this image on the floor of Komarov crater. The crater was formed when an impactor smashed into the wall of one of the fractures (or graben) in the crater floor. Some of the ejecta from the impact can be seen draping the wall of the graben. This graben is one of many in the floor of Komarov. Image credit: NASA/GSFC/ASU [full feature]

Starry Night

This image shows the slopes found near the south pole of the Moon, poleward of 75 degrees South. The bright red to white areas have the highest slopes (25 degrees or more) while the dark blue to purple areas have the smallest slopes (5 degrees or less). The largest slopes are found in impact crater rims, which appear as brightly colored circular features throughout the image. Image credit: NASA/GSFC/MIT [full feature]

Copernicus in Color!

Copernicus crater, a 96 km wide crater on the near side of the Moon, is featured in false color in this image from the LRO Wide Angle Camera (WAC). Filters in visible and ultraviolet wavelengths were combined to bring out the subtle differences in reflected light in this image. Scientists use images like this to study differences in composition of the surface materials. Image Credit: NASA/GSFC/ASU [hi-resolution]

Impact art

This image shows a small portion of the ejecta blanket of an unnamed fresh impact crater (1 km diameter) located on the southeastern wall of crater Darwin C (15 km diameter, over 2500 m deep!). The linear reflectance boundary that runs diagonally from lower left to upper right is a break in slope between the steep wall (lower right) and floor (upper left) of Darwin C crater; to the left of that line the floor is essentially flat. Exposure to space weathering tends to lower the brightness of surface materials on an airless body like the Moon. But compositional differences also affect the reflectance of surface materials. Image Credit: NASA/GSFC/ASU [full feature]

Layering Waves

This image is a broader mosaic of the source where the ejecta in the "Impact Art" image originated. This unnamed crater does not have a circular shape, because it formed on the sloped wall of Darwin C crater. Soon after impact, gravity took over, pulling large boulders and fine debris down the crater wall. Image credit: NASA/GSFC/ASU [full feature]

Clerke Crater

The interior wall of the Clerke crater has many distinct flows of granular material which narrow as they reach towards the floor of the crater. The source material originates from the crater rim. The debris appear higher in reflectance compared to the rest of the crater wall, likely due to differences in the length of time they have been exposed to the space environment and perhaps grain size of the material. The debris flows may be younger than the crater floor and walls if the flow was instigated by seismic shaking or a nearby impact crater. The flow may contain more boulders, which may cause the higher reflectance. The crater is 7 km in diameter located at 21.7°N, 29.8°E near the Taurus Littrow Valley where Apollo 17 landed on 11 December 1972 and is named after Agnes Mary Clerke, an English astronomer. Image credit: NASA/GSFC/ASU [full feature]

Layering in Messier A

Like sand sifted through the fingers of a giant, loose debris beautifully ornaments the slopes of the Messier A crater walls. Outcropping bedrock projections stand in relief against avalanches that once flowed on either side. This is yet another region of mare deposit where we see evidence for multiple, thin lava flows, now exposed in cross-section by the excavations of an impact. This fine layering is a surprise to planetary scientists - one of the many revelations about the Moon made with high resolution imaging. [full feature]

Beautiful Ejecta Patterns

This image highlights an unnamed small crater (roughly 180 m in diameter) located at the northern edge of Mare Fecunditatis, near the crater chain known as Catena Taruntis. The strong reflectance contrast between the ejecta deposit and the surrounding background in the opening image suggests that this crater is still very flesh and young. The low reflectance materials in the center of this crater are probably impact melts or a different rock type in the subsurface that was excavated by the impact. The numerous dark dots intermixed with the high reflectance ejecta might be same dark materials as the one on the crater floor, or more likely secondary craters excavating the background mature material. This beautiful ejecta field consists of numerous lobes systematically piled on the top of adjacent outer lobes, resulting in a view like a stop motion picture of the impact event. Apparently, ejecta that landed far away from the impact center settled on the ground earlier than the portion that traveled a shorter distance. High resolution images of these very fresh craters supply key information about impact cratering, which improves our knowledge of the craters and helps to reveal the history of any airless planetary bodies in our solar system. Image credit: NASA/GSFC/ASU [full feature]

Dichotomy

The wall of this 8.5 km diameter, Copernican-aged crater (located at 3.29°N, 100.25°W) is streaked with dark material. When geologists describe different surfaces on the Moon or other planetary objects, we use the terms "high reflectance" and "low reflectance." In this case, the wall of the crater is high reflectance, but some of the material that has flowed down the wall is low reflectance. What is the cause of the low reflectance of this material? How is it different from the high reflectance crater wall? Are the differences caused by composition, grain size, or both? Also, is this flow a granular flow, or an impact melt flow? Sometimes these two types of flow can behave similarly. Some quick observations can point us in the right direction. First, the crater is located on the far side of the Moon, in an area of highlands. This location most likely means that we are not observing a compositional difference, as there are no nearby sources of mare basalt that could account for the low-reflectance material. Second, in this particular NAC frame there is no evidence for impact melt deposits around the rim of the crater, although you can find evidence of impact melt in the crater floor. The crater is not large enough to develop terraces where impact melt can pool and then flow out. So this flow is probably granular, not molten. Image credit: NASA/GSFC/ASU [full feature]

Tycho Central Peak Spectacular

* CONTEST WINNER!

