Updates Dawn Mission News

NASA / NASA JPL:
Dawn Opens its Eyes, Checks its Instruments

March 21, 2011

After a hibernation of about six months, the framing cameras on board NASA's Dawn spacecraft have again ventured a look into the stars. The spacecraft also powered up its visible and infrared mapping spectrometer, which investigates surface mineralogy, and the gamma ray and neutron detector, which detects elemental composition. The reactivation prepares the instruments for the May approach and July arrival at Vesta, Dawn's first port of call in the asteroid belt.

"Last week, we gently 'woke up' Dawn's three science instruments, which typically spend most of their time sleeping during the three-and-a-half-year journey to Vesta," said Robert Mase, Dawn project manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "This activity confirms that Dawn is on track for the first close examination of one of the last unexplored worlds of the inner solar system."

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Click on image for details​



These images of the star field demonstrate that the framing cameras on board NASA's Dawn spacecraft are functioning flawlessly.
Image credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​
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The framing camera activities were led by scientists from the Max Planck Institute for Solar System Research in Katlenburg-Lindau, Germany. "The camera system is working flawlessly. The dry run was a complete success," said Andreas Nathues, lead investigator for the framing camera, based at the Institute.

The international team of Dawn scientists and engineers in Germany and the United States spent three days interacting with the camera system, confirming the excellent health of the mechanical and electrical components and updating the software.

In the months to come, the camera system will provide images needed to navigate the spacecraft to its rendezvous with Vesta, and will begin to image the asteroid's surface. These early images on approach will be the start of a campaign to systematically map Vesta's surface in detail and will provide tantalizing clues as to its mineralogical composition. In addition, the framing cameras will search for moons in Vesta's vicinity and look for evidence of past volcanic activity.

The full release on the framing camera from Max Planck is available at: http://www.mps.mpg.de/en/aktuelles/pressenotizen/pressenotiz_20110321.html.

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Earlier news:
 
Science@NASA: Dawn Approaches Asteroid Vesta:
April 7, 2011: After 3 ½ years of thrusting silently through the void, NASA's Dawn spacecraft is on the threshold of a new world. It's deep in the asteroid belt, less than 4 months from giant asteroid Vesta.

"We're closing in," says Marc Rayman, Dawn's chief engineer and mission manager. "And I'm getting more excited every day!"

Dawn will enter orbit around Vesta in July 2011, becoming the first spacecraft ever to orbit a body in the asteroid belt. After conducting a detailed study of the uncharted alien world for a year, the spacecraft will pull off an even more impressive first. It will leave Vesta, fly to dwarf planet Ceres, and enter orbit there.

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NASA / NASA JPL:
Dawn Reaches Milestone Approaching Asteroid Vesta

May 03, 2011

PASADENA, Calif. -- NASA's Dawn spacecraft has reached its official approach phase to the asteroid Vesta and will begin using cameras for the first time to aid navigation for an expected July 16 orbital encounter. The large asteroid is known as a protoplanet -- a celestial body that almost formed into a planet.

At the start of this three-month final approach to this massive body in the asteroid belt, Dawn is 1.21 million kilometers (752,000 miles) from Vesta, or about three times the distance between Earth and the moon. During the approach phase, the spacecraft's main activity will be thrusting with a special, hyper-efficient ion engine that uses electricity to ionize and accelerate xenon. The 12-inch-wide ion thrusters provide less thrust than conventional engines, but will provide propulsion for years during the mission and provide far greater capability to change velocity.

"We feel a little like Columbus approaching the shores of the New World," said Christopher Russell, Dawn principal investigator, based at the University of California in Los Angeles (UCLA). "The Dawn team can't wait to start mapping this Terra Incognita."

Dawn previously navigated by measuring the radio signal between the spacecraft and Earth, and used other methods that did not involve Vesta. But as the spacecraft closes in on its target, navigation requires more precise measurements. By analyzing where Vesta appears relative to stars, navigators will pin down its location and enable engineers to refine the spacecraft's trajectory. Using its ion engine to match Vesta's orbit around the sun, the spacecraft will spiral gently into orbit around the asteroid. When Dawn gets approximately 16,000 kilometers (9,900 miles) from Vesta, the asteroid's gravity will capture the spacecraft in orbit.

