Updates Dawn Mission News

[Turbinator]

"The team does not plan to post raw images online as other NASA missions have done. Instead, there will be just one picture released daily."


Why are they going the way of ESA and JAXA Why?

 

[elephantium]

Oi, that's frustrating. Personally, I find the photos we get from missions like Dawn to be tremendously inspiring.

To say nothing of wanting textures for Orbiter missions...

 

[orb]

NASA / NASA JPL:
NASA's Asteroid Photographer Beams Back Science Data

August 11, 2011

The Dawn spacecraft has completed a graceful spiral into the first of four planned science orbits during the spacecraft's yearlong visit to Vesta. The spacecraft started taking detailed observations on Aug. 11 at 9:13 a.m. PDT (12:13 a.m. EDT), which marks the official start of the first science-collecting orbit phase at Vesta, also known as the survey orbit.

Click on image for details​

This anaglyph image of Vesta's equator was put together from two clear filter images, taken on July 24, 2011 by the framing camera instrument aboard NASA's Dawn spacecraft.​

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​

Survey orbit is the initial and highest orbit, at roughly 1700 miles (2700 kilometers) above the surface, which will provide an overview or "big picture" perspective of the giant asteroid.

The primary objective of survey orbit is to image the surface with near-global coverage in visible and infrared wavelengths with the mapping spectrometer, also known as VIR. Dawn also will be using its framing camera to collect image mosaics that complement the VIR spectral data to produce geologic and compositional maps of Vesta's surface. Ultrasensitive measurements of the spacecraft's motion using radio signals will allow improved understanding of the giant asteroid's gravity field. Dawn's gamma ray and neutron detector will continue to collect background data.

The survey phase is planned to last 20 days. Each orbit takes almost three days, which will provide the spacecraft seven trips around Vesta. After survey orbit, Dawn will resume thrusting, taking about a month to spiral down gently to its next science orbit for an even closer view. That orbit, known as High Altitude Mapping Orbit, or HAMO, begins in late September. Dawn will spend about a month in HAMO, circling around Vesta in half a day, rather than three. Dawn will orbit more than 60 times during HAMO, allowing the camera to fully map the illuminated portion of Vesta at even higher resolution, and enable the science team to generate stereo images.

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SPACE.com: Dawn Spacecraft Begins Science Mission at Asteroid Vesta

 

[orb]

NASA / NASA JPL:
NASA's Dawn Collects a Bounty of Beauty from Vesta

September 16, 2011

PASADENA, Calif. - A new video from NASA's Dawn spacecraft takes us on a flyover journey above the surface of the giant asteroid Vesta.

{colsp=2}Asteroid Vesta as seen by NASA’s Dawn spacecraft.

› Download video​

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› False-color video​

The data obtained by Dawn's framing camera, used to produce the visualizations, will help scientists determine the processes that formed Vesta's striking features. It will also help Dawn mission fans all over the world visualize this mysterious world, which is the second most massive object in the main asteroid belt.

The video, which shows Vesta as seen from Dawn's perspective, can be viewed at: http://www.jpl.nasa.gov/video/index.cfm?id=1020.

You'll notice in the video that Vesta is not entirely lit up. There is no light in the high northern latitudes because, like Earth, Vesta has seasons. Currently it is northern winter on Vesta, and the northern polar region is in perpetual darkness. When we view Vesta's rotation from above the south pole, half is in darkness simply because half of Vesta is in daylight and half is in the darkness of night.

Another distinct feature seen in the video is a massive circular structure in the south pole region. Scientists were particularly eager to see this area close-up, since NASA's Hubble Space Telescope first detected it years ago. The circular structure, or depression, is several hundreds of miles, or kilometers, wide, with cliffs that are also several miles high. One impressive mountain in the center of the depression rises approximately 9 miles (15 kilometers) above the base of this depression, making it one of the highest elevations on all known bodies with solid surfaces in the solar system.