On 10 June 2011 the LRO spacecraft slewed 65° to the west, allowing the LROC NACs to capture this dramatic sunrise view of Tycho crater. A very popular target with amateur astronomers, Tycho is located at 43.37°S, 348.68°E, and is ~82 km (51 miles) in diameter. Tycho's features are so steep and sharp because the crater is young by lunar standards, only about 110 million years old. Over time, micrometeorites, and not so micro meteorites, will grind and erode these steep slopes into smooth mountains. Image credit: NASA/GSFC/ASU [full feature]

Linne Topography

Linné (2.2 km diameter) is a very young and beautifully preserved impact crater. LROC stereo images provide scientists with the third dimension - information critical for unraveling the physics involved in impact events. LROC NAC Digital Terrain Models (DTM) are made from geometric stereo pairs (two images of the same area on the ground, taken from different view angles under nearly the same illumination). LROC was not designed as a stereo system, but can obtain stereo pairs through images acquired from two orbits (with at least one off-nadir slew). Image credit: NASA/GSFC/ASU. [full feature]

Debris in Dionysius

Dionysius crater (17.297°E, 2.766°N)is situated on the western edge of Mare Tranquillitatis (the Sea of Tranquility) and excavates both highlands (bright, high reflectance) and mare (dark, low reflectance) materials. Dark banded layers of mare peek out of the eastern wall, where mare material was disturbed by the impact that formed Dionysius crater. Bright talus trails wind downslope through crags and crannies in the dark mare scarps. Looking closely, the mare appears banded or striated, indicating a non-uniform material. In general, mare are thought to form from large volumes of fluid lavas, much like the Columbia River Basalts in the Pacific Northwest of North America. The stratifications in the lunar mare may represent a series of lava flows in the region. Image credit: NASA/GSFC/ASU [full feature]

Diviner North Pole Minimum Temperature

This image features night time temperatures at the Moon's north pole as measured by the Diviner instrument. Areas in blue and purple represent colder temperatures, while areas in orange and red represent warmer temperatures. At any given point in the Moon's orbit, half of the Moon is in daylight, while half of the Moon is in darkness. At the poles, we might expect that half of the image would be much hotter than the other. Image credit: NASA/GSFC/UCLA

Mini RF Rozhdestvenskiy

This image is a mosaic of data collected from the Mini-RF instrument at the lunar north pole. The inset shows an un-named crater within Rozhdestvenskiy crater that potentially holds water ice. Scientists analyze the radar backscatter to understand what lies beneath the surface of the Moon. In the case of some craters near the Moon's poles, high backscatter indicates the potential for water ice. Image credit: NASA/GSFC/JHUAPL [full feature]

Contrast Crater Wall

After the unimaginably violent processes of excavation and ejecta emplacement, impact craters gradually change their shapes with time by various processes. This image highlights post-impact degradation processes.The lower half of this image (relatively high reflectance) is the crater wall, downslope is to the bottom. The bottom-left dark area is the shadow of southern crater rim. Upper half of the image with a low reflectance surface is the crater rim and the rim slope out of the cavity, mostly covered with impact melt. The low reflectance area at the image center just above the steep wall has multiple horizontal cracks showing where the hardened impact melt has cracked as the steep walls slowly fail and slide into the crater bit-by-bit. These slope failures continuously refresh the crater walls, removing the melt coatings and exposing subsurface materials. Image credit: NASA/GSFC/ASU [full feature]

Mare Ingenii

This image is a spectacular oblique viewpoint, similar to what an astronaut in orbit would observe looking 58° from vertical. The swirls of bright material in the oblique image stand out from the dark mare surface, resulting from an albedo (brightness) contrast. Scientists are particularly interested in the cause of this albedo contrast; does it result from different minerals in the surface materials? One possibility is that the bright areas are less weathered than the darker areas, possibly due to a local magnetic field that shields the surface from the solar wind in the space environment. Image credit: NASA/GSFC/ASU [full feature]

