Latest Images from Mercury Orbit

[Waspie_Dwarf]

First Image Ever Obtained from Mercury Orbit

Release Date: March 29, 2011

Date acquired: March 29, 2011

Image Mission Elapsed Time (MET): 209877871

Image ID: 65056

Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)

Center Latitude: -62.1°

Center Longitude: 18.4° E

Resolution: 2.7 kilometers/pixel (1.7 miles/pixel)

Scale: Debussy has a diameter of 80 kilometers (50 miles)

Of Interest: Early this morning, at 5:20 am EDT, MESSENGER captured this historic image of Mercury. This image is the first ever obtained from a spacecraft in orbit about the Solar System's innermost planet. Over the subsequent six hours, MESSENGER acquired an additional 363 images before downlinking some of the data to Earth. The MESSENGER team is currently looking over the newly returned data, which are still continuing to come down. Tomorrow, March 30, at 2 pm EDT, attend the NASA media telecon to view more images from MESSENGER's first look at Mercury from orbit.

The dominant rayed crater in the upper portion of the image is Debussy. The smaller crater Matabei with its unusual dark rays is visible to the west of Debussy. The bottom portion of this image is near Mercury's south pole and includes a region of Mercury's surface not previously seen by spacecraft. Compare this image to the planned image footprint to see the region of newly imaged terrain, south of Debussy. Over the next three days, MESSENGER will acquire 1185 additional images in support of MDIS commissioning-phase activities. The year-long primary science phase of the mission will begin on April 4, and the orbital observation plan calls for MDIS to acquire more than 75,000 images in support of MESSENGER's science goals.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

[ninjadude]

Waspy,

is Debussy a more recent crater? Seems that there are few craters overlapping it's rays...

[Waspie_Dwarf]

Waspy,

is Debussy a more recent crater? Seems that there are few craters overlapping it's rays...

I'm certainly not an expert on planetary geology, but if I remember rightly bright craters and bright rays tend to be a sign that a crater is fairly recent (in geological terms).

The issue with the rays and craters overlapping is this: do the crater overlap the rays or do the rays overlap the craters? If there are craters which have obliterated parts of the rays then this would indicate that those craters are older than the rays and therefore older than Debussy. If, on the other hand, the rays cross over the top of the craters (the rays, of course, being formed by material ejected from Debussy at the time it was formed) then this would indicate that Debussy formed after these craters.

Of course the likelihood is that there will be a combination of craters both younger and older than Debussy but we can still look at whether the majority are younger or older.

I have looked at the image, and it's not easy for me (as a non-expert) to tell, but it looks to me like the majority of craters are older than Debussy, implying that it is (in comparison to the surrounding area)a relatively new impact crater.

[Waspie_Dwarf]

An Annotated Guide to the First Orbital Image

Release Date: March 30, 2011

Date acquired: March 29, 2011

Image Mission Elapsed Time (MET): 209877871

Image ID: 65056

Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)

Center Latitude: -62.1°

Center Longitude: 18.4° E

Resolution: 2.7 kilometers/pixel (1.7 miles/pixel)

Scale: Debussy has a diameter of 80 kilometers (50 miles)

Of Interest: This historic first orbital image of Mercury was acquired 37 years to the day after Mariner 10’s historic first flyby of the innermost planet. Labels have been added to indicate several craters that were named based on Mariner 10 images, as well as Debussy, Matabei, and Berkel, which were named based on MESSENGER flyby images. The surface contained in the white lines is terrain previously unseen by spacecraft, and the star indicates the location of the south pole.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

[Waspie_Dwarf]

Exploring the Rays of Debussy

Release Date: March 30, 2011

Date acquired: March 29, 2011

Image Mission Elapsed Time (MET): 209885555

Image ID: 65082

Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)

Center Latitude: -36.4°

Center Longitude: 16.1° E

Resolution: 300 meters/pixel (0.19 miles/pixel)

Scale: Debussy crater has a diameter of 80 kilometers (50 miles)

Of Interest: Bright rays, consisting of impact ejecta and secondary craters, spread across this NAC image and radiate from Debussy crater, located at the top. The image, acquired yesterday during the first orbit for which MDIS was imaging, shows just a small portion of Debussy's large system of rays in greater detail than ever previously seen. Images acquired during MESSENGER's second Mercury flyby showed that Debussy's rays extend for hundreds of kilometers across Mercury's surface. Debussy crater was named in March 2010, in honor of the French composer Claude Debussy (1862-1918).

