First Image of Messenger's Extended Mission

One year ago, MESSENGER became the first spacecraft ever to orbit Mercury. On March 18, 2012, MESSENGER completed its one-year primary mission and began a yearlong extended mission that includes a number of new scientific observation campaigns. The image shown here was acquired yesterday and is the first of MESSENGER's extended mission.

Date acquired: March 18, 2012
Image Mission Elapsed Time (MET): 240541431
Image ID: 1531424
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 24.41°
Center Longitude: 6.77° E
Resolution: 42 meters/pixel
Scale: This image is approximately 43 kilometers (27 miles) across.
Incidence Angle: 28.95°
Emission Angle: 10.21°
Phase Angle: 29.40°

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

Deep Impact

Although Mercury is replete with impact craters, it can be difficult to gauge their size in a meaningful way. This oblique image shows an unnamed crater that lies within the Rachmaninoff basin. It is a simple crater, characterized by its bowl-like shape, and lacks the central peak or peak ring of larger, complex craters. The famous Meteor Crater in Arizona, though also a simple crater, is five times smaller in diameter! (North is towards the upper left corner of the image.)

Date acquired: February 09, 2012
Image Mission Elapsed Time (MET): 237254445
Image ID: 1371698
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 27.52°
Center Longitude: 54.40° E
Resolution: 30 meters/pixel
Scale: The crater in the center of the image is 7 km (4.4 miles) in diameter
Incidence Angle: 41.3°
Emission Angle: 40.1°
Phase Angle: 28.1°

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

Landslides in an Impact Crater

This impact crater, approximately 25 km (16 miles) in diameter, has been heavily modified by landslides. Portions of the crater's walls detached and slumped towards the floor, producing terraces along the wall, landslide deposits on the crater floor, and modifying the crater's outline from circular to irregular. The small bright spots on the landslide deposits (near the top of the image) may be hollows, similar to those seen in other impact craters on Mercury.

Date acquired: February 04, 2012
Image Mission Elapsed Time (MET): 236872479
Image ID: 1353311
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 19.43°
Center Longitude: 81.37° E
Resolution: 22 meters/pixel
Scale: The edges of this image are approximately 23 km (14 miles) long
Incidence Angle: 50.4°
Emission Angle: 9.3°
Phase Angle: 41.1°

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

Lobate Scarp

This image shows a lobate scarp in Mercury's northern hemisphere. Lobate scarps are believed to form when one block of crust thrusts up and over another, in response to the global contraction of Mercury as its core cooled and solidified. This scarp developed as the block of crust on the left of the image moved towards the right. North is to the bottom right of the image.

Date acquired: January 01, 2012
Image Mission Elapsed Time (MET): 233942639
Image ID: 1211937
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 26.86°
Center Longitude: 85.09° E
Resolution: 54 meters/pixel
Scale: The crater at the left of the image is approximately 20 km (12 miles) in diameter
Incidence Angle: 61.6°
Emission Angle: 54.0°
Phase Angle: 28.1°

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

Debussy Crater

Here we have two images of the impact crater named Debussy. The one on the left is from MESSENGER's monochrome base map. The one on the right is a complement from the stereo base map. Because of the differing viewing perspectives, the images can be combined to derive an elevation map (digital terrain model) of the surface.

The left image was acquired as part of MDIS's high-resolution surface morphology base map. The surface morphology base map will cover more than 90% of Mercury's surface with an average resolution of 250 meters/pixel (0.16 miles/pixel or 820 feet/pixel). Images acquired for the surface morphology base map typically have off-vertical Sun angles (i.e., high incidence angles) and visible shadows so as to reveal clearly the topographic form of geologic features. The right image was acquired as part of MDIS's high-resolution stereo base map. The stereo base map is used in combination with the surface morphology base map to create high-resolution stereo views of Mercury's surface, with an average resolution of 250 meters/pixel (0.16 miles/pixel or 820 feet/pixel) or better. During MESSENGER's one-year mission, the surface morphology base map is acquired during the first 176 days, and the second 176 days are used to acquire the complementary stereo base map, which includes the image here.

