This high-resolution image shows the intersection of two crater rims. The full craters can be seen in this context image -- the high-resolution image covers the rim intersection very close to the context image center. Downslope movement of material in the crater wall has exposed fresh, brighter soil.
This image was acquired as a high-resolution targeted observation. Targeted observations are images of a small area on Mercury's surface at resolutions much higher than the 200-meter/pixel morphology base map. It is not possible to cover all of Mercury's surface at this high resolution, but typically several areas of high scientific interest are imaged in this mode each week.
Date acquired: March 10, 2014 Image Mission Elapsed Time (MET): 36770148 Image ID: 5908044 Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS) Center Latitude: 65.02° Center Longitude: 255.4° E Resolution: 12 meters/pixel Scale: This image is approximately 8.8 km (5.5 mi.) across. Incidence Angle: 73.1° Emission Angle: 5.8° Phase Angle: 78.9°
These two relatively fresh craters, ~34 km (21 miles) and ~20 km (12 miles) across, share a rim and both contain slumped material. Did they form during the same event, by two impactors? Did the rim of the large, highly degraded crater on the right side of the image influence the structure of the shared rim? Higher-resolution images taken during MESSENGER's final year of operations may help to elucidate their origin.
This image was acquired as part of MDIS's high-resolution stereo imaging campaign. Images from the stereo imaging campaign are used in combination with the surface morphology base map or the albedo base map to create high-resolution stereo views of Mercury's surface, with an average resolution of 200 meters/pixel. Viewing the surface under the same Sun illumination conditions but from two or more viewing angles enables information about the small-scale topography of Mercury's surface to be obtained.
Date acquired: October 12, 2011 Image Mission Elapsed Time (MET): 226922649 Image ID: 876240 Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS) WAC filter: 7 (748 nanometers) Center Latitude: 64.76° Center Longitude: 255.5° E Resolution: 269 meters/pixel Scale: The large crater at the image center is approximately 34 km (21 mi.) across. Incidence Angle: 72.9° Emission Angle: 14.3° Phase Angle: 60.6°
This stunning image shows a portion of the sharp rim of an unnamed, ~28 km (17 mile) diameter complex crater. The upper right portion of the image lies outside of the crater, and the lower left portion of the image lies on the crater floor. The crater at the center of the image lies on the crater wall. North is to the right.
This image was acquired as a high-resolution targeted observation. Targeted observations are images of a small area on Mercury's surface at resolutions much higher than the 200-meter/pixel morphology base map. It is not possible to cover all of Mercury's surface at this high resolution, but typically several areas of high scientific interest are imaged in this mode each week.
Date acquired: March 14, 2014 Image Mission Elapsed Time (MET): 37087259 Image ID: 5930668 Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS) Center Latitude: 78.14° Center Longitude: 278.3° E Resolution: 16 meters/pixel Scale: This image is approximately 10.5 km (6.5 mi.) across. Incidence Angle: 78.4° Emission Angle: 39.7° Phase Angle: 118.1°
The Sun's light provides a powerful tool for understanding the composition of materials in the Solar System. Today's image features two views of Mercury provided by the Mercury Atmospheric and Surface Composition Spectrometer (MASCS) instrument. As the Sun's light hits the surface of Mercury, the Visible and Infrared Spectrograph (VIRS) portion of MASCS measures many wavelengths of the reflected light from a single spot on the surface at a time. These observations create a spectral profile of the surface as MESSENGER orbits Mercury. In each panel, the top left corner of the image is 70°N,180°E and the bottom right corner is 70°S,180°E. Most of Caloris basin can be seen along the right edge of each panel. The top panel is a monochromatic image of the interpolated 750 nm reflectance, and the bottom panel shows the same data but in a false color composite selected to highlight compositional variations on the surface.
Instruments: Visible and Infrared Spectrograph (VIRS) of the Mercury Atmosphere and Surface Composition Spectrometer (MASCS) Center Latitude: 0° Center Longitude: 0° E Map Projection: Simple Cylindrical VIRS Monochromatic Wavelength: 750 nm VIRS Color Composite Wavelengths: 575 nm as red, 415 nm/750 nm as green, 310 nm/390 nm as blue Scale: Caloris Basin is 1,550 km (963 mi) across.
Scientists have known since Mariner 10 that Mercury has contracted. This contraction is a result of the cooling of Mercury's interior, and is the process responsible for the formation of the planet's wrinkle ridges and lobate scarps. For almost four decades, however, the amount of global contraction measured from spacecraft data has been substantially less than that predicted by models of the thermal evolution of Mercury.