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

[Taun]

Thanks for keeping this thread alive and updated Waspie...

Great read...

[ninjadude]

Matabei is kind of cool as well with dark ejecta or "flows"? A lead volcano? If I remember right, lead flows on Mercury. Or it could just be dark minerals ejected.

[Waspie_Dwarf]

A First Look at Terrain Near Mercury's North Pole

Release Date: March 30, 2011

Date acquired: March 29, 2011

Image Mission Elapsed Time (MET): 209895911

Image ID: 65416

Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)

WAC filter: 7 (748 nanometers wavelength)

Center Latitude: 81.2°

Center Longitude: 72.3° E

Resolution: 166 meters/pixel (0.10 miles/pixel)

Scale: The bottom of this image is about 84 kilometers (52 miles) across

Of Interest: This WAC image showing a never-before-imaged area of Mercury’s surface was taken from an altitude of ~450 km (280 miles) above the planet during the spacecraft’s first orbit with the camera in operation. The area is covered in secondary craters made by an impact outside of the field of view. Some of the secondary craters are oriented in chain-like formations.

This image was taken during MESSENGER’s closest approach to the sunlit portion of the surface during this orbit, just before crossing over the terminator. The oblique illumination by the Sun causes the long shadows and accentuates topography. The highly elliptical orbit of MESSENGER brings the spacecraft down to a periapsis (MESSENGER’s closest approach to Mercury) altitude of ~200 km (125 miles) and out to an apoapsis (MESSENGER’s farthest distance from Mercury) altitude of ~15,000 km (9300 miles).

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

[Waspie_Dwarf]

MESSENGER’s Wide-Angle Camera

Release Date: March 30, 2011

Date acquired: March 29, 2011

Image Mission Elapsed Time (MET): 0209894354, 0209894356, 0209894362,

Image ID: 65195, 65196, 65200

Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)

WAC filter: 6,7,9 (433, 749, 996 nanometers wavelength)

Center Latitude: 18.1°

Center Longitude: 18.3° E

Resolution: 980 meters/pixel

Scale: Image width is approximately 510 km

Of Interest: The wide-angle camera (WAC) is not a typical color camera. It can image in 11 colors, ranging from 430 to 1020 nm wavelength (visible through near-infrared). It does this with a filter wheel: the 11 narrow-band filters (plus one clear filter) are mounted onto a wheel that can be rotated to allow the camera to capture an image through each filter. In this image the 1000 nm, 750 nm, and 430 nm filters are displayed in red, green, and blue, respectively. Several craters appear to have excavated compositionally distinct low-reflectance (brown-blue in this color scheme) material, and the bright rays of Hokusai crater to the north cross the image. During MESSENGER’s orbital operations, we will typically use just eight of the WAC's filters. This decision was made to reduce the amount of data that must be stored on the spacecraft’s solid-state recorder before the information can be downlinked. It’s also quicker than cycling through all 11 filters – the spacecraft is moving rapidly over the surface, and there isn't much time to image the same spot on the surface 11 times over before moving to the next area of interest. The sets of color images will help us learn about the variation in composition from place to place on the planet. For example, some minerals such as olivine and pyroxene often absorb more light at longer wavelengths than at shorter ones, so we’ll be looking for their signatures in the reflectance spectra derived from each eight-color set. WAC images will be used in coordination with the Mercury Atmospheric and Surface Composition Spectrometer (MASCS), a hyperspectral instrument that provides reflectance information at many more wavelengths, but only for one spot on the surface at a time.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

[Waspie_Dwarf]

From Orbit, Looking toward Mercury's Horizon

Release Date: March 30, 2011

Date acquired: March 29, 2011

Image Mission Elapsed Time (MET): 209892080

Image ID: 65134

Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)

