Data Dated June 2011MESSENGER since April 2011 has been working in orbit around Mercury as he had reached there on March 17th, 2011 by 9 a.m. EDT through a insertion maneuver. After fuel depletion, the mission was eventually slammed unto Mercury's surface on April 30th, 2015!
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First science data returned by MESSENGER are shaking many of earlier ideas about Mercury. In terms of surface features, first data have revealed that bright, patchy deposits on some crater floors already observed but unexplained are clusters of rimless, irregular pits often surrounded by diffuse halos of higher-reflectance material, and they are found associated with central peaks, peak rings, and rims of craters. They might be young and hinting to a more abundant than expected volatile component in Mercury's crust. In terms of Mercury's surface composition, the magnesium/silicon, aluminum/silicon, and calcium/silicon ratios averaged over large areas of the planet's surface show that, unlike the surface of the Moon, Mercury's surface is not dominated by feldspar-rich rocks. Substantial amounts of sulfur also have been observed with sulfide minerals likely present, suggesting that the original building blocks from which Mercury was assembled may have been less oxidized than those that formed the other terrestrial planets, and it has potentially important implications for understanding the nature of volcanism on Mercury. The importance of volcanism in plains formation in the planet’s history is larger than thought. The northern polar regions of Mercury have been mapped and shown a broad area of low elevations. Also radar data from MESSENGER are consistent with that polar deposits exist in the polar craters as they might consist of water ice and perhaps other ices preserved, like on our Moon, on the cold, permanently shadowed floors of high-latitude impact craters. Energetic events made of burst of energetic particles are being seen almost like clockwork in Mercury Earth-like magnetosphere. Such bursts had been one of the major discoveries made by the Mariner 10 mission as it was puzzling that MESSENGER had not detected any during its three flybys
 | Major-element composition of Mercury surface materials as a comparison with the inner solar system planets Venus excepted. picture courtesy NASA |
 | Magnetic field lines differ at Mercury's north and south poles. picture courtesy NASA |
 | Locations of energetic electron events relative to Mercury’s magnetic field. picture courtesy NASA |
 | The mounds in this image are the central peak of an unnamed crater as such central peaks are of great interest because they expose material that originally resided at depth. picture courtesy NASA/Johns Hopkins Applied Physics Laboratory/Carnegie Institute of Washington |
 | The lower left portion of this image shows an area of smooth plains as chains of secondary craters can be identified cutting across the middle of the image or a crater with a strong wall seen to the lower right. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Mercury terminator shown in color which characteristic double-ringed craters and scarps. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | The various features present in this color image dated June 2011, Qi Baishi, Hovnatanian, Kalidasa, and Tolstoj, show Mercury's scarred and variable surface. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | This image shows a large crater in Mercury's southern hemisphere that has not yet been assigned a name. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Beagle Rupes, the arcuate ridge seen in this picture, is one of the tallest and longest scarps on Mercury and seen in July 2011. It is seen deforming and shortening the elliptical impact crater Sveinsdóttir in the bottom left corner of the image. Beagle Rupes and other scarps on Mercury are thought to be the surface expressions of thrust faults that formed from contraction as the planet's interior cooled. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
MESSENGER continues beaming pictures from Mercury
 | Large Rembrandt basin is seen left as in contrast to the relatively darker material surrounding Rembrandt, Amaral crater and its bright rays can be seen on the right. Rembrandt basin is an area of particular scientific interest due to its large size, young age, and extensional and contractional characteristics. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | A trail of small craters. Such secondary crater chains are formed when the ejecta from a primary impact fall in the surrounding area. Also visible in this image are smooth plains, formed by volcanism that has filled in a large impact crater. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | A crater is seen situated at the edge of the larger Oskison crater located in the plains north of Caloris basin. A detailed look at the crater reveals its terraced walls, smooth floor, and its superposition on Oskison's shadowed rim. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
Orbital data reveal that Mercury's magnetic field is offset far to the North of the planet's center, by nearly 20 percent of Mercury's radius. Relative to the planet's size, this offset is much more than in any other planet, and accounting for it will pose a challenge to theoretical explanations of the field. This means also that the magnetic field in the southern hemisphere should be a lot weaker than it is in the North, with a difference of 3.5 times. Hence energetic particles, solar wind, and high-energy electrons will preferentially impact the surface in the South and to asymmetries in sources for Mercury's exosphere and in the discoloration of the surface by charged particles. Mercury tenuous exosphere of gas is generated and maintained by the interaction of the space environment with the planet's surface as some discrepancies about how much magnesium and calcium are found on the night side might question the usual thought that those were knocked out from the day side and brought into the night side by the solar wind pressure. Mercury magnetosphere indeed would couple with the interplanetary field to direct solar wind ions directly to the nightside albeit that explanation is not sufficient however. Also scientists have observed a unexplained enhanced concentration of calcium at the equator near dawn, a pattern that appears to be a persistent feature in the exosphere as such dawn enhancements are not observed for magnesium, albeit chemically similar to calcium. Sodium is the most important ion concentrated near Mercury's poles as likely liberated by solar wind in a manner comparable to which auroras are generated at Earth. Someone standing on Mercury's nightside at the right time of year would see a faint orange glow, the light of the planet's sodium tail. Helium is also found in the entire volume of the magnetosphere as delivered from the Sun by the solar wind. Such a weak magnetosphere provides the planet very little protection from the solar wind and extreme space weather must be a continuing activity at the surface of the planet closest to the Sun. After its first Mercury solar day in orbit MESSENGER has nearly completed two of its primary global imaging goals, a monochrome map at 250 meters per pixel and an eight-color, 1 kilometer per pixel color map as these maps cover the entire planet under uniform lighting conditions. Broad expanses of plains across the planet already seen by the Mariner 10 mission likely were formed through volcanism, which played a important role in shaping Mercury's crust. MESSENGER data show how volcanic rocks dominate much of Mercury's crust, even in regions that are geologically complex and where impact cratering has destroyed many of the original surface features. Lavas are locally as thick as 1.2 miles (2 kilometers) as vents, measuring up to 16 miles (25 kilometers) appear to be the source of some of the tremendous lava flows. Lava flows also eroded the substrate, carving valleys and creating teardrop-shaped ridges. Mercury, on the other hand, lacks of iron in the silicate minerals of the surface rocks, which is a main difference to most planetery crusts known until now. Sulfur is present. 'Hollows' at last, or very bright and blue small, shallow, irregularly shaped depressions that are often found in clusters on craters floor and central mountain peaks, are a variety of pits which still could be actively forming today thus a active Mercury! Potassium, that vaporizes at a relatively low temperature is present. Mercury has a volatile inventory similar to Venus, Earth, and Mars, and much larger than that of the Moon. It possesses a much higher mass fraction of iron metal than Venus, Earth, or Mars as observations hint that Mercury's surface composition is similar to that expected if the planet's bulk composition is broadly similar to that of highly reduced or metal-rich chondritic meteorites, a material that is left over from the formation of the solar system. A possible relationship is though to exist between the formation of explosive volcanic deposits and hollows. The knowledge gained about Mercury is helping to sharpen the mission goals of the 2014, European and Japanese ESA-JAXA BepiColombo mission
 | MESSENGER has discovered a unexpected class of shallow, irregular depressions (yellow arrows). Some of the depressions have bright interiors and halos (white arrows). The science team is referring to these features as "hollows" in order to distinguish them from other types of non-impact depressions found on Mercury like volcanic vents, or collapse pits. The origin of hollows is not certain, but may involve loss of volatile material, like the sublimation of material when exposed by a impact which created a crater. picture courtesy AAAS/Science |
 | These images show Mercury and the nearside of the Moon at their correct relative brightness. On average, the surface of Mercury is about 15% darker at visible wavelengths than is the nearside of the Moon. This is perplexing to planetary scientists because Mercury's surface is lower in iron, the element in lunar rocks that contributes most to absorbing light. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Here is a small pond of impact melt that was ejected from a crater just out of view. The melt ponded in this low, forming a smooth surface!. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | That rimless, non-circular depression lies along the inner margin of the Caloris basin. It is the vent of a small, explosive volcano, similar to other volcanic vents on Mercury! The small number of superposed craters indicates that this feature is relatively young. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | The central peaks of Eminescu Crater are revealed here at high resolution, showing off a remarkable view of hollows! Some of those have coalesced into larger formations. A fine Mercurian horizon also is seen in the background. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Another view of hollows in a crater. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
MESSENGER continues beaming pictures from Mercury. By March 2012 further, most recent developments in terms of the MESSENGER mission are that the first precise model of Mercury's gravity field has been developed which, when combined with topographic data and the planet's spin state, sheds light on the planet's internal structure. Mercury's core represents about 85 percent of the planetary radius, even larger than previous estimates. Despite the planet's small size subtle dynamical motions measured from Earth-based radar, combined with MESSENGER's newly measured parameters of the gravity field and the characteristics of Mercury's internal magnetic field signify an active core dynamo, thus indicating that the planet's core is at least partially liquid. Such discoveries have importance for how Mercury's magnetic field is generated and for understanding how the planet evolved thermally. The first-ever precise topographic model of the planet's northern hemisphere on a other hand is showing that the spread in elevations is considerably smaller than those of Mars or the Moon with the most prominent feature a extensive area of lowlands at high northern latitudes that hosts the volcanic northern plains. Within this lowland region is a broad topographic rise that formed after the volcanic plains were emplaced. At mid-latitudes, the interior plains of the Caloris impact basin — 960 miles (1,550 km) in diameter — have been modified so that part of the basin floor now stands higher than the rim. The elevated portion appears to be part of a quasi-linear rise that extends for approximately half the planetary circumference at mid-latitudes. These features imply that large-scale changes to Mercury's topography occurred after the era of impact basin formation and large-scale emplacement of volcanic plains had ended. As far as the radar-bright deposits at the poles of Mercury are concerned, and assumed dominantly frozen water ice, images from MESSENGER show that all such features near Mercury's south and north poles are located in areas of permanent shadow, results which are consistent with the water-ice hypothesis but not definitive proof
 | That view of Kuiper crater shows the bright rays that extend out from this relatively young crater but also the redder color of Kuiper's ejecta blanket. That may be due to a compositionally distinct material excavated from depth by the impact that formed Kuiper. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Colorful view of Brontë (the large crater bottom left) and Degas (the blue-hued crater above Brontë). These craters are located in Sobkou Planitia, a plains region formed through past volcanic activity. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | A view of a complex region with the high-reflectance and hollow-filled floor of de Graft crater visible at center right, and a similar high-reflectance smaller crater is located to the southwest. Streaking across the scene from South to North are rays from Hokusai crater, a crater located over 930 miles (1,500 km away)!. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Here is a elongated pit inside basin Tolstoj, floor of which was likely flooded by lavas. The pit seen may have formed when magma withdrew from a shallow chamber, causing an unsupported area of the surface to collapse. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | A portion of Rachmaninoff, a double-ring basin is showing hollows dusting the tops of the peaks in both the inner and outer rings and graben (bottom). picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | In a unnamed complex crater in Mercury's northern hemisphere, we see wall terraces containing ponds of impact melt and a central peak, which displays bright material and possibly hollows near its summit . picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Firdousi carter is a relatively fresh impact crater approximately 60 miles (96 km) in diameter. Abundant secondary craters yielded from the impact dominate the surroundings with many featuring haloes of high-reflectance, relatively blue ejecta. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Two Mercurian basins are seen with Schubert at the upper left and Checkhov at lower right. Both are just under 124 miles (200 km) in diameter as Schubert with a smooth floor and young, and Chekhov a prominent peak ring and older as reflected in the numerous craters that have battered its rim and floor. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | A portion of the 73-mile (116-km) wide Abedin crater is showing many small troughs that are interpreted to be graben, a result of extensional stresses which may have resulted from the cooling and solidification of either impact melt or volcanic fill. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | A comparison of the internal structures of Earth and Mercury as currently understood based on the latest data from the MESSENGER mission. Mercury’s interior has a larger ratio of metallic core material to silicate rock material than the Earth. Mercury also appears to have a solid layer of iron sulfide that lies at the top of the core. The presence of this solid layer places important constraints on the temperatures within Mercury’s interior and may influence the generation of the planet’s magnetic field. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | The upper part of this view of Mercury's surface includes a swath of material that has reflectance that does not strongly increase toward longer wavelengths, a property described as relatively "blue" in color. The bluish material also has lower overall reflectance than Mercury's average surface. The terrain to the South and West has a more reddish color. A major puzzle of Mercury's geology is the identity of the particular rock types that correspond to these colors (the area is the one of craters Amaral, Neruda and Sher-Gil). picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | A view of the southern rim of the Caloris impact basin. The prominent reddish spots are associated with irregular depressions that are thought to be volcanic vents. The reddish deposits are probably formed of pyroclastic material ejected from the vents during explosive eruptions. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | A series of Mercurian craters is seen on this image. At the very bottom of the image is Tyagaraja Crater, with bright crater floor material, terraced walls, and central peaks, at a diameter of 60 miles (97km). By the center of the picture, crater Zeami is also featuring clear crater chains. North of Zeami is Sophocles, at a diameter of 88 miles (142km) with a smaller crater in its upper half and to the left of Sophocles the smaller Theophanes crater (diameter of 29 miles -46km) with orange tinted material surrounding its crater rim. Goya crater is seen to the right of Sophocles and of a similar size as Stevenson Crater is seen near the lower left quadrant of the image with a a distinctive "X" shape formed by crossing chains of secondary craters. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Rustaveli basin, in the northern hemisphere of Mercury has a smooth, filled floor with little weathering and a peak-ring structure. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | A scene between Moody and Amaral craters. The patch of dark blue Low Reflectance Material (LRM) in the lower center of the image and the bright rayed crater on the left are of interest. A small very dark crater is seen just above the latter. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | A pit seen inside Picasso crater is hypothesized to be a location where subsurface magma has evacuated, causing the surface to cave in. Such pits have been seen in various locations around Mercury too. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | A hummocky, pitted texture which could relate to past volcanic activity, and several troughs are visible in the center of crater Derain. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Abedin crater's towering central peaks. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Rachmaninoff is a spectacular double-ring basin on Mercury. Visible around the edges of the frame is a circle of mountains that make up Rachmaninoff's peak ring structure, which surrounds concentric troughs located on the basin floor. Both areas further are different in terms of materials . picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
MESSENGER found unusual groups of ridges and troughs on Mercury, which are assemblages of tectonic landforms. Unlike faulting which is due to contraction of Mercury when it colded only, such features are linked to horizontal stretching and pulling apart of crustal material. Families of extensional troughs, or graben, encircled by contractional wrinkle ridges arranged in circular rings have been observed, for example at Mercurian basins. They are also associated with ghost craters which are impact craters that have been flooded and buried by lava flows. The thin volcanic deposits overlying the rim of a fully buried impact crater serve to concentrate contractional forces, leading to the formation of a ridge ring that reveals the outline of the buried crater. The process at work combines eruption and rapid accumulation of very fluid lava flows into thick cooling units and Mercury high rate of global contraction, hence a characteristic seen at Mercury only (that topics does not have any illustration below)
New observations by the MESSENGER spacecraft by late 2012 has provided compelling support for the long-held hypothesis that Mercury harbors abundant water ice and other frozen volatile materials in its permanently shadowed polar craters. Spectrometer, reflectance and temperature models are part of the evidence. Presence of ice is due to the tilt of Mercury's rotational axis at almost zero so there are pockets at the planet's poles that never see sunlight. In 1991, the Arecibo radio telescope in Puerto Rico alreazdy had detected unusually radar-bright patches at Mercury's poles, spots that reflected radio waves in the way one would expect if there were water ice. Many of these patches corresponded to the location of large impact craters mapped by the Mariner 10 spacecraft in the 1970s'. But because Mariner saw less than 50 percent of the planet, planetary scientists lacked a complete diagram of the poles to compare with the images. Astronomers, from such recent results, think that ice at Mercury is buried beneath an unusually dark material across most of the deposits. A hydrogen-rich layer which could be water ice, more than tens of inches (centimeters) thick is extant beneath a thermally insulating superficial layer 10 to 20 inches (centimeters) thick. Ice and the insulating layer at Mercury likely was deposited by impacts of comets or asteroids. The dark material is likely a mix of complex organic compounds and may have been darkened further by exposure to the harsh radiation at Mercury's surface, even in permanently shadowed areas (that topics does not have any illustration below)
 | Seuss crater is relatively fresh, its floor contains impact melt and hollows as the impact has excavated materials with different color characteristics. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Hollows have been now found a relatively common feature on Mercury. Their sharp walls and well-defined features stand out against the muted background terrain, indicating they are substantially younger than their surroundings as that might hint too to that they are still forming today. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Such clustered and similar in size impact craters likely are secondary craters, which form when material from a larger primary crater is ejected and impacts the surrounding terrain. Those appear to originate from Fonteyn crater, just over 622 miles (1,000 km) to the East as that bright patch is a segment of one of Fonteyn's beautiful rays. Those secondary craters around 29 km (18 mi.) in diameter can also fly great distances away. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Many regions of Mercury's surface are comprised of relatively red and smooth terrain that appears to flood low-lying regions and partially fill or bury older craters. These smooth plains are thought to have been formed by volcanic activity that drowned the region in voluminous, low-viscosity lavas. . picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | That view of Mercury's limb provides a sense of what it would be like to fly over the innermost planet, and to look out the spacecraft window toward the horizon. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Young rayed impact crater Petipa formed near a boundary between intermediate terrain (brownish in this presentation, in low part of image) and low-reflectance material (dark blue, in the middle of the image). picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | After formation, craters often undergo modification as their walls partially collapse. Faulting that ring that crater's perimeter manifest as linear, sharp cliffs that face the crater interior. These have facilitated the downward movement of material from craters' walls. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Blue rays of Bek Crater dominate this scene, covering nearby craters with wisps of fresh material. Lermontov crater, seen at the top of the image, is thought to have been the site of explosive volcanic eruptions. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
100 percent of Mercury's surface was imaged as off March 2013
 | A global color map of Mercury's surface has been created by mosaicking thousands of sets of images obtained by the MESSENGER Wide Angle Camera (WAC). The colors shown here are related to variations in the spectral reflectance across the planet. This view captures both compositional differences and differences in how long materials have been exposed at Mercury's surface. Young crater rays, arrayed radially around fresh impact craters, appear light blue or white. Medium- and dark-blue areas are a geologic unit of Mercury's crust known as the 'low-reflectance material,' thought to be rich in a dark, opaque mineral. Tan areas are plains formed by eruption of highly fluid lavas. The large circular area near the top center is the Caloris impact basin, whose interior is filled with smooth, somewhat younger volcanic plains. Small orangish spots are materials deposited by explosive volcanic eruptions. As material is exposed to the harsh space environment around Mercury it darkens, generally. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | In a region of the southern rim of the large Caloris basin, a irregularly shaped depression is believed to be a pryoclastic volcanic vent, with a dark, low reflectance material (LRM). Most pyroclastic vents don't have this dark material, but other features do show small outcrops of it. picture courtesy NASA/Johns Hopkins University Applied Physics |
The International Astronomical Union (IAU) has named an impact crater on the planet after John Lennon, the British pop musician, member of the Beatles the most popular group of their generation. French romantic composer Hector Berlioz, American author Truman Capote, American sculptor Alexander Calder or Erich Maria Remarque, a German author best known for his novel All Quiet on the Western Front are also honored along with some other famed people
 | A fine view of young -1 billion years- Cunningham Crater with preserved terraces, well-defined central peak. picture courtesy NASA |
 | The swath of diffuse blue ejecta which emanates from Balanchine Crater might originate from a older impact as the new one redistributed the deposit. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | The bright floor of Lermontov Crater features large depressions found in the floor which have been interpreted as evidence for explosive volcanism, providing insight into Mercury's volcanic history. The surface within the crater also appears to have been altered by the formation of hollows. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | This image shows the complex crater Bartok as well as the limb of Mercury. picture courtesy NASA/Johns Hopkins University Applied Physics |
 | The irregularly shaped 19-mile (30-km)-diameter pit in the large crater at the bottom of that picture is thought to be related to shallow volcanic activity and to have formed due to the withdrawal of near-surface magma, causing the overlying surface to collapse. Such craters with interior volcanic pits are known as pit-floor craters. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | A striking boundary of smooth and rough terrain near Mercury's north pole which comes after crossing the expansive northern plains. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | A volcanic vent northeast of Rachmaninoff basin is showing some regions smooth, having been blanketed by very fine particles ejected explosively from the vent. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | Lessing crater can be seen in the lower left of this image and, instead of the typical central peak found in a complex crater on Mercury it sports a central pit, likely formed by volcanic activity. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | That view highlights the spectacular interior of Abedin crater as the crater floor is covered with molten rock melted by the impact event that formed the crater. Cracks that formed as this melt cooled are visible left. Particularly intriguing is the shallow depression that lies amidst the central peaks of the crater and may be volcanic in origin. picture courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
 | MESSENGER was slammed into Mercury’s surface at about 8,750 mph on April 30th, 2015 as the probe hit the side of the planet facing away from Earth. The mission had run out of propellant as a series of orbit correction maneuvers prepared the descent or the mission performed last studies of the magnetic anomalies at Mercury. picture courtesy NASA |