"After more than three-and-a-half years of interplanetary travel, we are finally closing in on our first destination," said Marc Rayman, Dawn's chief engineer, at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "We're not there yet, but Dawn will soon bring into focus an entire world that has been, for most of the two centuries scientists have been studying it, little more than a pinpoint of light."

Scientists will search the framing camera images for possible moons around Vesta. None of the images from ground-based and Earth-orbiting telescopes have seen any moons, but Dawn will give scientists much more detailed images to determine whether small objects have gone undiscovered.

The gamma ray and neutron detector instrument also will gather information on cosmic rays during the approach phase, providing a baseline for comparison when Dawn is much closer to Vesta. Simultaneously, Dawn's visible and infrared mapping spectrometer will take early measurements to ensure it is calibrated and ready when the spacecraft enters orbit around Vesta.

Dawn's odyssey, which will take it on a journey of 4.8-billion kilometers (3-billion miles), began on Sept. 27, 2007, with its launch from Cape Canaveral Air Force Station in Florida. It will stay in orbit around Vesta for one year. After another long cruise phase, Dawn will arrive at its second destination, an even more massive body in the asteroid belt, called Ceres, in 2015.

These two icons of the asteroid belt will help scientists unlock the secrets of our solar system's early history. The mission will compare and contrast the two giant bodies, which were shaped by different forces. Dawn's science instrument suite will measure surface composition, topography and texture. In addition, the Dawn spacecraft will measure the tug of gravity from Vesta and Ceres to learn more about their internal structures.

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NASA JPL Blogs: Journal entry on approach phase

NASA Press Release: NASA Dawn Spacecraft Reaches Milestone Approaching Asteroid
 
NASA / NASA JPL:
NASA's Dawn Captures First Image of Nearing Asteroid

May 11, 2011

PASADENA, Calif. -- NASA's Dawn spacecraft has obtained its first image of the giant asteroid Vesta, which will help fine-tune navigation during its approach. Dawn is expected to achieve orbit around Vesta on July 16, when the asteroid is about 188 million kilometers (117 million miles) from Earth.

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This image shows the first, unprocessed image obtained by NASA's Dawn spacecraft of the giant asteroid Vesta in front of a background of stars.
Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​
|This image, processed to show the true size of the giant asteroid Vesta, shows Vesta in front of a spectacular background of stars.
Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​
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The image from Dawn's framing cameras was taken on May 3 when the spacecraft began its approach and was approximately 1.21 million kilometers (752,000 miles) from Vesta. The asteroid appears as a small, bright pearl against a background of stars. Vesta is also known as a protoplanet, because it is a large body that almost formed into a planet.

"After plying the seas of space for more than a billion miles, the Dawn team finally spotted its target," said Carol Raymond, Dawn's deputy principal investigator at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "This first image hints of detailed portraits to come from Dawn's upcoming visit."

Vesta is 530 kilometers (330 miles) in diameter and the second most massive object in the asteroid belt. Ground- and space-based telescopes obtained images of the bright orb for about two centuries, but with little surface detail.

Mission managers expect Vesta's gravity to capture Dawn in orbit on July 16. To enter orbit, Dawn must match the asteroid's path around the sun, which requires very precise knowledge of the body's location and speed. By analyzing where Vesta appears relative to stars in framing camera images, navigators will pin down its location and enable engineers to refine the spacecraft's trajectory.

Dawn will start collecting science data in early August at an altitude of approximately 1,700 miles (2,700 kilometers) above the asteroid's surface. As the spacecraft gets closer, it will snap multi-angle images, allowing scientists to produce topographic maps. Dawn will later orbit at approximately 200 kilometers (120 miles) to perform other measurements and obtain closer shots of parts of the surface. Dawn will remain in orbit around Vesta for one year. After another long cruise phase, Dawn will arrive in 2015 at its second destination, Ceres, an even more massive body in the asteroid belt.

Gathering information about these two icons of the asteroid belt will help scientists unlock the secrets of our solar system's early history. The mission will compare and contrast the two giant bodies shaped by different forces. Dawn's science instruments will measure surface composition, topography and texture. Dawn will also measure the tug of gravity from Vesta and Ceres to learn more about their internal structures. The spacecraft's full odyssey will take it on a 5-billion-kilometer (3-billion-mile) journey, which began with its launch in September 2007.

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NASA / NASA JPL:
Dawn Captures Video on Approach to Asteroid Vesta

June 13, 2011

PASADENA, Calif. – Scientists working with NASA's Dawn spacecraft have created a new video showing the giant asteroid Vesta as the spacecraft approaches this unexplored world in the main asteroid belt.