WAC filter: 7 (748 nanometers wavelength)

Center Latitude: 5.2°

Center Longitude: 341° E

Scale: The right side of this image is about 1,200 kilometers (750 miles) in extent

Of Interest: MESSENGER acquired this image of Mercury's horizon as the spacecraft was moving northward along the first orbit during which MDIS was turned on. Bright rays from Hokusai can be seen running north to south in the image. MDIS frequently acquired images that contained Mercury's horizon during the mission's three Mercury flybys. (Visit these links to see examples of horizon images from Mercury flyby 1, Mercury flyby 2, and Mercury flyby 3.) However, now that MESSENGER is in orbit about Mercury, views of Mercury's horizon in the images will be much less common. The field of view for MDIS will generally be filled with Mercury's surface as the instrument maps out the planet's geology in high resolution, stereo, and color. Occasionally, in order to obtain images of a certain portion of Mercury's surface, the horizon will also be visible.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

[Waspie_Dwarf]

Smooth Plains in Mercury's North

Release Date: March 30, 2011

Date acquired: March 29, 2011

Image Mission Elapsed Time (MET): 209895977

Image ID: 65419

Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)

WAC filter: 7 (748 nanometers wavelength)

Center Latitude: 81.3°

Center Longitude: 44.4° E

Resolution: 200 meters/pixel (0.12 miles/pixel)

Scale: The bottom of this image is about 100 kilometers (60 miles) across

Of Interest: As the MESSENGER spacecraft passed low over Mercury's north polar region, MDIS used its pivot to capture this image, showing terrain that had not been previously seen by spacecraft. The newly imaged surface is located in Mercury's north polar region, to the north of the bright, rayed crater Hokusai. Looking from the bottom of the image toward the top is looking southward, just as MDIS was doing when this image was acquired.

This newly seen terrain shows craters with long shadows, as expected at this high northern latitude. Understanding the interiors of the craters in Mercury's polar regions and any ices they may contain is one of the main science goals of the MESSENGER mission. The long shadows also accentuate the topography of the surface, which includes a number of ridges that resemble those seen on the expansive smooth plains imaged during Mercury flyby 3.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

[Waspie_Dwarf]

Simply Beautiful

Release Date: March 30, 2011

Date acquired: March 29, 2011

Image Mission Elapsed Time (MET): 209894125

Image ID: 65182

Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)

Center Latitude: 11.8.°

Center Longitude: 13.9.° E

Resolution: 160 meters/pixel

Scale: The bright crater is about 6.4 km (4 miles) in diameter.

Of Interest: The crater near the bottom of this image is a beautiful example of a relatively small, simple, fresh impact feature on Mercury. It illustrates the textbook characteristics of a crater in its size range. The crater is nearly bowl-shaped, with just a small flat area in the center of its floor. The walls and rim are sharp and do not appear to have suffered the collapse and terracing that modify larger craters. The bright ejecta and rays are symmetrically distributed around the crater, indicating that the body that struck Mercury to form the crater approached on a path that was not highly inclined from the vertical.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

[Waspie_Dwarf]

First NAC Image Obtained in Mercury Orbit

Release Date: March 30, 2011

Date acquired: March 29, 2011

Image Mission Elapsed Time (MET): 209878668

Image ID: 65064

Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)

Center Latitude: -53°

Center Longitude: 13° E

Resolution: 380 meters/pixel

Scale: This image is 390 kilometers (240 miles) across

Of Interest: This is the first image of Mercury taken from orbit with MESSENGER’s Narrow Angle Camera (NAC). MESSENGER’s camera system, the Mercury Dual Imaging System (MDIS), has two cameras: the Narrow Angle Camera and the Wide Angle Camera (WAC). Comparison of this image with MESSENGER’s first WAC image of the same region shows the substantial difference between the fields of view of the two cameras. At 1.5°, the field of view of the NAC is seven times smaller than the 10.5° field of view of the WAC.

