Catullus Crater Anaglyph

With your red-cyan glasses on, check out this stereo view inside the complex crater Catullus. Here you can see the central peaks rising above the relatively smooth floor of the crater. To the right of the peaks, a large, irregularly shaped pit sinks down below the level of the crater floor. This pit may have formed due to past volcanic activity within the impact crater.

These images were acquired as a targeted set of stereo images. Targeted stereo observations are acquired at resolutions much higher than that of the 200-meter/pixel stereo base map. These targets acquired with the NAC enable the detailed topography of Mercury's surface to be determined for a local area of interest.

Date acquired: July 25, 2014
Image Mission Elapsed Time (MET): 48654092, 48654444
Image ID: 6751776, 6751777
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 21.91°
Center Longitude: 292.8° E
Resolution: 48 meters/pixel
Scale: Pit is approximately 18 km (11 miles) across
Incidence Angle: 68.5°
Emission Angle: 11.9°
Phase Angle: 73.0°

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

To Ngoc Van Crater

Crater To Ngoc Van, named for a Vietnamese painter, is seen at the top of this image. The oblique angle provides a great view into the irregularly shaped pit within To Ngoc Van, which is thought to have formed via explosive volcanism and provides evidence for Mercury's geologically active past. Many of the smaller (5-10 km) craters in this scene were produced as secondary impacts from the ejecta of nearby Ahmad Baba crater. North is to the left in this image.

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: November 19, 2013
Image Mission Elapsed Time (MET): 27148228
Image ID: 5223996
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: 53.36°
Center Longitude: 239.6° E
Resolution: 154 meters/pixel
Scale: Crater To Ngoc Van is 71 km (44 miles) in diameter
Incidence Angle: 73.7°
Emission Angle: 65.6°
Phase Angle: 30.0°

Photo credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Impact Crater with Pit Crater

The impact crater at the top center of this image is characterized by a sharp rim and high-reflectance ejecta. Lobes of slumped material are found where the wall meets the floor. The central peak is notable because it contains a pit. A recent survey1 found 27 central pit craters on Mercury. All of these central pit craters are located in plains units, but the mechanism by which the pits form is uncertain.

1 Z. Xiao and G. Komatsu (2013), Impact craters with ejecta flows and central pits on Mercury, Planetary and Space Science, vol. 82-83, pp. 62-78.

This image was acquired as part of MDIS's high-resolution surface morphology base map. The surface morphology base map covers more than 99% of Mercury's surface with an average resolution of 200 meters/pixel. Images acquired for the surface morphology base map typically are obtained at off-vertical Sun angles (i.e., high incidence angles) and have visible shadows so as to reveal clearly the topographic form of geologic features.

Date acquired: July 17, 2011
Image Mission Elapsed Time (MET): 219350124
Image ID: 513704
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 19.42°
Center Longitude: 63.27° E
Resolution: 143 meters/pixel
Scale: The impact crater of interest is about 17 km (11 mi.) in diameter
Incidence Angle: 59.8°
Emission Angle: 12.8°
Phase Angle: 47.0°

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Crescent Mercury

Although its geologic history was very different from that of our closest celestial neighbor, it's fun to see Mercury in the familiar crescent we associate with the Moon. Though the extreme viewing angle makes it hard to tell, this irregular pit is near the center of the sunlit sliver.

This image was acquired as part of MDIS's limb imaging campaign. Once per week, MDIS captures images of Mercury's limb, with an emphasis on imaging the southern hemisphere limb. These limb images provide information about Mercury's shape and complement measurements of topography made by the Mercury Laser Altimeter (MLA) of Mercury's northern hemisphere.

Date acquired: October 09, 2013
Image Mission Elapsed Time (MET): 23631997
Image ID: 4974136
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: -53.19°
Center Longitude: 121.8° E
Resolution: 655 meters/pixel
Incidence Angle: 96.8°
Emission Angle: 67.9°
Phase Angle: 140.3°

Photo credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Lava Channels Near Kofi Crater

This image is a portion of the MDIS global mosaic basemap that was acquired during MESSENGER's first year in orbit. Of particular note is the flat-floored, southeast-trending valley in the center of the image, which starts near several depressions to the top left of the image, and connects with the Kofi crater (center right).

This valley is interpreted by MESSENGER team scientists as a broad lava channel, formed by the mechanical and thermal erosion of Mercury's surface by hot, low-viscosity, quickly-flowing lavas. The pits to the top left may be source vents for the lava flows that formed the channel; these flows then filled the Kofi crater at the channel's other end. Another lava channel, with a similar southeast trend, lies at the top right of the image, and there is a total of five broad channels in this region.

Determining how these channels formed, how rapidly they shaped the landscape, and how they relate to other volcanic features on Mercury -- such as expansive smooth plains nearby -- is important in understanding the role of volcanism on Mercury. Moreover, similar broad channels do not appear to exist elsewhere on Mercury, making this region a particularly interesting locale.

Date Created: February 10, 2012
Instrument: Mercury Dual Imaging System (MDIS)
Latitude Range: 54.3° N to 61.3° N
Longitude Range: 109.4° E to 121.6° E
Resolution: 146 meters/pixel
Scale: Kofi, the large impact crater at center right, is approximately 135 km (84 mi.) in diameter
Projection: Azimuthal equidistant

Photo credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Pit in Tolstoj Basin

The Tolstoj basin is located in Mercury's southern hemisphere, and is 355 km (220 miles) in diameter. This oblique image shows an elongate pit inside Tolstoj, a basin whose floor appears to have been flooded by lavas. The pit lacks the raised rim of an impact crater, and may have formed when magma withdrew from a shallow chamber, causing an unsupported area of the surface to collapse. The low-angle lighting in this image hides the floor of the pit, making it appear much deeper than it actually is. The pit is aligned approximately north-south.

Date acquired: January 11, 2012
Image Mission Elapsed Time (MET): 234752446
Image ID: 1251011
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -16.97°
Center Longitude: 198.1° E
Resolution: 99 meters/pixel
Scale: This image shows a field of view approximately 150 km (93 miles) across
Incidence Angle: 84.8°
Emission Angle: 58.6°
Phase Angle: 135.6°

Photo credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Note: These types of pit craters are fairly commonplace on Mars; for example, see Crater and Skylight on Pavonis Mons and Dark Rimless Pits in the Tharsis Region. That similar features should be present on Mercury is, to me, not surprising at all.

Hollows in Scarlatti's Basin

Scarlatti is a peak-ring basin with a diameter of 132 kilometers. Just north of the inner peak ring on the basin's floor is a large oblong pit, shown here in the highest resolution ever obtained. The large pit may have formed as a volcanic collapse feature, and this high-resolution view shows many hollows located on the pit's wall. Members of the MESSENGER team are using images like this one to unravel the geologic relationship between Scarlatti's pit and these newly seen hollows.

Date acquired: December 08, 2011
Image Mission Elapsed Time (MET): 231863738
Image ID: 1111610
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 41.53°
Center Longitude: 259.1° E
Resolution: 29 meters/pixel
Scale: This image is approximately 30 kilometers (19 miles) across
Incidence Angle: 81.2°
Emission Angle: 10.7°
Phase Angle: 92.0°

Photo credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington