skip to main |
skip to sidebar
MESSENGER was just 184 km above Mercury's surface when it snapped this view of a hollow in Ahmad Baba crater. The hollow is located on the south-facing slope of Ahmad Baba's peak ring (north is toward the upper-right corner in 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: May 12, 2014
Image Mission Elapsed Time (MET): 42186174
Image ID: 6293058
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 57.60°
Center Longitude: 231.5° E
Resolution: 6 meters/pixel
Scale: This image is approximately 7 km (4 miles) across
Incidence Angle: 70.8°
Emission Angle: 49.0°
Phase Angle: 80.0°
Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
One of our highest resolution views yet inside the beautiful Balanchine crater reveals the bright hollows that cover portions of the crater. (See also this lower resolution view taken in 2011, before Balanchine crater was named.) The hollows appear to reside not just on the floor, but on portions of the slumped crater walls as well.
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: April 18, 2014
Image Mission Elapsed Time (MET): 40112892
Image ID: 6145582
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 38.18°
Center Longitude: 175.1° E
Resolution: 27 meters/pixel
Scale: This image is approximately 28 km (17 miles) across
Incidence Angle: 39.9°
Emission Angle: 7.9°
Phase Angle: 41.1°
Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
The troughs of Raditladi are the focus of this high-resolution view inside the peak-ring basin. The troughs, which are largely concentric to the basin, formed through extensional stresses that caused portions of the floor to pull apart. Such extensional features are similar to those observed within Caloris. Some of the small, bright craters that dot Raditladi's floor may be secondaries from Fonteyn crater approximately 900 km away, whose rays appear to cross the basin.
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: April 30, 2014
Image Mission Elapsed Time (MET): 41150312
Image ID: 6219297
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 27.79°
Center Longitude: 119.4° E
Resolution: 38 meters/pixel
Scale: This scene is approximately 46 km (29 miles) across
Incidence Angle: 63.9°
Emission Angle: 33.0°
Phase Angle: 97.0°
Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
The large crater at the center-left of today's image is Liang Kai. Liang Kai (the crater) is about 140 km in diameter and is fairly old. Its walls and rim have been substantially eroded, and its interior has been filled with a flat expanse of plains material.
Liang Kai (the human) was a painter of China's Southern Song Dynasty who lived from about 1140 to 1210 CE. He painted with an abbreviated approach, employing the minimal number of brushstrokes needed to evoke his subjects. Liang Kai was sometimes called "Madman Liang." One of his famous paintings is of a celestial being walking in a drunken stupor.
At the top edge of the image can be seen the terraced walls and bright central peaks of Gainsborough, named for an English painter.
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: June 11, 2012
Image Mission Elapsed Time (MET): 247903483
Image ID: 1996320
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -39.3°
Center Longitude: 177.5° E
Resolution: 264 meters/pixel
Scale: The image is about 270 km (167 mi.) wide
Incidence Angle: 39.4°
Emission Angle: 35.8°
Phase Angle: 75.2°
North is toward the top of the image.
Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
In this image, we see a portion of a wrinkle ridge to the north of Gauguin crater, high in Mercury's northern volcanic plains. Wrinkle ridges are common on Mercury, but when imaged under high resolutions we get a more detailed view of these structures than before. For example, here we can see that the leading edge of the ridge is actually composed of several smaller edges. The contact between the ridge and the surrounding smooth plains is softened toward the bottom right of the image, but near the top-left that contact is sharper. Continued high-resolution imaging of Mercury's wrinkle ridges will allow scientists to more thoroughly describe their various shapes, which in turn will help us understand why the ridges formed in the first place.
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): 36741405
Image ID: 5906004
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 69.7°
Center Longitude: 261.6° E
Resolution: 12 meters/pixel
Scale: The field of view in this image is about 6 km (4 mi.) across
Incidence Angle: 75.0°
Emission Angle: 6.9°
Phase Angle: 81.9°
North is to the right in this scene.
Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Wrinkle ridges are tectonic landforms observed across all of Mercury's smooth plains deposits, and are often superposed by impact craters. Craters themselves are frequently surrounded by lobate-like ejecta deposits, which at first glance might look like tectonic structures. In this image, a lobate-like feature runs parallel to the northern margin of an unnamed crater 20 km (12 miles) in diameter. Whether this landform is tectonic or impact-related is not yet clear, but with continued high-resolution imaging of other, similarly sized craters, we might be able to tell.