This image was taken using MDIS’s pivot. MDIS is mounted on a pivoting platform and is the only instrument in MESSENGER’s payload capable of movement independent of the spacecraft. The other instruments are fixed in place, and most point down the spacecraft’s boresight at all times, relying solely on the guidance and control system for pointing. The 90° range of motion of the pivot gives MDIS a much-needed extra degree of freedom, allowing MDIS to image the planet’s surface at times when spacecraft geometry would normally prevent it from doing so. The pivot also gives MDIS additional imaging opportunities by allowing it to view more of the surface than that at which the boresight-aligned instruments are pointed at any given time.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

[Waspie_Dwarf]

First Color Image of Mercury from Orbit

Release Date: March 30, 2011

Date acquired: March 29, 2011

Image Mission Elapsed Time (MET): 0209877871, 0209877891, 0209877875

Image IDs: 65056, 65057, 65061

Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)

WAC filters: 6,7,9 (433, 749, 996 nanometers wavelength)

Center Latitude: -53.3°

Center Longitude: 13.0° E

Resolution: 2.7 kilometers/pixel

Scale: Debussy has a diameter of 80 kilometers (50 miles)

Of Interest: The first image acquired by MESSENGER from orbit around Mercury was actually part of an eight-image sequence, for which images were acquired through eight of the WAC’s eleven filters. Here we see a color version of that first imaged terrain; in this view the images obtained through the filters with central wavelengths of 1000 nm, 750 nm, and 430 nm are displayed in red, green, and blue, respectively. One of MESSENGER’s measurement objectives is to create an eight-color global base map at a resolution of 1 km/pixel (0.6 miles/pixel) to help understand the variations of composition across Mercury’s surface.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

[Waspie_Dwarf]

Revisiting Boccaccio

Release Date: March 31, 2011

Date acquired: March 30, 2011

Image Mission Elapsed Time (MET): 209950645

Image ID: 67380

Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)

Center Latitude: -78.9°

Center Longitude: 199.4° E

Resolution: 290 meters/pixel (0.18 miles)

Scale: Boccaccio crater has a diameter of 142 km (88 miles)

Of Interest: Giovanni Boccaccio was a 14th century Italian poet and novelist. The 142-km-diameter crater at the top of this MESSENGER NAC image was named for Boccaccio after Mariner 10 imaged the region during its second Mercury flyby in 1974. This MESSENGER NAC image reveals the crater under different lighting conditions than at the time of the Mariner 10 flyby. Boccaccio has a prominent central peak, which was formed by uplift from beneath the surficial material at the point of impact.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

Edited March 31, 2011 by Waspie_Dwarf
corrected title.

[DONTEATUS]

Great work passing all this on to us Waspie !

Makes one really appreciate our atmosphere ! We would most likely Look a great deal like that !

[Waspie_Dwarf]

Makes one really appreciate our atmosphere ! We would most likely Look a great deal like that !

It's about more than having an atmosphere; just look at Mars.

Although our thick atmosphere protects us from smaller impacts it has virtually no effect on the larger objects. Many of the craters you see on Mercury, the Moon, Jupiter & Saturn's satellites and so on are very ancient, many dating back to a period known as the Late Heavy Bombardment, approximately 4.1 to 3.8 billion years ago. During that period the Earth too would have been covered in huge impact craters. The difference is that on Earth we have oceans, rivers, rain, glaciers, volcanism and plate tectonics, all of which effectively resurface the planet and remove the old impact craters.

[Waspie_Dwarf]

Debussy Makes a Good Impression

Release Date: March 31, 2011

Date acquired: March 29, 2011

Image Mission Elapsed Time (MET): 209886978

Image ID: 65083

Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)

WAC filter: 9 (996 nanometers wavelength)

Center Latitude: -29.7°

Center Longitude: 14.5° E

Resolution: 2 kilometers/pixel (1.2 miles/pixel)

Scale: Debussy has a diameter of 80 kilometers (50 miles)

Of Interest:This image shows Debussy crater, named for the impressionist-era French composer Claude Debussy. The impact crater's rim is 80 km in diameter, and the bright crater rays extend for hundreds of kilometers. The object that impacted the surface to form this crater was probably between 4 and 8 km in diameter.

This image was taken with MESSENGER’s Wide Angle Camera (WAC) using the 997-nm filter, one of the 12 filters available for use with the WAC. The WAC is a refracting telescope with a focal length of 78 mm, a field of view of 10.5°, and a collecting area (entrance pupil aperture) of 48 mm2. The detector located on the focal plane is a 1024 × 1024 pixel (1 megapixel) CCD. The filters, which reside on a rotating wheel, range in wavelength from 430 nm to 1040 nm (visible through near-infrared) and include a broadband filter for optical navigation imaging of stars.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

Edited April 1, 2011 by Waspie_Dwarf
corrected source link.

[Waspie_Dwarf]

Dark Material on Mercury

Release Date: March 31, 2011

Date acquired: March 29, 2011

Image Mission Elapsed Time (MET): 209895047

Image ID: 65239

Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)

WAC filter: 7 (748 nanometers wavelength)

Center Latitude: 40.5°

Center Longitude: 27.4° E

Resolution: 290 meters/pixel (0.18 miles/pixel)

Scale: This image is approximately 300 kilometers (190 miles) across

Of Interest: As the MESSENGER spacecraft moved northward during the first orbit for which images were acquired, the WAC captured this image. The bright rays from Hokusai can be seen extending across this image, but also clearly visible near the center of this image is a small patch of material that is considerably darker than the surrounding terrain. Other locations with dark material have been spotted across Mercury's surface, including the floor of Hemingway crater, as a halo surrounding Derain, as rays from Matabei, and near some craters in Caloris basin. What is this dark material? Likely it is due to a dark type of rock on Mercury's surface, but there is not currently enough information to identify the type of rock. However, with MESSENGER now in orbit, that situation will soon change, as MESSENGER's orbital science campaign will provide unprecedented chemical information about the rock types on Mercury's surface.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

[Waspie_Dwarf]

Mercury's Colorful Limb

Release Date: March 31, 2011

Date acquired: March 29, 2011

Image Mission Elapsed Time (MET): 209890193, 209890197, 209890213

Image ID: 65109, 65110, 65114

Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)

WAC filter: 6,7,9 (433, 749, 996 nanometers wavelength)

Center Latitude: 3.1°

Center Longitude: 352.3° E

Resolution: 1.5 kilometers/pixel

Scale: The radius of Mercury is 2440 km

Of Interest: As in this monochrome view of Mercury, the bright rays of Hokusai crater can be seen crossing the surface from north to south. This color image, with the central wavelengths of 1000 nm, 750 nm, and 430 nm displayed in red, green, and blue, respectively, also highlights some of the subtle color variations observed on Mercury. Spectral variations can be due to differences in particle size, duration of time exposed on surface, or composition. The MESSENGER team is working hard to unravel the complicated story contained in these beautiful color images.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

[Waspie_Dwarf]

Mercury's Colorful Limb

Release Date: April 1, 2011

Date acquired: March 31, 2011

Image Mission Elapsed Time (MET): 210025195

Image ID: 71248

Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)

WAC filter: 7 (748 nanometers wavelength)

Center Latitude: 32.2°

Center Longitude: 16.3° E

Resolution: 720 meters/pixel (0.45 miles/pixel)

Scale: Hodgkins has a diameter of 19 kilometers (12 miles)

Of Interest: The rayed crater near the bottom of this image is Hodgkins, named in July 2009 in honor of the New Zealand painter Frances Hodgkins (1869-1947). In this image, north is approximately toward the upper right corner. Hodgkins has an asymmetric pattern of rays, which provides information about the impact event that formed the crater. Hodgkins' asymmetric rays were formed when an object, traveling in either a northeastern or southwestern direction, struck Mercury at a low angle to the surface. Compare the rays of Hodgkins to the rays of Qi Baishi and Hovnatanian, and read more about low-angle impacts. Visit this image of Bek to learn more about how rays form and how they fade with time.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

[Waspie_Dwarf]

Two Kinds of Small Craters

Release Date: April 1, 2011

Date acquired: March 30, 2011

Image Mission Elapsed Time (MET): 209982350

Image ID: 69294

Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)

WAC filter: 7 (748 nanometers wavelength)

Center Latitude: 56.5°

Center Longitude: 23.5° E

Resolution: 187 meters/pixel

Scale: The scene is about 191 kilometers across (119 miles).

Of Interest: This image covers an area of ridged plains to the east of the rim of Hokusai crater on Mercury. The crater's bright rays and ejecta cross the location. The image has higher spatial resolution and a more favorable viewing angle than the coverage of Hokusai from MESSENGER's second flyby and is just one of many images of this impact crater and its environs being collected as part of commissioning activities during MESSENGER's first orbits around Mercury. Here we see chains of small secondary craters that were formed by chunks of debris thrown out of Hokusai during its formation, surrounded by more diffuse high-reflectance rays. A very small, very bright, very fresh (young) primary impact crater and its ejecta blanket light up the top-middle part of the image. North is approximately to the top in this image.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

[Waspie_Dwarf]

WAC versus NAC

Release Date: April 1, 2011

Date acquired: March 30, 2011

Image Mission Elapsed Time (MET): 09893893, 209894056

Image ID: 65176, 65181

Instrument: Wide Angle Camera (WAC) and Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)

WAC filter: 7 (748 nanometers)

Center Latitude: 6.64° (WAC), 10.01° (NAC)

Center Longitude: 8.75° E (WAC), 12.25° E (NAC)

Resolution: 1278 meters/pixel (WAC), 166 meters/pixel (NAC)

Scale: The WAC image is about 650 meters (404 miles) across. The NAC image is about 84 meters (52 miles) across.

Of Interest:

This pair of images illustrates the differences between the footprints of the WAC and the NAC, the two cameras that make up the Mercury Dual Imaging System (MDIS). The image on the left is a WAC image that includes several bright craters. Their bright ejecta patterns indicate that the craters are relatively young. The image on the right is a NAC image taken within the footprint of the WAC image, revealing a complex crater with a central peak (marked by the X). The WAC field of view is approximately seven times wider than that of the NAC. The WAC can image the planet through 11 different color filters. The NAC provides the highest-resolution views of Mercury’s surface.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

[Waspie_Dwarf]

I don't usually comment on these NASA releases when I post them, but I'm making an exception in this case. Before looking at the release below please consider carefully the date it was released and the date on which the MESSENGER team clain it was acquired... April 1^st 2011.

Enough said.

Waspie_Dwarf

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Encounter with the Ancient Mariner

Release Date: April 1, 2011

Date acquired: April 1, 2011

Image Mission Elapsed Time (MET): 209890197

Image ID: 65110

Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)

WAC filter: 7 (749 nanometers wavelength)

Center Latitude: 3.1°

Center Longitude: 352.3° E

Resolution: 1.5 kilometers/pixel

Scale: The radius of Mercury is 2440 km

Of Interest: MESSENGER captured this image while taking one of its first pictures from orbit around the planet Mercury. The frame shown is one of several images obtained of the same view through the different color filters of the Mercury Dual Imaging system (MDIS) Wide Angle Camera (WAC).

The first reaction of some on the MESSENGER team was that the feature to the left of Mercury’s limb must be an imaging artifact. “It’s the effect of solar neutrinos on the WAC’s CCD,” pronounced Project Scientist Mack Knott. The imaging team was skeptical of this explanation, however, and all Knott could add was “I could explain it to you, but you’d have to understand Feynman diagrams.”

The imaging team brought the anomalous image to the attention of Mission Systems Engineer E. Finn Again, who immediately called an emergency gathering of the Collision Avoidance Review Board. Fortunately, the unusual object in the image did not appear to be in the immediate path of MESSENGER’s next few orbits, but the fact that earlier and subsequent images of the same scene did not include the object prevented a determination of its trajectory.

One of MESSENGER’s Science Team members, Prof. S. T. Rom, recognized the object immediately as Mariner 10, the only spacecraft before MESSENGER to have visited Mercury. Launched in 1973, Mariner 10 flew by Mercury three times in 1974 and 1975 before communication with the probe was lost. Prof. Rom is the only member of the MESSENGER team to have served on the science team of Mariner 10 as well.

