Butterfly Vent

This color view of Mercury's surface highlights what may be an old volcanic vent. Just to the right of center, within a brown-red patch, is an irregularly shaped 30-km depression, in this case the irregular shape is a bit like a butterfly. While most of these suspected volcanic vents are located within impact craters (like this one), the butterfly-shaped vent is not clearly associated with any crater. It also appears that it may be older than other vents, resulting in more subdued details and colors.

This image was acquired as part of MDIS's high-resolution 3-color imaging campaign. The map produced from this campaign complements the 8-color base map (at an average resolution of 1 km/pixel) acquired during MESSENGER's primary mission by imaging Mercury's surface in a subset of the color filters at the highest resolution possible. The three narrow-band color filters are centered at wavelengths of 430 nm, 750 nm, and 1000 nm, and image resolutions generally range from 100 to 400 meters/pixel in the northern hemisphere.

Date acquired: July 11, 2014
Image Mission Elapsed Time (MET): 47381178, 47381170, 47381174
Image ID: 6661702, 6661700, 6661701
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: 32.08°
Center Longitude: 21.71° E
Resolution: 243 meters/pixel
Scale: This scene is approximately 250 km (155 miles) across
Incidence Angle: 32.7°
Emission Angle: 0.5°
Phase Angle: 33.2°

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

Hemingway Crater

Hemingway crater is seen in this color view of Mercury's surface. Hemingway is the 130-km (81-mile) diameter crater with a relatively brown floor and small patch of dark blue in its center. This impact crater has irregular depressions on its floor, which are fairly common in other impact craters and may be due to explosive volcanic events, but the low-reflectance, blue patch on the floor may point to a more complex history.

This image was acquired as a high-resolution targeted color observation. Targeted color observations are images of a small area on Mercury's surface at resolutions higher than the 1-kilometer/pixel 8-color base map. During MESSENGER's one-year primary mission, hundreds of targeted color observations were obtained. During MESSENGER's extended mission, high-resolution targeted color observations are more rare, as the 3-color base map covered Mercury's northern hemisphere with the highest-resolution color images that are possible.

Date acquired: July 15, 2014
Image Mission Elapsed Time (MET): 47756996, 47757016, 47757000
Image ID: 6688394, 6688399, 6688395
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: 16.51°
Center Longitude: 356.9° E
Resolution: 288 meters/pixel
Scale: This scene is about 290 km (180 miles) across
Incidence Angle: 19.2°
Emission Angle: 60.3°
Phase Angle: 77.9°

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

Smooth Terrain Near a Volcanic Vent

The smooth, rolling terrain in this high resolution image looks almost like sand dunes or ripples on a beach. The smooth texture of this region is due to a blanket of pyroclastic material from the volcanic vent located about 85 km to the south of it. To put the size of this image into perspective, a human could run the length of this image in less than an hour (if they could breathe on Mercury, that is!).

Date acquired: August 04, 2014
Image Mission Elapsed Time (MET): 49462358
Image ID: 6809127
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 38.03°
Center Longitude: 63.23° E
Resolution: 6 meters/pixel
Scale: This image is 6.1 km (3.8 mi.) wide.
Incidence Angle: 68.7°
Emission Angle: 29.5°
Phase Angle: 78.3°

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

Seuss Crater

In the top left part of this image is Seuss, a complex crater with hollows present on the crater's floor. In this enhanced color image, the hollows appear as bright blue-white features. Just outside of Seuss' rim, you can see some material that appears darker brown in the image. This is LRM, or Low Reflectance Material, and was probably excavated by the impactor when Seuss was formed. Extending from Seuss are bright crater rays, which are streams of ejecta that were thrown from the crater upon impact. In the bottom right of the image, you can see an irregularly shaped, orange-yellow depression that could be a volcanic vent.

This image was acquired as part of MDIS's high-resolution 3-color imaging campaign. The map produced from this campaign complements the 8-color base map (at an average resolution of 1 km/pixel) acquired during MESSENGER's primary mission by imaging Mercury's surface in a subset of the color filters at the highest resolution possible. The three narrow-band color filters are centered at wavelengths of 430 nm, 750 nm, and 1000 nm, and image resolutions generally range from 100 to 400 meters/pixel in the northern hemisphere.

Date acquired: July 08, 2014
Image Mission Elapsed Time (MET): 47121909, 47121901, 47121905
Image ID: 6643252, 6643250, 6643251
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: 2.83º
Center Longitude: 37.11º E
Resolution: 528 meters/pixel
Scale: Seuss is 64 km (40 miles) in diameter
Incidence Angle: 15.8º
Emission Angle: 12.2º
Phase Angle: 28.0º

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

Volcanic Vents North of Rachmaninoff Basin

This image, located north of Rachmaninoff, features a possible volcanic vent to the east and an expanse of terrain that appears blue in this color view to the west. The depression's orange-yellow color and irregular shape are similar to other possible volcanic vents on Mercury. To the west of the large vent is a crater with an orange, irregularly shaped depression on its floor that may also be a vent. Vents on Mercury are indicative of explosive volcanism that was prevalent in Mercury's past.

This image was acquired as a high-resolution targeted color observation. Targeted color observations are images of a small area on Mercury's surface at resolutions higher than the 1-kilometer/pixel 8-color base map. During MESSENGER's one-year primary mission, hundreds of targeted color observations were obtained. During MESSENGER's extended mission, high-resolution targeted color observations are more rare, as the 3-color base map covered Mercury's northern hemisphere with the highest-resolution color images that are possible.

Date acquired: July 03, 2014
Image Mission Elapsed Time (MET): 46686728, 46686748, 46686732
Image ID: 6612580, 6612585, 6612581
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: 36.10°
Center Longitude: 54.93° E
Resolution: 215 meters/pixel
Scale: The crater with a possible vent on its floor is about 20 km (12.4 miles) in diameter.
Incidence Angle: 40.6°
Emission Angle: 39.4°
Phase Angle: 78.0°

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

Possible Volcanic Peak in Depression

Today's image is an anaglyph, which means if you have a pair of red-cyan glasses, you can see the image in 3D. While this peak, which is slightly over a kilometer tall, is located within a circular depression, it is much larger relative to the size of the depression than other central peaks that formed during impact cratering events on Mercury. Additionally, the feature has a distinctive red color signature, associated with sites of explosive volcanic eruptions on Mercury. Peaks such as this one are rare on Mercury, but there is a similar one nearby that also shares the same red color characteristics.

This image was 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: November 14, 2013
Image Mission Elapsed Time (MET): 26772351, 26772627
Image ID: 5197359, 5197360
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -8.50°
Center Longitude: 224.4° E
Resolution: 50 meters/pixel
Scale: This image is roughly 45 km (28 miles) across
Incidence Angle: 44.7°, 44.6°
Emission Angle: 14.2°, 24.6°
Phase Angle: 59.0°, 62.2°
Orientation: North is to the right, to enhance the 3D effect.

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

Scarlatti Crater

The peak-ring basin Scarlatti is seen at the center of this image. While Scarlatti has a typical peak ring in many respects, in the northeast section it transitions to a large (approximately 30 km) pit surrounded by high-reflectance material. This pit may be the site of past explosive volcanic activity.

This image was acquired as a targeted 11-color image set. Acquiring 11-color targets is a new campaign that began in March 2013 and that utilizes all of the WAC's 11 narrow-band color filters. Because of the large data volume involved, only features of special scientific interest are targeted for imaging in all 11 colors.

Date acquired: March 30, 2014
Image Mission Elapsed Time (MET): 38528557, 38528553, 38528551
Image ID: 6032934, 6032932, 6032931
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: 40.7°
Center Longitude: 258.9° E
Scale: Scarlatti basin is 132 km (82 miles) in diameter

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

Volcanic Vents Near Hesiod Crater

The fiery yellow spots that stand out against the lower reflectance plains in this image are a series of pyroclastic vents stretching from roughly -60° latitude, within the crater Hesiod, to about -51° latitude. These vents are believed to have been the origins of explosive eruptions, driven by volcanic gases. Though they can be found across Mercury, this region contains one of the largest clusters of vents on the planet.

This image was acquired as a targeted color observation. Targeted color observations are images of a small area on Mercury's surface at resolutions higher than the 1-kilometer/pixel 8-color base map. During MESSENGER's one-year primary mission, hundreds of targeted color observations were obtained. During MESSENGER's extended mission, high-resolution targeted color observations are more rare, as the 3-color base map covered Mercury's northern hemisphere with the highest-resolution color images that are possible.

Date acquired: August 02, 2013
Image Mission Elapsed Time (MET): 17789351, 17789371, 17789355
Image ID: 4558440, 4558445, 4558441
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: -52.65°
Center Longitude: 329.5° E
Resolution: 777 meters/pixel
Scale: This image is about 725 km (450 mi.) wide at the top.
Center Incidence Angle: 58.9°
Center Emission Angle: 59.2°
Center Phase Angle: 28.0°

Photo 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

Bright Impact Crater Deposits Near Matisse Crater

This image brings us back to the vicinity of Matisse, the subject of several recent Gallery images. The unnamed impact crater with the bright pyroclastic deposit on its southern floor also has two arcuate scallops on its northern wall. These were the sites of massive landslides that took place when the oversteepened crater wall collapsed. The ultimate cause of the collapse is the topography of the area where the crater formed: the northern part of the crater formed on the wall of Matisse.

This image was acquired as part of MDIS's high-resolution albedo base map. The best images for discerning variations in albedo, or brightness, on the surface are acquired when the Sun is overhead, so these images typically are taken at low incidence angles. The albedo base map covers Mercury's surface at an average resolution of 200 meters/pixel.

Date acquired: April 05, 2012
Image Mission Elapsed Time (MET): 242124773
Image ID: 1609270
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -22.85°
Center Longitude: 267.3° E
Resolution: 196 meters/pixel
Scale: The crater with the bright floor is about 70 km (44 mi.) in diameter
Incidence Angle: 40.8°
Emission Angle: 30.0°
Phase Angle: 70.8°

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

Hollows and Pyroclastic Deposits in a Crater Near Caloris Basin

Today's image features several craters near the eastern edge of the Caloris basin. The larger craters have excavated low reflectance material, and both have hollows forming within their floors. Reddish deposits that exhibit a spectral signature similar to pyroclastics occur in the northeastern quadrant of this scene, suggesting that this region may have once been the site of explosive volcanism.

This image was acquired as a targeted high-resolution 11-color image set. Acquiring 11-color targets is a new campaign that began in March 2013 and that utilizes all of the WAC's 11 narrow-band color filters. Because of the large data volume involved, only features of special scientific interest are targeted for imaging in all 11 colors.

Date acquired: October 24, 2013
Image Mission Elapsed Time (MET): 24470528, 24960452, 24470516
Image ID: 5033545, 5068359, 5033542
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: 23.72°
Center Longitude: 179.1° E
Resolution: 260 meters/pixel
Scale: The larger crater near the top of the image is approximately 54 km (33.5 mi.) in diameter.
Incidence Angle: 24.8°
Emission Angle: 8.4°
Phase Angle: 33.2°

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

Southwestern Rim of Caloris Basin

This image shows an area of the southwestern rim of the Caloris impact basin. The small hills in the lower left are part of the rim units, and the smooth surface to the right is part of the smooth plains within the basin. The scene lies right on a color boundary between darker rim material and higher-reflectance plains. Small hollows are found on the top of the hills, and small lobate scarps cross the area. The famous kidney-shaped pyroclastic vent is just to the east (right), out of the scene.

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: July 03, 2013
Image Mission Elapsed Time (MET): 15137794
Image ID: 4370103
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 22.04°
Center Longitude: 143.6° E
Resolution: 42 meters/pixel
Scale: The scene is about 57 km (35 mi.) across
Incidence Angle: 68.7°
Emission Angle: 31.8°
Phase Angle: 100.1°
North is up in this image.