Now, using global photogeological and topographic MESSENGER data of Mercury, members of the MESSENGER team have mapped almost 6,000 ridges and scarps across the planet. Today's image shows the result of this mapping work, with structures color-coded according to one of four classes. (The global photogeological and topographic data used in this study are shown in the bottom left and right, respectively, of the image.) With these results, the MESSENGER team has calculated that Mercury contracted to a much greater extent than had been determined previously from mapping -- by up to seven times more, in fact.
This study was published online in the journal Nature Geoscience on Sunday, March 16, 2014, and is being presented today in the "Mercury" session at the 45th Lunar and Planetary Science Conference, which is being held this week in The Woodlands, Texas. In total, MESSENGER team members are presenting 25 papers at this conference.
Date published online: March 16, 2014 Center Latitude: 0° Center Longitude: 0°E Projection: Molleweide Reference: Byrne et al. (2014) Mercury's global contraction much greater than earlier estimates, Nature Geoscience, doi:10.1038/NGEO2097
New images obtained during low-altitude opportunities when the MESSENGER spacecraft is closest to the surface have revealed a small lobate scarp, identified here with white arrows. Cooling of Mercury's interior over billions of years has caused the planet to contract, forming a network of large landforms called lobate scarps, many over a kilometer high and hundreds of kilometers long. One of the goals for MESSENGER's current extended mission is to determine if there is evidence of young fault scarps that indicate recent contraction of Mercury due to interior cooling and continued solidification of the core. This scarp is only 2 km long, the shortest fault scarp yet found on Mercury. Landforms of this scale must be young, because small features will not survive for billions of years under constant meteoroid bombardment. Lobate scarps of the same scale found on the Moon are thought to be no more than 800 million years old and could be less than 50 million years old. Thus, this small scarp and others likely to be discovered in low-altitude images could provide evidence of very recent contraction of Mercury.
This image was acquired as a high-resolution targeted observation. Targeted observations are images of a small area on Mercury's surface at resolutions much better than that of the 200-meter/pixel morphology base map. It is not possible to cover all of Mercury's surface at this high resolution, but typically several areas of high scientific interest are imaged in this mode each week.
Date acquired: February 09, 2014 Image Mission Elapsed Time (MET): 34263837, 34263839 Image ID: 5729947, 5729948 Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS) Center Latitude: 65.8° Center Longitude: 64.8° E Resolution: 17 meters/pixel Scale: 2-kilometer (1.2-mile) scale bar shown on the image Incidence Angle: 79.7° Emission Angle: 33.5° Phase Angle: 113.3°
This image was acquired as part of the NAC ride-along imaging campaign. When data volume is available and MDIS is not acquiring images for its other campaigns, high-resolution NAC images are obtained of the surface. These images are designed not to interfere with other instrument observations but take full advantage of periods during the mission when extra data volume is available.
Date acquired: February 16, 2014 Image Mission Elapsed Time (MET): 34838972 Image ID: 5770878 Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS) Center Latitude: -14.11° Center Longitude: 26.85° E Resolution: 41 meters/pixel Scale: Berkel crater is 22 kilometers (14 miles) in diameter Incidence Angle: 33.2° Emission Angle: 48.4° Phase Angle: 30.1° Orientation: North is toward the bottom of this image.
This image was acquired as part of the MDIS low-altitude imaging campaign. During MESSENGER's second extended mission, the spacecraft makes a progressively closer approach to Mercury's surface than at any previous point in the mission, enabling the acquisition of high-spatial-resolution data. For spacecraft altitudes below 350 kilometers, NAC images are acquired with pixel scales ranging from 20 meters to as little as 2 meters.
Date acquired: March 07, 2014 Image Mission Elapsed Time (MET): 36539529 Image ID: 5891638 Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS) Center Latitude: 51.90° Center Longitude: 267.53° E Resolution: 7.9 meters/pixel Scale: This image is about 8 kilometers (5 miles) across Incidence Angle: 63.2° Emission Angle: 14.9° Phase Angle: 78.0°
The images for MDIS's high-resolution 3-color mosaic were acquired during MESSENGER's second year in orbit about Mercury. The 3-color mosaic was designed to complement the 8-color base map acquired during MESSENGER's primary mission. By imaging Mercury's surface in a subset of the color filters at the highest resolution possible, the 3-color mosaic is available at 332 meters/pixel,as compared to 665 meters/pixel for the 8-color mosaic.