The Science Operations Center was filled at the time with MESSENGER team members, and everyone proceeded at once to theorize on why Mariner 10 might appear in an MDIS image of Mercury.

Professor Rom suggested that Mariner 10 may have remained in place as of the time of its last signal:

“Day after day, day after day,

We stuck, nor breath nor motion;

As idle as a painted ship

Upon a painted ocean.”

The dead albatross hanging from Rom’s neck, however, reduced the effectiveness of his argument.

Mission design lead Mick Adams quickly calculated that Mariner 10 should not be encountering Mercury on this date. “Mariner 10 and Mercury were in a resonant state that brought the spacecraft by the planet once every two Mercury years. By my calculation, this appearance is 23 days early.”

Guidance and control lead E. C. Shaughn offered that the effect of solar radiation should have substantially altered Mariner 10’s orbit over the past 36 years as a result of solar sailing:

“With throats unslaked, with black lips baked,

We could nor laugh nor wail;

Through utter drought all dumb we stood!

I bit my arm, I sucked the blood,

And cried, A sail! a sail!”

Propulsion lead Brecht Engel added that some residual propellant after Mariner 10’s last propulsive maneuver may have outgassed, and that multiple outgassing events may also have contributed to trajectory changes:

“A speck, a mist, a shape, I wist!

And still it neared and neared:

As if it dodged a water-sprite,

It plunged and tacked and veered.”

MESSENGER’s navigation team members, all of whom are named Williams, plugged these suggestions into their codes. Minutes later they were able to announce to all assembled that Mariner 10 appeared to be in a new resonant state, one synchronous with Earth’s period. The ancient spacecraft is locked into an orbit that swings it by Mercury once every Earth year, on April 1st.

As MESSENGER passed into eclipse behind Mercury, Prof. Rom had the last word:

“The sun's rim dips; the stars rush out:

At one stride comes the dark;

With far-heard whisper o'er the sea,

Off shot the spectre-bark.”

Source: JHUAPL - MESSENGER - Gallery

[Waspie_Dwarf]

We've Got the NAC of It

Release Date: April 1, 2011

Date acquired: March 29, 2011

Image Mission Elapsed Time (MET): 209889250

Image ID: 65107

Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)

Center Latitude: 1.7°

Center Longitude: 354.3° E

Resolution: 246 meters/pixel

Scale: This image is 390 kilometers (240 miles) across

Of Interest: This image of a number of unnamed craters was taken with MESSENGER’s Narrow Angle Camera (NAC), one of the two cameras that make up the Mercury Dual Imaging System (MDIS). The NAC is an off-axis reflector telescope with a focal length of 550 mm, a field of view of 1.5°, and a collecting area of 462 mm2. The detector located on the focal plane is a 1024 × 1024 pixel (1 megapixel) CCD. The NAC takes monochromatic images using a single medium-band filter, unlike the Wide Angle Camera, or WAC, which can view the planet through one of 11 different spectral filters or a broadband filter.

This image was taken using MDIS’s pivot. MDIS is mounted on a pivoting platform and is the only instrument in MESSENGER’s payload capable of movement independent of the spacecraft. The other instruments are fixed in place, and most point down the spacecraft’s boresight at all times, relying solely on the guidance and control system for pointing. The 90° range of motion of the pivot gives MDIS a much-needed extra degree of freedom, allowing MDIS to image the planet’s surface at times when spacecraft geometry would normally prevent it from doing so. The pivot also gives MDIS additional imaging opportunities by allowing it to view more of the surface than just that at which the boresight-aligned instruments are pointed at any given time.

On March 17, 2011 (March 18, 2011, UTC), MESSENGER became the first spacecraft to orbit the planet Mercury. The mission is currently in its commissioning phase, during which spacecraft and instrument performance are verified through a series of specially designed checkout activities. In the course of the one-year primary mission, the spacecraft's seven scientific instruments and radio science investigation will unravel the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the science questions that the MESSENGER mission has set out to answer.

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

Source: JHUAPL - MESSENGER - Gallery

Edited April 3, 2011 by Waspie_Dwarf
added link.