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

Contrast Stretch of Matisse Crater

Today's feature is the 748-nm filter image from from the October 21, 2013 color presentation. The graphs underneath the image illustrate a basic principle of image processing: the contrast stretch. A computer is typically capable of displaying a black and white ("greyscale") image as a series of pixels with 256 levels of brightness, between 0 (black) and 255 (white). Therefore, in order to be displayed, the numerical values of the image must be "stretched" to cover the range 0 to 255. In the case of a calibrated MDIS image, the image values are in physical units of reflectance -- that is, the percentage of incident light that the surface reflects. The graphs underneath the image are histograms. The x-axis is the range of pixel values that occur in the image, and the y-axis is the frequency of the values. The histogram on the lower left shows that the range of reflectance values in the image is from about 0.02 to 0.07 (or about 2% to 7% reflectance). The plot peaks at about 0.04, indicating that the most frequent pixel value is about 0.04. The plot on the lower right shows how the input pixel values have been scaled from 0 to 255 to produce the image above. Note that to display a color image (i.e., in red-green-blue), each of the three input color planes is stretched separately.

This image was acquired as a high-resolution targeted color observation. Targeted color observations are images of a small area on Mercury's surface at resolutions higher than the 1-kilometer/pixel 8-color base map. During MESSENGER's one-year primary mission, hundreds of targeted color observations were obtained. During MESSENGER's extended mission, high-resolution targeted color observations are more rare, as the 3-color base map covered Mercury's northern hemisphere with the highest-resolution color images that are possible.

Date acquired: October 21, 2012
Image Mission Elapsed Time (MET): 259266840
Image ID: 2803280
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: -23.00°
Center Longitude: 268.4° E
Resolution: 674 meters/pixel
Scale: The scene is about 890 km (553 mi.) across
Incidence Angle: 45.6°
Emission Angle: 33.5°
Phase Angle: 78.7°
North is up in this image.

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

Catullus Crater

Named for the Roman poet Gaius Valerius Catullus, this impact crater, 100 km (62 mi.) in diameter, has a smoothly textured floor like that seen elsewhere on Mercury. The western portion of the floor (right) abuts against the inner, terraced wall of the crater (middle), which is bordered by the surrounding, older terrain (left). Scientists know of two ways to render the floor of a crater smooth: impact melt or volcanism. It can be difficult to differentiate the two processes, however, and so the nature of the smooth material within Catullus remains unknown. However, in a larger view a depression can be seen in the center of Catullus that may be volcanic in nature -- and so too might the floor of the crater itself.

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: August 8, 2013
Image Mission Elapsed Time (MET): 18306428
Image ID: 4595268
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 21.98°
Center Longitude: 293.43° E
Resolution: 39 meters/pixel
Scale: The field of view in this image is approx. 40 km (25 mi.) across
Incidence Angle: 68.1°
Emission Angle: 3.5°
Phase Angle: 71.6°
North is down in this image.

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

Pyroclastic Deposits at Matisse Crater

This color view of the vicinity of Matisse crater, seen in an early Gallery image from MESSENGER's first flyby of Mercury in 2008. Two unnamed craters formed tangentially to the rim of Matisse (one just inside the rim, and one just outside). These craters have bright orange deposits on their floors. High reflectance and a greater-than-average ("red") spectral slope create the orange appearance in this color presentation. Such color characteristics are found at many other locations on Mercury where pyroclastic volcanic eruptions took place.

This image was acquired as a high-resolution targeted color observation. Targeted color observations are images of a small area on Mercury's surface at resolutions higher than the 1-kilometer/pixel 8-color base map. During MESSENGER's one-year primary mission, hundreds of targeted color observations were obtained. During MESSENGER's extended mission, high-resolution targeted color observations are more rare, as the 3-color base map covered Mercury's northern hemisphere with the highest-resolution color images that are possible.

Date acquired: October 21, 2012
Image Mission Elapsed Time (MET): 259266820, 259266840, 259266824
Image ID: 2803275, 2803280, 2803276
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: -23.00°
Center Longitude: 268.4° E
Resolution: 674 meters/pixel
Scale: The scene is about 890 km (553 mi.) across; Matisse crater is about 186 km (116 mi.) in diameter
Incidence Angle: 45.6°
Emission Angle: 33.5°
Phase Angle: 78.7°
North is up in this image.

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

Anaglyph of Volcanic Vent Near Discovery Rupes

Like yesterday's image, and the one from last week, today's image features the same potential volcanic vent. However, today's image is actually a combination of two additional images that were taken by the spacecraft 255 seconds apart. During that time of just over 4 minutes, the spacecraft had moved enough to provide slightly different viewing angles of the same surface, enabling this 3D representation to be made. Find a pair of red-cyan glasses to view the 3D image, and the image has been rotated such that north is to the left to enhance the 3D effect.

This image was 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 02, 2013
Image Mission Elapsed Time (MET): 15108910, 15109165
Image ID: 4368031, 4368047
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 24.28°
Center Longitude: 148.3° E
Resolution: 44 meters/pixel
Scale: This image is 40 km (25 miles) across
Incidence Angle: 72.2°
Emission Angle: 26.1°, 32.9°
Phase Angle: 98.2°, 96.3°

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

Possible Volcanic Vent Near Discovery Rupes

Different lighting conditions can reveal different insights into Mercury's surface. Check out this dramatic example of Discovery rupes. Today's image shows the same proposed volcanic vent that was featured last week, but this image was obtained with the Sun more nearly overhead. With this new view, you can see areas of the surface that were previously hidden in shadows.

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: June 06, 2013
Image Mission Elapsed Time (MET): 12831164
Image ID: 4206165
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 24.34°
Center Longitude: 148.3° E
Resolution: 28 meters/pixel
Scale: The diameter of the small crater to the left of the proposed vent is about 5 km (3 miles)
Incidence Angle: 26.7°
Emission Angle: 8.5°
Phase Angle: 35.2°

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

Volcanic Vents North of Rachmaninoff Crater

This beautiful view of the volcanic vents located to the north of the Rachmaninoff basin gives a new perspective on the area. At center, a vent is located within the bright pyroclastic deposit that is thought to have erupted from the vent. An older vent is also seen toward the bottom right as an irregularly shaped depression, though it has no clear surrounding deposit. The oblique angle of the image allows a view of the eastern walls of these features.

Date acquired: August 23, 2013
Image Mission Elapsed Time (MET): 19543205
Image ID: 4683301
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: 35.77°
Center Longitude: 63.90° E
Scale: The central vent is approximately 36 km (22 mi.) across.

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

Possible Volcanic Vent Near Discovery Rupes

The Caloris basin contains a complex mix of impact, tectonic, and volcanic features. At center-right, the elongate depression may be a volcanic vent within the basin. This feature highlights the ambiguity that sometimes arises in discerning whether a depression is due to an impact or a volcanic event, as both can leave elongate depressions. One clue that might point to volcanism is the depression's slightly irregular shape; another is the apparent lack of a rim of impact ejecta that is raised above the baseline level of the surrounding terrain.

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: June 30, 2013
Image Mission Elapsed Time (MET): 14936140
Image ID: 4355811
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 24.18°
Center Longitude: 148.1° E
Resolution: 48 meters/pixel
Scale: The proposed vent is 17.9 km (11.1 mi.) across
Incidence Angle: 66.0°
Emission Angle: 50.3°
Phase Angle: 115.4°

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

Impact Craters and a Contractional Ridge Inside Copland Crater

Located in Copland crater, this image consists of three small unnamed impact craters and a contractional ridge that was partly destroyed by the two superimposed impact craters at the center. At one point extensive volcanic eruptions took place within Copland, forming a smooth surface. As the lava cooled it contracted, causing fractures and ridges to form. Images such as this give scientists a better understanding of the processes that accompany flood volcanism on Mercury and other planetary bodies.

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: September 13, 2011
Image Mission Elapsed Time (MET): 224423780
Image ID: 755249
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 38.00°
Center Longitude: 72.66° E
Resolution: 35 meters/pixel
Scale: The largest crater is about 9 km (5.5 mi.) in diameter.
Incidence Angle: 75.9°
Emission Angle: 0.2°
Phase Angle: 75.7°

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