The video loops 20 images obtained for navigation purposes on June 1. The images show a dark feature near Vesta's equator moving from left to right across the field of view as Vesta rotates. Images also show Vesta's jagged, irregular shape, hinting at the enormous crater known to exist at Vesta's south pole.

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This movie shows surface details beginning to resolve as NASA's Dawn spacecraft closes in on the giant asteroid Vesta. The framing camera aboard NASA's Dawn spacecraft obtained the images used for this animation on June 1, 2011, from a distance of about 300,000 miles (483,000 kilometers).
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The images were obtained by a framing camera during a 30-minute period and show about 30 degrees of a rotation. The pixel size in these images is approaching the resolution of the best Hubble Space Telescope images of Vesta.

"Like strangers in a strange land, we're looking for familiar landmarks," said Jian-Yang Li, a Dawn participating scientist from the University of Maryland, College Park. "The shadowy spot is one of those -- it appears to match a feature, known as 'Feature B,' from images of Vesta taken by NASA's Hubble Space Telescope."

Before orbiting Vesta on July 16, Dawn will gently slow down to about 75 mph (120 kilometers per hour). NASA is expecting to release more images on a weekly basis, with more frequent images available once the spacecraft begins collecting science at Vesta.

"Vesta is coming more and more into focus," said Andreas Nathues, framing camera lead investigator, based at the Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany. "Dawn's framing camera is working exactly as anticipated."

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NASA Press Release
 
Here is the YoutubeLink
WOW!


Can't wait to see more ;-)
 
NASA:
June 20, 2011​
MEDIA ADVISORY : M11-126
NASA Hosts Briefing To Preview Spacecraft Visit Of Large Asteroid


WASHINGTON -- NASA will host a news briefing at 2 p.m. EDT [18:00 UTC] on Thursday, June 23, to discuss the Dawn spacecraft's year-long visit to the large asteroid Vesta. The mission expects to go into orbit around Vesta on July 16 and begin gathering science data in early August. The briefing will be held in the NASA Headquarters auditorium located at 300 E St. SW, in Washington. NASA Television and the agency's website will broadcast the event.

Dawn's visit to Vesta will be the first prolonged encounter to a main belt asteroid and the first trip to a protoplanet, or large body that almost became a planet. Observations will help understand the earliest chapter of our solar system's history.

The briefing panelists are:
  • W. James Adams, deputy director, Planetary Science Directorate, NASA Headquarters
  • Robert Mase, Dawn project manager, Jet Propulsion Laboratory (JPL), Pasadena, Calif.
  • Christopher Russell, Dawn principal investigator, UCLA
  • Carol Raymond, Dawn deputy principal investigator, JPL

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NASA Dawn Mission News: NASA Hosts Preview of Visit to Large Asteroid:
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The event will be held at NASA Headquarters in Washington and will be broadcast live on NASA Television and streamed at http://www.nasa.gov/ntv. In addition, the event will be carried live on Ustream, with a live chat available, at http://www.ustream.tv/nasajpl2.

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NASA / NASA JPL:
Dawn Nears Start of Year-Long Stay at Giant Asteroid

June 23, 2011

PASADENA, Calif. – NASA's Dawn spacecraft is on track to begin the first extended visit to a large asteroid. The mission expects to go into orbit around Vesta on July 16 and begin gathering science data in early August. Vesta resides in the main asteroid belt and is thought to be the source of a large number of meteorites that fall to Earth.

"The spacecraft is right on target," said Robert Mase, Dawn project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "We look forward to exploring this unknown world during Dawn's one-year stay in Vesta's orbit."

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Dawn Approaching VestaNASA's Dawn spacecraft obtained this image on its approach to the protoplanet Vesta, the second-most massive object in the main asteroid belt.
Image Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/PSI​
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Dawn's Approach to VestaThis movie shows images obtained by NASA's Dawn spacecraft on its approach to the protoplanet Vesta and a comparison of views from Dawn's framing camera and NASA's Hubble Space Telescope.
Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/PSI and NASA/ESA/STScI/UMd​
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Dawn and Hubble Views of VestaThese views of the protoplanet Vesta were obtained by NASA's Dawn spacecraft and NASA's Hubble Space Telescope.
Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/PSI and NASA/ESA/STScI/UMd​
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After traveling nearly four years and 1.7 billion miles (2.7 billion kilometers), Dawn is approximately 96,000 miles (155,000 kilometers) away from Vesta. When Vesta captures Dawn into its orbit on July 16, there will be approximately 9,900 miles (16,000 kilometers) between them. When orbit is achieved, they will be approximately 117 million miles (188 million kilometers) away from Earth.