The collection of images, obtained when Dawn was about 1,700 miles (2,700 kilometers) above Vesta's surface, was used to determine its rotational axis and a system of latitude and longitude coordinates. One of the first tasks tackled by the Dawn science team was to determine the precise orientation of Vesta's rotation axis relative to the celestial sphere.

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Viewing the South Pole of VestaThis image obtained by the framing camera on NASA's Dawn spacecraft shows the south pole of the giant asteroid Vesta.​

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​

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High Cliffs at Vesta's South PoleThe south pole of the giant asteroid Vesta reveals cliffs that are several miles or kilometers high, deep grooves, and craters.​

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​

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False-Color Image Shows Proof of an ImpactThis false-color image obtained by NASA's Dawn spacecraft shows a crater on the giant asteroid Vesta.​

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​

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Map of Vesta's Equatorial Latitudes and Southern HemisphereThis is the first global map of the giant asteroid Vesta composed from images recorded by the framing camera aboard NASA's Dawn spacecraft.​

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​

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Map of Vesta's South PoleThis image mosaic of Vesta's south pole is generated from dozens of individual images obtained by the framing camera aboard NASA's Dawn spacecraft.​

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​

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Vesta's Surface in 3D: A Big Mountain at the Asteroid's South PoleWhen Dawn sent the first images of the giant asteroid Vesta to the ground, scientists were fascinated by this surface feature at the south pole.​

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​

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Vesta's Surface in 3D: Details of Wave-Like Terrain in the South PoleIn this image, obtained by NASA's Dawn spacecraft, topography in the area surrounding Vesta's south pole area shows impact craters, ridges and grooves.​

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​

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Vesta's Surface in 3D: An Ancient, Cratered SurfaceIn this image of the giant asteroid Vesta obtained by NASA's Dawn spacecraft, numerous impact craters illustrate the asteroid's violent youth.​

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​

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A False-Color Topography of Vesta's South PoleThis false-color map of the giant asteroid Vesta was created from stereo images obtained by the framing camera aboard NASA's Dawn spacecraft.​

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​

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Impressive Mountain Tops on VestaIn this image of the south pole region of the asteroid Vesta, a mountain is rising approximately 9 miles (15 kilometers) above the floor of a crater.​

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​

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Claudia: A Tiny Crater Chosen to Define Vesta's Prime MeridianThe image from Dawn shows Claudia (arrow), a tiny crater of about 1500 yards (500 meters) in diameter through which by definition Vesta's prime meridian runs from the asteroid's north pole to its south pole.​

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​

The zero-longitude, or prime meridian, of Vesta was defined by the science team using a tiny crater about 1,640 feet (500 meters) in diameter, which they named "Claudia," after a Roman woman during the second century B.C. Dawn's craters will be named after the vestal virgins-the priestesses of the goddess Vesta, and famous Roman women, while other features will be named for festivals and towns of that era.

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[orb]

A couple of Dawn videos from Vesta:

 

[orb]

Universe Today: Rhea Silvia – Super Mysterious South Pole Basin at Vesta is Named after Romulus and Remus Roman Mother

 

[orb]

Universe Today: Dramatic 3 D Imagery Showcases Vesta’s Pockmarked, Mountainous and Groovy Terrain:

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In a few days, Dawn begins snapping images from a much lower altitude at the HAMO mapping orbit of ca. 685 km vs the initial survey orbit of ca, 2700 km. where most of these images were taken.

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Red-cyan anaglyph images from Vesta:

 

[IronRain]

Jet Propulsion Laboratory: NASA's Dawn Spacecraft Begins New Vesta Mapping Orbit

PASADENA, Calif. -- NASA's Dawn spacecraft has completed a gentle spiral into its new science orbit for an even closer view of the giant asteroid Vesta. Dawn began sending science data on Sept. 29 from this new orbit, known as the high altitude mapping orbit (HAMO).

In this orbit, the average distance from the spacecraft to the Vesta surface is 420 miles (680 kilometers), which is four times closer than the previous survey orbit. The spacecraft will operate in the same basic manner as it did in the survey orbit. When Dawn is over Vesta's dayside, it will point its science instruments to the giant asteroid and acquire data, and when the spacecraft flies over the nightside, it will beam that data back to Earth.