Left image:
Date acquired: July 31, 2011
Image Mission Elapsed Time (MET): 220581440
Image ID: 572963
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -34.04°
Center Longitude: 11.25° E
Resolution: 284 meters/pixel
Incidence Angle: 67.2°
Emission Angle: 35.2°
Phase Angle: 102.4°

Right image:
Date acquired: January 19, 2012
Image Mission Elapsed Time (MET): 235424544
Image ID: 1283627
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -33.95°
Center Longitude: 13.18° E
Resolution: 161 meters/pixel
Incidence Angle: 76.9°
Emission Angle: 23.3°
Phase Angle: 89.2°
Scale: Debussy crater has a diameter of about 80 km (50 mi.)

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

Solar Storm Effects

Watch space weathering happen! The recent solar storm had a dramatic effect on MESSENGER images of Mercury. In the image above, you can see bright streaks and speckles, with Mercury's surface faintly visible behind them. These streaks are energetic particles from the Sun hitting the camera's CCD. While great for illustrating the powerful solar event, images acquired during this period will have to be re-planned for later in the mission.

Date acquired: March 07, 2012
Image Mission Elapsed Time (MET): 239584591
Image ID: 1484381
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -36.55°
Center Longitude: 298.76° E

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

Derain Crater

This image, taken with the Wide Angle Camera (WAC), gives us a close-up look at Derain crater. Named for the twentieth century French artist André Derain, this crater was first viewed during MESSENGER's second flyby. Its unique dark collar is made up of low-reflectance material (LRM) exposed during the impact that formed the crater; this material is some of the darkest identified on Mercury and may have a mineralogical composition that is different from the surrounding terrain.

Date acquired: February 10, 2012
Image Mission Elapsed Time (MET): 237382607
Image ID: 1377852
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 5 (628 nanometers)
Center Latitude: -8.97°
Center Longitude: 19.19° E
Resolution: 501 meters/pixel
Scale: Derain crater is 190 km (118 miles) in diameter
Incidence Angle: 8.9°
Emission Angle: 51.4°
Phase Angle: 55.1°

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

Rachmaninoff Impact Basin

This image, taken with the Wide Angle Camera (WAC), provides a master class in Mercury surface features and the geologic processes that formed them. The image shows a portion of Rachmaninoff, a double-ring basin named for the early twentieth century Russian composer, pianist and conductor Sergei Rachmaninoff. In this region, we see the remnants of an inner peak ring, with hollows dusting the tops of the peaks in both the inner and outer rings. Also visible is the basin's main rim scarp beginning in the left corner of the image and extending to the southeast. The crater floor contains a number of regions of high-reflectance material, as well as polygonal valleys called graben (located near the top of the image, at the basin's center). Graben are formed by forces pulling apart the surface; these extensional forces are in contrast to the tectonic contraction we typically see all over Mercury and may be related to cooling of the smooth volcanic plains that cover the floor.

Date acquired: February 06, 2012
Image Mission Elapsed Time (MET): 237042001
Image ID: 1361459
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: 25.53°
Center Longitude: 57.51° E
Resolution: 136 meters/pixel
Scale: This image is 238 km (148 miles) wide from left corner to right corner.
Incidence Angle: 37.9°
Emission Angle: 36.3°
Phase Angle: 74.2°

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

Lobate Scarp Within Rembrandt Basin

This image, taken with the Narrow Angle Camera (NAC), shows a simple crater within Rembrandt Basin. Running through the crater is a lobate scarp, formed as Mercury's large iron core cooled and contracted, generating compressive forces that pushed one section of the planet's crust over the top of another section. Determining the geometry of such scarps and the time periods when deformation occurred can help scientists to understand the thermal history of the planet.

Date acquired: February 05, 2012
Image Mission Elapsed Time (MET): 236961590
Image ID: 1357377
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -29.79°
Center Longitude: 83.26° E
Resolution: 184 meters/pixel
Scale: The large crater at the bottom of the image is about 59 km (37 miles) in diameter.
Incidence Angle: 57.8°
Emission Angle: 39.0°
Phase Angle: 78.2°

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

Sher-Gil Crater

Impact craters serve as probes into a planet's subsurface, excavating and exposing material from depth that would be otherwise unobservable. Thus the study of impact crater deposits can help to elucidate the geological history of the target region. In this image, the crater Sher-Gil has exposed low-reflectance material, particularly in its eastern wall and at two concentrated points on the north and south rim. Younger, bright features called hollows dot the dark parts of the crater.

Date acquired: December 01, 2011
Image Mission Elapsed Time (MET): 231267850
Image ID: 1082997
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -45.06°
Center Longitude: 135.3° E
Resolution: 102 meters/pixel
Scale: Sher-Gil crater is about 76 km (47 mi.) in diameter
Incidence Angle: 59.6°
Emission Angle: 15.9°
Phase Angle: 65.0°

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

Unnamed Complex Crater with Impact Melt

This image, taken with the Narrow Angle Camera (NAC), gives us a spectacular close-up look at an unnamed complex crater in Mercury's northern hemisphere. At the top we see wall terraces containing ponds of impact melt. At the bottom is the crater's central peak, which displays bright material and possibly hollows near its summit.

Date acquired: February 01, 2012
Image Mission Elapsed Time (MET): 236617390
Image ID: 1340969
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 50.84°
Center Longitude: 93.60° E
Resolution: 20 meters/pixel
Scale: The edges of the image are about 10 km (6 mi.) long.
Incidence Angle: 66.6°
Emission Angle: 10.8°
Phase Angle: 55.7°

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

Bright Rayed Crater

This image, taken with the Wide Angle Camera (WAC), shows a bright rayed crater in Mercury's southern hemisphere. The rays, created when target material was ejected out onto the surface during the impact that formed the crater, will gradually fade over time due to the effects of Mercury's harsh space environment. The crater is deep enough that the local surface layers were penetrated, exposing low reflectance material (LRM) beneath.

Date acquired: February 06, 2012
Image Mission Elapsed Time (MET): 237000734
Image ID: 1359421
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 9 (996 nanometers)
Center Latitude: -17.70°
Center Longitude: 67.69° E
Resolution: 414 meters/pixel
Scale: The central rayed crater is 24 km (15 miles) in diameter.
Incidence Angle: 41.2°
Emission Angle: 12.0°
Phase Angle: 52.3°

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

Southern Anonymity

This scene captures an area of Mercury's southern hemisphere where none of the craters have yet had names approved by the International Astronomical Union. A variety of terrain types are found in this region: rugged heavily cratered older surfaces, smooth plains on crater floors, and younger bright-rayed craters.

Date acquired: September 20, 2011
Image Mission Elapsed Time (MET): 225001789
Image ID: 783910
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -55.50°
Center Longitude: 16.58° E
Resolution: 361 meters/pixel
Scale: The edges of this image are about 360 km (220 mi.) long
Incidence Angle: 57.9°
Emission Angle: 1.3°
Phase Angle: 58.9°

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

Beethoven Basin Elevation Map

This elevation map of the Beethoven basin is color-coded to show the height of features on Mercury's surface. Mercury lacks a "sea level," so the zero-point reference elevation is defined to be the mean planetary radius of 2440 km. Blue areas, such as within Bello crater on the floor of Beethoven, have negative elevations. The red and white areas to the southwest are more than 8 km higher than the lowest points in this area.

Center Latitude: -20°
Center Longitude: 236° E
Scale: Beethoven basin is ~650 km (404 miles) in diameter
Image information: A digital terrain model (DTM) derived from Mercury Dual Imaging System (MDIS) stereo images. The lateral spacing is 330 meters and the map is in stereographic (conformal) projection. The image is taken from abstract number 1913 submitted to the 2012 Lunar and Planetary Science Conference, by Frank Preusker and colleagues.

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

Hesiod Crater

The crater at the western corner of this image is Hesiod. The northern and eastern parts of Hesiod's rim are marked by irregular depressions. These depressions are thought to be vents from which explosive (pyroclastic) volcanic eruptions originated. The high-reflectance areas on the wall of the crater just to the northeast of Hesiod and at the top of the image share color characteristics with other pyroclastic deposits known on Mercury. Pyroclastic eruptions are driven by volatile compounds, and MESSENGER has revealed that Mercury has a higher abundance of volatile elements than was previously expected.

Date acquired: September 07, 2011
Image Mission Elapsed Time (MET): 223922395
Image ID: 730933
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: -57.84°
Center Longitude: 329.6° E
Resolution: 193 meters/pixel
Scale: Hesiod crater is about 100 km (62 miles) in diameter
Incidence Angle: 62.7°
Emission Angle: 21.7°
Phase Angle: 84.5°

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

Firdousi Crater

Firdousi is a relatively fresh impact crater approximately 96 kilometers (60 miles) in diameter. Its abundant secondary craters dominate the surroundings, and many have haloes of high-reflectance, relatively blue ejecta.

Date acquired: August 14, 2011
Image Mission Elapsed Time (MET): 221844487, 221844483, 221844479
Image ID: 632390, 632389, 632388
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: 4.19°
Center Longitude: 65.30° E
Resolution: 204 meters/pixel
Scale: Firdousi is approximately 96 kilometers (60 miles) in diameter
Incidence Angle: 37.0°
Emission Angle: 14.6°
Phase Angle: 51.7°

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

Checkov and Schubert Basins

Two prominent basins, Chekhov at the upper left and Schubert at lower right, are both just under 200 km in diameter but have very different appearances. Chekhov has a prominent peak ring and its older age is reflected in the numerous craters that have battered its rim and floor. Schubert's floor is smooth with only a hint of its peak ring peeking through.

Date acquired: October 31, 2011
Image Mission Elapsed Time (MET): 228589200, 228589220, 228589204
Image ID: 956051, 956056, 956052
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: -37.80°
Center Longitude: 303.8° E
Resolution: 655 meters/pixel
Scale: Scene is approximately 700 km (435 miles) across
Incidence Angle: 71.1°
Emission Angle: 15.9°
Phase Angle: 86.8°

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

De Graft Crater and Rays from Hokusai

A colorful view of a complex region is shown in this image. The high-reflectance and hollow-filled floor of de Graft crater is visible at center left, and a similar high-reflectance smaller crater is located to the northeast. Streaking across the scene from north to south are rays from Hokusai crater, located over 1,500 km away.

Date acquired: September 22, 2011
Image Mission Elapsed Time (MET): 225143097, 225143117, 225143101
Image ID: 790098, 790103, 790099
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: 24.00°
Center Longitude: 6.67° E
Resolution: 421 meters/pixel
Scale: De Graft crater is approximately 68 km (42 miles) in diameter
Incidence Angle: 26.8°
Emission Angle: 22.5°
Phase Angle: 39.3°

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

Brontë and Degas Craters

This image shows a colorful view of Brontë (the large crater in the top right corner) and Degas (the blue-hued crater atop Brontë). These craters are located in Sobkou Planitia, a plains region formed through past volcanic activity.

Date acquired: December 12, 2011
Image Mission Elapsed Time (MET): 232160712, 232160708, 232160704
Image ID: 1125985, 1125984, 1125983
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: 36.44°
Center Longitude: 231.5° E
Resolution: 231 meters/pixel
Scale: Degas crater is 52 km (32 miles) in diameter
Incidence Angle: 59.7°
Emission Angle: 25.2°
Phase Angle: 85.0°

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

Shakespeare Impact Basin

For Valentine's Day, it seems appropriate to feature Shakespeare basin, named for the English poet and playwright and author of a famous collection of sonnets, some focusing on love. "Shall I compare thee" to other large basins on Mercury? If so, check out Rembrandt, Tolstoj, Rachmaninoff and Beethoven.

This mosaic was assembled from eight images that were acquired as part of MDIS's high-resolution surface morphology base map. The surface morphology base map will cover more than 90% of Mercury's surface with an average resolution of 250 meters/pixel (0.16 miles/pixel or 820 feet/pixel). Images acquired for the surface morphology base map typically have off-vertical Sun angles (i.e., high incidence angles) and visible shadows so as to reveal clearly the topographic form of geologic features.

Date acquired: April 26 - 28, 2011
Image Mission Elapsed Time (MET): 212372542, 212415875, 212416002, 212459333, 212459461, 212459565, 212502921, 212503025
Image ID: 181841, 183945, 183946, 185952, 185953, 185954, 188123, 188124
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: 48.5°
Center Longitude: 208° E
Resolution: 240 meters/pixel
Scale: Shakespeare basin has a diameter of 400 km (250 miles)
Incidence Angle: 73°
Emission Angle: 0.6°
Phase Angle: 75°

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