After Dawn enters Vesta's orbit, engineers will need a few days to determine the exact time of capture. Unlike other missions where a dramatic, nail-biting propulsive burn results in orbit insertion around a planet, Dawn has been using its placid ion propulsion system to subtly shape its path for years to match Vesta's orbit around the sun.

Images from Dawn's framing camera, taken for navigation purposes, show the slow progress toward Vesta. They also show Vesta rotating about 65 degrees in the field of view. The images are about twice as sharp as the best images of Vesta from NASA's Hubble Space Telescope, but the surface details Dawn will obtain are still a mystery.

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Animation of Dawn's Visit to VestaThis movie presents a series of animations showing NASA's Dawn spacecraft journey to and operations at the giant asteroid Vesta.
NASA/JPL-Caltech​
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Vesta in Spectrometer ViewOn June 8, 2011, the visible and infrared mapping spectrometer aboard NASA's Dawn spacecraft captured the instrument's first images of Vesta that are larger than a few pixels, from a distance of about 218,000 miles(351,000 kilometers).
Image credit: NASA/JPL-Caltech/UCLA/ASI/INAF​
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Possible Piece of VestaScientists believe a large number of the meteorites that are found on Earth originate from the protoplanet Vesta.
Image credit: NASA/JPL-Caltech​
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"Navigation images from Dawn's framing camera have given us intriguing hints of Vesta, but we're looking forward to the heart of Vesta operations, when we begin officially collecting science data," said Christopher Russell, Dawn principal investigator, at UCLA. "We can't wait for Dawn to peel back the layers of time and reveal the early history of our solar system."

Dawn's three instruments are all functioning and appear to be properly calibrated. The visible and infrared mapping spectrometer, for example, has started to obtain images of Vesta that are larger than a few pixels in size. During the initial reconnaissance orbit, at approximately 1,700 miles (2,700 kilometers), the spacecraft will get a broad overview of Vesta with color pictures and data in different wavelengths of reflected light. The spacecraft will move into a high-altitude mapping orbit, about 420 miles (680 kilometers) above the surface to systematically map the parts of Vesta's surface illuminated by the sun; collect stereo images to see topographic highs and lows; acquire higher-resolution data to map rock types at the surface; and learn more about Vesta's thermal properties.

Dawn then will move even closer, to a low-altitude mapping orbit approximately 120 miles (200 kilometers) above the surface. The primary science goals of this orbit are to detect the byproducts of cosmic rays hitting the surface and help scientists determine the many kinds of atoms there, and probe the protoplanet's internal structure. As Dawn spirals away from Vesta, it will pause again at the high-altitude mapping orbit. Because the sun's angle on the surface will have progressed, scientists will be able to see previously hidden terrain while obtaining different views of surface features.

"We've packed our year at Vesta chock-full of science observations to help us unravel the mysteries of Vesta," said Carol Raymond, Dawn's deputy principal investigator at JPL. Vesta is considered a protoplanet, or body that never quite became a full-fledged planet.

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NASA: Dawn News Conference Materials
 
200 kilometers flyby... Those pics are going to be more than cool ! :thumbup: Can't wait !
 
NASA / NASA JPL:
Dawn Team Members Check out Spacecraft

July 07, 2011

Dawn Mission Status Update

Mission managers for NASA's Dawn spacecraft are studying the spacecraft's ion propulsion system after Dawn experienced a loss of thrust on June 27. Dawn team members were able to trace the episode to an electronic circuit in the spacecraft's digital control and interface unit, a subsystem that houses the circuit and a computer that provides the "brains" to Dawn's ion propulsion system. That circuit appeared to lose an electronic signal. As a result, the valves controlling the flow of xenon fuel did not open properly. Dawn automatically put itself into a more basic configuration known as "safe-communications" mode, where the spacecraft stopped some activities and turned its high-gain antenna to Earth.