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 6, 2014
Image Mission Elapsed Time (MET): 36395675
Image ID: 5881419
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 66.3°
Center Longitude: 281.8° E
Resolution: 12 meters/pixel
Scale: The field of view in this image is 14 km (9 mi.) across
Incidence Angle: 70.5°
Emission Angle: 0.3°
Phase Angle: 70.2°
North is to the right in this scene.
Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
As MESSENGER passes progressively closer to Mercury, we see ever more resolved features in the images the spacecraft returns. Here, at a pixel scale of 9 meters, we see the eastern portion of an unnamed crater 13 km (8 mi.) in diameter. The wall of the crater is replete with smaller, superposed craters, some of which appear elongate possibly because they impacted on the larger crater's inclined wall. Interestingly, there are bright spots on the sunlight portion of this crater's wall -- which is where we might expect hollows to form.
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 3, 2014
Image Mission Elapsed Time (MET): 36136338
Image ID: 5862963
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 56.3°
Center Longitude: 301.6° E
Resolution: 9 meters/pixel
Scale: The field of view in this image is 11 km (7 mi.) across
Incidence Angle: 59.3°
Emission Angle: 43.0°
Phase Angle: 102.3°
North is to the right in this scene.
Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
This high-resolution image reveals a few melt ponds, which appear smoother than the surrounding terrain. These melt ponds were deposited as ejecta from this crater, which lies off to the north (top) of this image.
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): 36770132
Image ID: 5908036
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 63.77°
Center Longitude: 254.7° E
Resolution: 12 meters/pixel
Scale: The elliptical melt pond is approximately 1 km (0.6 mi.) in length.
Incidence Angle: 72.5°
Emission Angle: 6.3°
Phase Angle: 78.9°
Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
This image is one of the highest-resolution MDIS observations to date! Many craters of varying degradation states are visible, as well as gentle terrain undulations. Very short exposure times are needed to make these low-altitude observations while the spacecraft is moving quickly over the surface; thus the images are slightly noisier than typical MDIS images.
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 15, 2014
Image Mission Elapsed Time (MET): 37173522
Image ID: 5936740
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 71.91°
Center Longitude: 232.7° E
Resolution: 5 meters/pixel
Scale: The image is approximately 8.3 km (5.2 mi.) across.
Incidence Angle: 79.4°
Emission Angle: 4.0°
Phase Angle: 83.4°
Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
This hill lies towards the edge of Mercury's expansive northern plains. The Sun was low in the sky (high incidence angle) when this image was acquired, resulting in a shadow approximately 3.3 km (2 miles) long. Using trigonometry and knowledge of the incidence angle, the height of the hill can be calculated: ~340 m (~0.2 mile). This hill might be the remnants of an old crater rim that was subsequently flooded. North is to the right of this image.
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 25, 2014
Image Mission Elapsed Time (MET): 38066727
Image ID: 6000245
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 83.92°
Center Longitude: 242.3° E
Resolution: 13 meters/pixel
Scale: This image is approximately 7 km (4.3 mi.) across.
Incidence Angle: 84.0°
Emission Angle: 1.9°
Phase Angle: 82.0°
Photo credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Do hollows form preferentially on crater walls that receive more direct sunlight? In the northern hemisphere, the northern walls of craters are frequently sunlit, while the southern walls receive more grazing sunlight and are more often in shadow. (In the southern hemisphere it is the opposite.) The greater solar heating experienced by the northern wall may be an important factor in the formation of hollows. Images like the one here can help answer this question and are an area of focus for MESSENGER's current low-altitude imaging campaign. See these two other examples of hollows in craters walls.
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: February 25, 2014
Image Mission Elapsed Time (MET): 35646241
Image ID: 5828285
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 42.92°
Center Longitude: 330.9° E
Resolution: 17 meters/pixel
Scale: This crater has a diameter of 12.5 kilometers (7.8 miles)
Incidence Angle: 43.5°
Emission Angle: 46.1°
Phase Angle: 30.1°
Photo credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Running diagonally across today's image, from the upper left to the lower right, is a wall of an ancient crater that encompasses the crater Purcell. Purcell and the larger crater are both ancient, as evidenced by the numerous small craters that cover them, including their walls. This high-resolution image reveals how the small craters that formed on the wall display some differences from those formed on the more level neighboring surfaces.
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: April 11, 2014
Image Mission Elapsed Time (MET): 39535979
Image ID: 6104625
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 81.25°
Center Longitude: 212.2° E
Resolution: 9 meters/pixel
Scale: This image is about 13 kilometers (8 miles) across.
Incidence Angle: 81.4°
Emission Angle: 36.3°
Phase Angle: 82.5°
Photo credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
Posts