Perhaps the most notable difference in the new orbit is the frequency with which Dawn circles Vesta. In survey orbit, it took Dawn three days to make its way around the asteroid. Now in HAMO, the spacecraft completes the same task in a little over 12 hours. HAMO is scheduled to last about 30 Earth days, during which Dawn will circle Vesta more than 60 times. For about 10 of those 30 days, Dawn will peer straight down at the exotic landscape below it during the dayside passages. For about 20 days, the spacecraft will view the surface at multiple angles.

Scientists will combine the pictures to create topographic maps, revealing the heights of mountains, the depths of craters and the slopes of plains. This will help scientists understand the geological processes that shaped Vesta.

HAMO, the most complex and intensive science campaign at Vesta, has three primary goals: to map Vesta's illuminated surface in color, provide stereo data, and acquire visible and infrared mapping spectrometer data. In addition, it will allow improved measurements of Vesta's gravity.

Dawn launched in September 2007 and arrived at Vesta in July 2011. Since beginning its first survey orbit in August, Dawn has been extensively imaging this intriguing world, sending back a bounty of images and other data. NASA-funded scientists and European scientists on the Dawn mission team will present a wealth of new findings at the joint meeting of the American Astronomical Society's Division for Planetary Sciences and the European Planetary Science Congress next week at La Cite Internationale des Congres Nantes Metropole, Nantes, France.

These findings about the giant asteroid Vesta will include information about the new coordinate system and official names of Vesta's prominent features.

A Dawn mission news conference will be held Monday, Oct. 3, 2011 at 12:15 p.m. CEST (3:15 a.m. PDT/6:15 a.m. EDT). The Division for Planetary Sciences will provide live Web streaming of this news conference, at:
http://meetings.copernicus.org/epsc-dps2011/webstreaming/monday.html

"The team has been in awe of what they have seen on the surface of Vesta," said Christopher Russell, Dawn principal investigator, at UCLA. "We are sharing those discoveries with the greater scientific community and with the public."

Following a year at Vesta, the spacecraft will depart in July 2012 for Ceres, where it will arrive in 2015. Dawn's mission to Vesta and Ceres is managed by the Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Science Mission Directorate in Washington. JPL is a division of the California Institute of Technology in Pasadena. Dawn is a project of the directorate's Discovery Program, managed by NASA's Marshall Space Flight Center in Huntsville, Ala. UCLA is responsible for overall Dawn mission science. Orbital Sciences Corp. in Dulles, Va., designed and built the spacecraft. The German Aerospace Center, the Max Planck Institute for Solar System Research, the Italian Space Agency and the Italian National Astrophysical Institute are international partners on the mission team.

 

[orb]

SPACE.com: Giant Asteroid Vesta Has Mountain Taller Than Anything on Earth:

A NASA spacecraft orbiting the asteroid Vesta is revealing new details about the huge space rock's surface, including a massive mountain that rises taller than Mt. Everest on Earth.

NASA's Dawn probe has been circling Vesta since mid-July, when it arrived in the asteroid belt that orbits the sun between Mars and Jupiter. So far, Dawn has beamed back surprising views of Vesta that revealed an enormous mountain in the asteroid's southern hemisphere and show that its crater surface is incredibly diverse place.

"We are learning many amazing things about Vesta, which we call the smallest terrestrial planet," Chris Russell, principal investigator of the Dawn mission, said in a statement. "Like Earth, Mars, Venus and Mercury, Vesta has ancient basaltic lava flows on the surface and a large iron core … The south polar mountain is larger than the big island of Hawaii, the largest mountain on Earth, as measured from the ocean floor. It is almost as high as the highest mountain in the solar system, the shield volcano Olympus Mons on Mars."

Vesta's giant southern mountain is nearly as tall as Olympus Mons, the largest mountain (and volcano) in the solar system, which soars about 15 miles (24 kilometers) above the surface. On Earth, the largest terrestrial volcano is Mauna Loa in Hawaii, which rises up 6 miles (9 km) high, including the portion of the volcano that extends underwater to the sea floor. Mount Everest, the tallest mountain above sea level on Earth, is a paltry 5.5 miles (8.85 km) tall.