Apollo 17 Oblique

In the lower right, South Massif casts a long evening shadow across the mare basalt flooded Taurus Littrow valley. Note the sharp boundary of the flat mare against the slopes of the Sculptured Hills in the background, similar to a lake shoreline, revealing the very fluid nature of the lava when it filled the valley. Your eye is drawn to the sharp line snaking across the bottom of the image. Note how this ridge traverses across the valley floor and up onto the lower slopes of North Massif (lower left). Astonishingly this feature is a large, young fault: imagine the ground in the foreground being pushed to the east and the crust buckling, a whole section was pushed up and onto the back side of the fault (low angle thrust fault). Image credit: NASA/GSFC/ASU

Tsiolkovsky Central Peak

This image is a spectacular LROC NAC oblique view looking East at the central peak of Tsiolkovskiy crater. This large impact crater, with a diameter of 185 km, is located on the farside at 20.38°S latitude and 128.97°E longitude. It is classified as a complex crater because of its terraced walls, scalloped rim, and central peak, which rises over 3400 m from the crater floor. Central peaks of craters form in a matter of seconds from very energetic impact events. The tremendous pressure imparted from the impactor on to the target rock causes it to behave like a plastic for a few brief seconds. An imperfect analogy is a water droplet splashing into water, at first which produces a central jet, the fluid-like behavior of rock after the impact causes it to rebound upwards. Another factor assisting in the uplift of a central peak is the gravitational collapse of the crater walls which pushes material in the center upwards. Image credit: NASA/GSFC/ASU [full feature]

Lamp Lyman Alpha Map

This image, produced by LAMP aboard NASA's LRO reveal features at the Moon's south poles in the regions that lie in perpetual darkness. They show many permanently shadowed regions, or PSRs, are darker at far-ultraviolet wavelengths and redder than nearby surface areas that receive sunlight. The darker PSR regions are consistent with having large surface porosities (indicating "fluffy" soils) while the reddening is consistent with the presence of water frost on the surface. Image credit: NASA/GSFC/SwRI. [full feature]

Faces of Shackleton

This image shows four "faces" of Shackleton Crater, a 21 km diameter crater located at the south pole of the Moon. Because of its location, most of Shackleton's interior lies in permanent shadow. In the upper left, topography from the LOLA laser altimeter reveal the shape of the crater interior. The upper right image shows the visible lighting conditions in an image from the SMART-1 mission. The lower right image is a lighting map (brighter is longer periods of illumination) from the LRO Camera. The lower left image is a radar image from the Mini-RF instrument draped over a shaded relief map. Image credit: NASA/GSFC/ASU/JHUAPL/MIT/SwRI [hi-resolution]

South Pole-Aitken Basin

This LOLA topographic map centers on the South Pole-Aitken (SPA) basin, the largest impact basin on the Moon (diameter = 2600 km), and one of the largest impact basins in the Solar System. The distance from its depths to the tops of the highest surrounding peaks is over 15 km, almost twice the height of Mount Everest on Earth. SPA is interesting for a number of reasons. To begin with, large impact events can remove surficial materials from local areas and bring material from beneath the impact craters to, or closer to, the surface. The larger the crater, the deeper the material that can be exposed. As SPA is the deepest impact basin on the Moon, more than 8 km deep, the deepest lunar crustal materials should be exposed here. In fact, the Moon's lower crust may be revealed in areas within SPA: something not found anywhere else on the Moon. Image credit: NASA/GSFC/MIT

LEND Water South Pole

This image, created from data from the Lunar Exploration Neutron Detector (LEND) instrument, shows locations where fewer neutrons have been detected at the lunar south pole. The presence of hydrogen in the lunar soil reduces the number of neutrons that flow out from the Moon. To map out likely deposits of water ice, LEND scientists look for places that have fewer neutrons. Locations that appear blue suggest higher concentrations of hydrogen, and possible water ice. [full feature]

Giordano Bruno Whorl

The crater Giordano Bruno is a favorite of lunar scientists due to its relatively young age and the amazing impact melt features found within and without the crater walls.This image uses a 57 cm per pixel Narrow Angle Camera frame to highlight the details of a giant swirl (or whorl) of impact melt within one of the larger impact melt pools inside Giordano Bruno. The whorl formed in a clockwise direction and is ~1 km in diameter. This spiral-shaped feature may have formed due to shear stress created when molten impact melt flowed at different speeds (probably caused by drag from the pool floor or an obstacle within the pool). This shear would modify flow directions in ways that could ultimately produce such a swirling pattern. Slumping material may have set the melt into motion within an otherwise calm impact melt pool. The more information lunar scientists can gather about how quickly impact melt cools, the more we will know about how this structure formed! Image credit: NASA/GSFC/ASU [full feature]