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS) WAC filters: 9, 7, 6 (996, 748, 433 nanometers) in red, green, and blue Center Latitude: -14.9° Center Longitude: 10.3° E Resolution: 332 meters/pixel Scale: Derain has a diameter of 167 km (104 miles) Projection: simple cylindrical
On March 5 we saw an area to the west of Caloris. Today we travel to the east of the basin, another area that is thought to be related to ejecta from the Caloris basin impact event. The knobs and unusual corrugated texture are part of Odin Planitia and may have formed from ejecta and impact melt. Schiaparelli Dorsum, nearly aligned with the terminator (the division between the dayside and night side of the planet), cuts across the scene from top to bottom.
This image was acquired as part of MDIS's high-incidence-angle base map. The high-incidence-angle base map complements the surface morphology base map of MESSENGER's primary mission that was acquired under generally more moderate incidence angles. High incidence angles, achieved when the Sun is near the horizon, result in long shadows that accentuate the small-scale topography of geologic features. The high-incidence-angle base map was acquired with an average resolution of 200 meters/pixel.
Date acquired: July 07, 2012 Image Mission Elapsed Time (MET): 250134169 Image ID: 2154159 Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS) WAC filter: 7 (748 nanometers) Center Latitude: 24.83° Center Longitude: 195.2° E Resolution: 228 meters/pixel Scale: This scene is approximately 400 km (250 miles) across Incidence Angle: 88.8° Emission Angle: 53.2° Phase Angle: 142.0°
Small knobs and crater rims just barely catch the sunlight with the Sun low on Mercury's eastern horizon. The relatively smooth floor of the Caloris basin is on the right, and the rim and exterior of the basin are to the left. The knobby texture outside of the basin may be the result of blocks of material that were ejected by the basin-forming impact.
This image was acquired as part of MDIS's high-incidence-angle base map. The high-incidence-angle base map complements the surface morphology base map of MESSENGER's primary mission that was acquired under generally more moderate incidence angles. High incidence angles, achieved when the Sun is near the horizon, result in long shadows that accentuate the small-scale topography of geologic features. The high-incidence-angle base map was acquired with an average resolution of 200 meters/pixel.
Date acquired: April 27, 2012 Image Mission Elapsed Time (MET): 244054579 Image ID: 1721895 Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS) WAC filter: 7 (748 nanometers) Center Latitude: 40.19° Center Longitude: 140.5° E Resolution: 270 meters/pixel Scale: This scene is approximately 492 km (306 miles) across Incidence Angle: 88.2° Emission Angle: 53.7° Phase Angle: 142.0°
The beautiful Abedin crater is featured in today's image. The crater's sunlit wall meets the crater floor, which occupies the left side of the scene. The floor is largely covered with rock that was melted by the Abdedin impact, ponded on the crater floor, and has now solidified, cracking as it cooled.
This image was acquired as a high-resolution targeted observation. Targeted observations are images of a small area on Mercury's surface at resolutions much higher than the 200-meter/pixel morphology base map. It is not possible to cover all of Mercury's surface at this high
Date acquired: September 23, 2013 Image Mission Elapsed Time (MET): 22252071 Image ID: 4875876 Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS) Center Latitude: 62.28° Center Longitude: 352.0° E Resolution: 16 meters/pixel Scale: Abedin crater is 116 km (72 miles) in diameter Incidence Angle: 83.6° Emission Angle: 22.1° Phase Angle: 105.8°
A series of troughs extends diagonally (southwest-northeast) across this high-resolution image of the interior of the Caloris basin. The troughs are graben: structures that developed where horizontal forces pulled the crust apart, causing valleys to form as sections of rock dropped down between two inward-dipping faults. Pulling-apart ("extensional") deformation is much less common on Mercury than is compressional deformation. However, a large number of graben are found within Caloris. This network of graben, named Pantheon Fossae, is the subject of a blog essay recently posted on the website of The Planetary Society.
This image was acquired as a high-resolution targeted observation. Targeted observations are images of a small area on Mercury's surface at resolutions much higher than the 200-meter/pixel morphology base map. It is not possible to cover all of Mercury's surface at this high resolution, but typically several areas of high scientific interest are imaged in this mode each week.
Date acquired: January 19, 2012 Image Mission Elapsed Time (MET): 235472082 Image ID: 1285755 Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS) Center Latitude: 27.3° Center Longitude: 160.7° E Resolution: 24 meters/pixel Scale: The scene is about 43 km (27 mi.) across Incidence Angle: 76.8° Emission Angle: 54.9° Phase Angle: 131.8°
North is up in this image.
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