Dawn also revealed that Vesta's surface appears to be much rougher than most asteroids in the main asteroid belt, which is a vast region full of space rocks between the orbits of Mars and Jupiter.

Additionally, preliminary estimates of crater age dates on Vesta suggest that regions in the southern hemisphere are far younger than in the north — with some areas in the southern hemisphere only about 1 to 2 billion years old.

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[orb]

NASA / NASA JPL:
New View of Vesta Mountain From NASA's Dawn Mission

October 10, 2011

A new image from NASA's Dawn spacecraft shows a mountain three times as high as Mt. Everest, amidst the topography in the south polar region of the giant asteroid Vesta.

The peak of Vesta's south pole mountain, seen in the center of the image, rises about 13 miles (22 kilometers) above the average height of the surrounding terrain. Another impressive structure is a large scarp, a cliff with a steep slope, on the right side of this image. The scarp bounds part of the south polar depression, and the Dawn team's scientists believe features around its base are probably the result of landslides.

Click on image for details​

This image of the asteroid Vesta, calculated from a shape model, shows a tilted view of the topography of the south polar region.​

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/PSI​

The image is online at: http://www.nasa.gov/mission_pages/dawn/multimedia/pia14869.html. It was created from a shape model of Vesta, and shows an oblique perspective view of the topography of the south polar region. The image resolution is about 300 meters per pixel, and the vertical scale is 1.5 times that of the horizontal scale.

Dawn entered orbit around Vesta in July. Members of the mission team will discuss what the spacecraft has seen so far during a news conference at the Annual Meeting of the Geological Society of America in Minneapolis. Among other things, they'll share their hypotheses on the origins of Vesta's curious craters.

The meeting, at the Minneapolis Convention Center, runs from Oct. 9 to 12, with the Dawn news conference scheduled for Wednesday, Oct. 12, at 10 a.m. PDT (noon CDT) [17:00 UTC].

The event will air live on the Geological Society of America webcast page at:

• http://hosted.mediasite.com/mediasite/Viewer/?peid=e8adbee5a37e455fbe199b29129e3b7c1d.

Media representatives not able to attend the meeting may participate by registering at:

• http://rock.geosociety.org/forms/11_pressConf.asp.

More information about the webcast is at:

• http://www.geosociety.org/news/pr/11-63.html.

The event will also be carried live, with a moderated chat, at: http://www.ustream.tv/nasajpl2.

The news conference panelists are:

• Carol Raymond, Dawn deputy principal investigator, NASA's Jet Propulsion Laboratory, Pasadena, Calif.
• Paul Schenk, Dawn participating scientist, Lunar and Planetary Institute, Houston
• Debra Buczkowski, Dawn participating scientist, Applied Physics Laboratory, Johns Hopkins University, Laurel, Md.
• Federico Tosi, Dawn Visible and Infrared Spectrometer team member, Italian Space Agency, Rome

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[orb]

NASA / NASA JPL:
NASA's Dawn Science Team Presents Early Science Results

October 12, 2011

Scientists with NASA's Dawn mission are sharing with other scientists and the public their early information about the southern hemisphere of the giant asteroid Vesta. The findings were presented today at the annual meeting of the Geological Society of America in Minneapolis, Minn.

Dawn, which has been orbiting Vesta since mid-July, has found that the asteroid's southern hemisphere boasts one of the largest mountains in the solar system. Other findings show that Vesta's surface, viewed by Dawn at different wavelengths, has striking diversity in its composition, particularly around craters. Science findings also include an in-depth analysis of a set of equatorial troughs on Vesta and a closer look at the object's intriguing craters. The surface appears to be much rougher than most asteroids in the main asteroid belt. In addition, preliminary dates from a method that uses the number of craters indicate that areas in the southern hemisphere are as young as 1 billion to 2 billion years old, much younger than areas in the north.

Scientists do not yet understand how all the features on Vesta's surface formed, but they did announce today, after analysis of northern and southern troughs, that results are consistent with models of fracture formation due to giant impact.

Click on image for details​

This full view of the giant asteroid Vesta was taken by NASA's Dawn spacecraft, as part of a rotation characterization sequence on July 24, 2011, at a distance of 3,200 miles (5,200 kilometers).​

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​

Since July, the Dawn spacecraft has been spiraling closer and closer to Vesta, moving in to get better and better views of the surface. In early August, the spacecraft reached an orbital altitude of 1,700 miles (2,700 kilometers) and mapped most of the sunlit surface, during survey orbit, with its framing camera and visible and infrared mapping spectrometer.

That phase was completed in late August, and the spacecraft began moving in to what is known as High Altitude Mapping Orbit at about 420 miles (680 kilometers) above Vesta, which it reached on Sept. 29.

An archive of the live news conference is available for viewing at: http://www.ustream.tv/nasajpl2.

The Dawn scientists also shared their findings at the recent European Planetary Science Congress and the Division of Planetary Sciences Joint Meeting 2011 in Nantes, France.

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[orb]

NASA / NASA JPL:
Dawn Soars Over Asteroid Vesta in 3-D

November 30, 2011

PASADENA, Calif. - Glide over the giant asteroid Vesta with NASA's Dawn spacecraft in a new 3-D video. Dawn has been orbiting Vesta since July 15, obtaining high-resolution images of its bumpy, cratered surface and making other scientific measurements.

The new video is available online at: http://www.jpl.nasa.gov/video/index.cfm?id=1041. Best viewed with red-blue glasses, the video incorporates images from Dawn's framing camera from July to August 2011. It was created by Dawn team member Ralf Jaumann of the German Aerospace Center (DLR).

The images were obtained when Dawn was making its approach to Vesta, and while orbiting the giant asteroid in its first science orbit, known as survey orbit, at an altitude of about 1,700 miles (2,700 kilometers). The video begins with a global view of Vesta from the plane of its equator, where a mysterious band of linear ridges and troughs can be seen. The movie cuts to a flyover of young craters in the northern hemisphere, whose peculiar alignment has led some scientists to refer to them as the "snowman." Then this virtual tour of Vesta takes the viewer around a massive mountain at the south pole of Vesta that is about 16 miles (25 kilometers) high, or more than twice the height of Mt. Everest.

"If you want to know what it's like to explore a new world like Vesta, this new video gives everyone a chance to see it for themselves," Jaumann said. "Scientists are poring over these images to learn more about how the craters, hills, grooves and troughs we see were created."

Vesta is the second most massive object in the asteroid belt between Mars and Jupiter. Dawn is currently spiraling down to its low altitude mapping orbit, which will bring the spacecraft to about 130 miles (210 kilometers) above Vesta's surface.

"Dawn's data thus far have revealed the rugged topography and complex textures of the surface of Vesta, as can be seen in this video," said Carol Raymond, deputy principal investigator at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "Soon, we'll add other pieces of the puzzle such as the chemical composition, interior structure, and geologic age to be able to write the history of this remnant protoplanet and its place in the early solar system."

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Universe Today: Vrooming over Vivid Vestan Vistas in Vibrant 3 D – Video

SPACE.com: 3D Video Offers Wild Ride Over Asteroid Vesta

DLR: Asteroid Vesta in 3D - seemingly close enough to touch

 

[orb]

The Planetary Society Blog: Dawn Journal: Riding gravitational currents to LAMO

 

[SiberianTiger]

I have just learned that Vesta, among about 20 of other asteroids, has its own astronomical symbol attributed to it. Actually, there are three alternate symbols, all meaning a flame on an altar:

There's less ambiguity with Ceres:

 

[orb]

NASA / NASA JPL:
New NASA Dawn Visuals Show Vesta's 'Color Palette'

December 05, 2011

Vesta appears in a splendid rainbow-colored palette in new images obtained by NASA's Dawn spacecraft. The colors, assigned by scientists to show different rock or mineral types, reveal Vesta to be a world of many varied, well-separated layers and ingredients. Vesta is unique among asteroids visited by spacecraft to date in having such wide variation, supporting the notion that it is transitional between the terrestrial planets -- like Earth, Mercury, Mars and Venus -- and its asteroid siblings.

