This detail of a Dawn FC (framing camera) image shows a fresh scarp rimmed crater with many boulders on the crater floor. These boulders have diameters of 100-200m, which is roughly the size of many asteroids! Also evident in this image are linear mass movement features, which originate from the rim of the crater (bottom of image) and are due to material slumping towards the center of the crater. There are also many smaller, and presumably younger, impact craters on the walls of this crater.
NASA’s Dawn spacecraft obtained this image with its framing camera on September 20th 2011. This image was taken through the camera’s clear filter. The distance to the surface of Vesta is 670km and the image resolution is about 63 meters per pixel.
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.
In this image of Vesta, taken by NASA's Dawn spacecraft just shortly before the beginning of high altitude mapping orbit, north is up and the upper right corner is to the northeast.
Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
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.
This image of the asteroid Vesta, calculated from a shape model, shows a tilted view of the topography of the south polar region. The image has a resolution of about 1,000 feet (300 meters) per pixel, and the vertical scale is 1.5 times that of the horizontal scale.
This perspective shows the topography, but removes the overall curvature of Vesta, as if the giant asteroid were flat and not rounded. An observer on Vesta would not have a view like this, because the distant features would disappear over the curvature of the horizon. (In the same way, if you were standing in North America, you would not be able to see a tall Mt. Everest in the distance, because of Earth's curvature.)
Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/PSI
Dawn launched in September 2007 and arrived at Vesta on July 15, 2011. Following a year at Vesta, the spacecraft will depart in July 2012 for the dwarf planet Ceres, where it will arrive in 2015.
Jet Propulsion Laboratory, Pasadena, Calif.
Image Credit: NASA/ JPL-Caltech/ UCLA/ MPS/ DLR/ IDA
NASA’s Dawn spacecraft obtained this image with its framing camera on September 20th 2011. This image was taken through the camera’s clear filter. The distance to the surface of Vesta is 670km and the image resolution is about 63 meters per pixel.
Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
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.
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). A rotation characterization sequence helps the scientists and engineers by giving an initial overview of the character of the surface as Vesta rotated underneath the spacecraft.
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.
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.
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.
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.
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). A rotation characterization sequence helps the scientists and engineers by giving an initial overview of the character of the surface as Vesta rotated underneath the spacecraft.
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.
This image of the asteroid Vesta, calculated from a shape model, shows a tilted view of the topography of the south polar region. The image has a resolution of about 1,000 feet (300 meters) per pixel, and the vertical scale is 1.5 times that of the horizontal scale.
This perspective shows the topography, but removes the overall curvature of Vesta, as if the giant asteroid were flat and not rounded. An observer on Vesta would not have a view like this, because the distant features would disappear over the curvature of the horizon. (In the same way, if you were standing in North America, you would not be able to see a tall Mt. Everest in the distance, because of Earth's curvature.)
Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/PSI
Dawn launched in September 2007 and arrived at Vesta on July 15, 2011. Following a year at Vesta, the spacecraft will depart in July 2012 for the dwarf planet Ceres, where it will arrive in 2015.
Contacts and sources:
Priscilla VegaJet Propulsion Laboratory, Pasadena, Calif.
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.
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