Click on image for details​

This image using color data obtained by the framing camera aboard NASA's Dawn spacecraft shows Vesta's southern hemisphere in color, centered on the Rheasilvia formation.​

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​

Related Video:

In images from Dawn's framing camera, the colors reveal differences in the rock composition associated with material ejected by impacts and geologic processes, such as slumping, that have modified the asteroid's surface. Images from the visible and infrared mapping spectrometer reveal that the surface materials contain the iron-bearing mineral pyroxene and are a mixture of rapidly cooled surface rocks and a deeper layer that cooled more slowly. The relative amounts of the different materials mimic the topographic variations derived from stereo camera images, indicating a layered structure that has been excavated by impacts. The rugged surface of Vesta is prone to slumping of debris on steep slopes.

Dawn scientists presented the new images at the American Geophysical Union meeting in San Francisco on Monday, Dec. 5. The panelists included Vishnu Reddy, framing camera team associate, Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany; Eleonora Ammannito, visible and infrared spectrometer team associate, Italian Space Agency, Rome; and David Williams, Dawn participating scientist, Arizona State University, Tucson.

"Vesta's iron core makes it special and more like terrestrial planets than a garden-variety asteroid," said Carol Raymond, Dawn's deputy principal investigator at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "The distinct compositional variation and layering that we see at Vesta appear to derive from internal melting of the body shortly after formation, which separated Vesta into crust, mantle and core."
The presentation also included a new movie, created by David O'Brien of the Planetary Science Institute, Tucson, Ariz., that takes viewers on a spin around a hill on Vesta that appears to be made of a distinctly darker material than the rest of the crust.

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SPACE.com: Asteroid Vesta's 'Rainbow' Ingredients Shine in New Image

Universe Today: Rainbow of Colors Reveal Asteroid Vesta as More Like a Planet

Discovery News: Asteroid Vesta Not An Asteroid After Al

 

[orb]

The Planetary Society Blog: Notes on Dawn at Vesta from the 2011 American Geophysical Union meeting

 

[orb]

NASA / NASA JPL:
NASA's Dawn Spirals Down to Lowest Orbit

December 12, 2011

PASADENA, Calif. - NASA's Dawn spacecraft successfully maneuvered into its closest orbit around the giant asteroid Vesta today, beginning a new phase of science observations. The spacecraft is now circling Vesta at an altitude averaging about 130 miles (210 kilometers) in the phase of the mission known as low altitude mapping orbit.

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Click on images for details​

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This artist's concept shows NASA's Dawn spacecraft orbiting the giant asteroid Vesta.​

Image credit: NASA/JPL-Caltech​

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This image of the giant asteroid Vesta was obtained by NASA's Dawn spacecraft in the evening Nov. 27 PST (early morning Nov. 28, UTC), as it was spiraling down from its high altitude mapping orbit to low altitude mapping orbit.​

Image credit: NASA/JPL-Caltech​

"Dawn has performed some complicated and beautiful choreography in order to reach this lowest orbit," said Marc Rayman, Dawn chief engineer and mission manager based at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "We are in an excellent position to learn much more about the secrets of Vesta's surface and interior."

Launched in 2007, Dawn has been in orbit around Vesta, the second most massive object in the asteroid belt between Mars and Jupiter, since July 15. The team plans to acquire data in the low orbit for at least 10 weeks.

Dawn's framing camera and visible and infrared mapping spectrometer instruments will image portions of the surface at greater resolution than obtained at higher altitudes. But the primary goal of the low orbit is to collect data for the gamma ray and neutron detector (GRaND) and the gravity experiment. GRaND will be looking for the by-products of cosmic rays reflected off Vesta to reveal the identities of many kinds of atoms in the surface of Vesta. The instrument is most effective at this low altitude.

Close proximity to Vesta also enables ultrasensitive measurements of its gravitational field. These measurements will tell scientists about the way masses are arranged in the giant asteroid's interior.

"Dawn's visit to Vesta has been eye-opening so far, showing us troughs and peaks that telescopes only hinted at," said Christopher Russell, Dawn's principal investigator, based at UCLA. "It whets the appetite for a day when human explorers can see the wonders of asteroids for themselves."

After the science collection is complete at the low altitude mapping orbit, Dawn will spiral out and conduct another science campaign at the high altitude mapping orbit altitude (420 miles, or 680 kilometers), when the sun will have risen higher in the northern regions. Dawn plans to leave Vesta in July 2012 and arrive at its second destination, the dwarf planet Ceres, in February 2015.

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Universe Today: Dawn swoops to lowest orbit around Vesta – Unveiling Spectacular Alien World

SPACE.com: NASA Spacecraft Cozies Up to Gigantic Asteroid

 

[orb]

NASA / NASA JPL:
Dawn Obtains First Low Altitude Images of Vesta

December 21, 2011

PASADENA, Calif. - NASA's Dawn spacecraft has sent back the first images of the giant asteroid Vesta from its low-altitude mapping orbit. The images, obtained by the framing camera, show the stippled and lumpy surface in detail never seen before, piquing the curiosity of scientists who are studying Vesta for clues about the solar system's early history.

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Closer and Closer to the Vesta Surface​

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NASA's Dawn spacecraft has spiraled closer and closer to the surface of the giant asteroid Vesta.

Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​

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Contrasting Deposits on Vesta​

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This image, one of the first obtained by NASA's Dawn spacecraft in its low altitude mapping orbit, shows an area within the Rheasilvia basin in the south polar area of the giant asteroid Vesta.

Image credit: NASA/ JPL-Caltech/ UCLA/ MPS/ DLR/ IDA​

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Trough in Dark and Bright on Vesta​

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This image, one of the first obtained by NASA's Dawn spacecraft in its low altitude mapping orbit, shows a part of one of the troughs at the equator of the giant asteroid Vesta.

Image credit: NASA/ JPL-Caltech/ UCLA/ MPS/ DLR/ IDA​

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Crater in Shadow on Vesta​

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This image, one of the first obtained by NASA's Dawn spacecraft in its low altitude mapping orbit, shows part of the rim of a fresh crater on the giant asteroid Vesta.

Image Credit: NASA/ JPL-Caltech/ UCLA/ MPS/ DLR/ IDA​

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Buried Craters on Vesta​

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This image, one of the first obtained by NASA's Dawn spacecraft in its low altitude mapping orbit, shows many buried craters located within the equatorial trough region of the giant asteroid Vesta.

Image credit: NASA/ JPL-Caltech/ UCLA/ MPS/ DLR/ IDA​

At this detailed resolution, the surface shows abundant small craters, and textures such as small grooves and lineaments that are reminiscent of the structures seen in low-resolution data from the higher-altitude orbits. Also, this fine scale highlights small outcrops of bright and dark material.

A gallery of images can be found online at: http://www.nasa.gov/mission_pages/dawn/multimedia/gallery-index.html .

The images were returned to Earth on Dec. 13. Dawn scientists plan to acquire data in the low-altitude mapping orbit for at least 10 weeks. The primary science objectives in this orbit are to learn about the elemental composition of Vesta's surface with the gamma ray and neutron detector and to probe the interior structure of the asteroid by measuring the gravity field.

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[orb]

Universe Today: Holiday Greetings from an Alien Snowman on Vesta

Vesta Greeting Card created by Joe W - From Dawn website

Alien Snowman on Vesta
An impact structure on asteroid Vesta resembling a snowman. Credit: NASA​

SPACE.com: NASA Probe Snaps Close-Up Photos of Giant Asteroid

Universe Today: NASA’s Dawn Orbiter snaps Best Ever Images of Vesta

 

[orb]

The Planetary Society Blog: Dawn Journal: The Om of orbit adjustment