Engineers were able to return the spacecraft to a normal configuration and restart the spacecraft's thrusting on June 30 by switching to a second digital control and interface unit with equivalent capabilities. One set of images for navigation purposes was not obtained on June 28 because the spacecraft was in safe-communications mode, and one other set, on July 6, was not obtained to allow the spacecraft to spend the time thrusting. Other sets of navigation images have been and will be acquired as expected. The ion propulsion system is now functioning normally.

"Dawn is still on track to get into orbit around Vesta, and thanks to the flexibility provided by our use of ion propulsion, the time of orbit capture actually will move earlier by a little less than a day," said Marc Rayman, Dawn's chief engineer and mission manager. "More importantly, the rest of Dawn's schedule is unaffected, and science collection is expected to begin as scheduled in early August."

In an unrelated event, the visible and infrared mapping spectrometer on Dawn reset itself on June 29. At the time of the reset, the instrument was gathering calibration data during the spacecraft's approach to the giant asteroid Vesta. Some of its planned observations were completed successfully before automatic sensors turned the instrument off.

On June 30, Dawn team members were able to trace the reset to an internal error in the instrument's central processing unit, though they don't yet know why the internal error occurred. By temporarily turning the instrument back on, the Dawn team confirmed that the instrument is otherwise in a normal configuration. They powered the instrument back off, as originally planned for this time. Team members are working to determine when they will turn it back on again.

After arriving at Vesta, Dawn will spend about one year orbiting the asteroid, which is also known as a protoplanet because it is a large body that almost became a planet. Data collected at Vesta will help scientists understand the earliest chapter of our solar system's history.

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NASA / NASA JPL:
NASA Spacecraft to Enter Asteroid's Orbit on July 15

July 14, 2011

PASADENA, Calif. -- On July 15, NASA's Dawn spacecraft will begin a prolonged encounter with the asteroid Vesta, making the mission the first to enter orbit around a main-belt asteroid.

The main asteroid belt lies between the orbits of Mars and Jupiter. Dawn will study Vesta for one year, and observations will help scientists understand the earliest chapter of our solar system's history.

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NASA's Dawn spacecraft obtained this image of the giant asteroid Vesta with its framing camera on July 9, 2011.
Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA​
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As the spacecraft approaches Vesta, surface details are coming into focus, as seen in a recent image taken from a distance of about 26,000 miles (41,000 kilometers). The image is available at: http://www.nasa.gov/mission_pages/dawn/multimedia/dawn-image-070911.html .

Engineers expect the spacecraft to be captured into orbit at approximately 10 p.m. PDT Friday, July 15 (1 a.m. EDT Saturday, July 16). They expect to hear from the spacecraft and confirm that it performed as planned during a scheduled communications pass that starts at approximately 11:30 p.m. PDT on Saturday, July 16 (2:30 a.m. EDT Sunday, July 17). When Vesta captures Dawn into its orbit, engineers estimate there will be approximately 9,900 miles (16,000 kilometers) between them. At that point, the spacecraft and asteroid will be approximately 117 million miles (188 million kilometers) from Earth.

"It has taken nearly four years to get to this point," said Robert Mase, Dawn project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Our latest tests and check-outs show that Dawn is right on target and performing normally."

Engineers have been subtly shaping Dawn's trajectory for years to match Vesta's orbit around the sun. Unlike other missions, where dramatic propulsive burns put spacecraft into orbit around a planet, Dawn will ease up next to Vesta. Then the asteroid's gravity will capture the spacecraft into orbit. However, until Dawn nears Vesta and makes accurate measurements, the asteroid's mass and gravity will only be estimates. So the Dawn team will need a few days to refine the exact moment of orbit capture.

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NASA Press Release: RELEASE : 11-228 - NASA Spacecraft To Enter Large Asteroid's Orbit On July 15

Here's O-F calendar event for Dawn's arrival at Vesta.​
 
Hi,
here's a scenario for Dawn, starting midnight tonight (00:00:00 15 July 2011)
You'll need the [ame="http://www.orbithangar.com/searchid.php?ID=4898"]Dawn add-on[/ame] and I recommend Nighthawk's [ame="http://www.orbithangar.com/searchid.php?ID=1801"]Asteroid Pack[/ame] for 4 Vesta. State vectors are from JPL Horizons.

Code:
BEGIN_DESC
END_DESC

BEGIN_ENVIRONMENT
  System Sol
  Date MJD  55757
END_ENVIRONMENT

BEGIN_FOCUS
  Ship Dawn
END_FOCUS

BEGIN_CAMERA
  TARGET Dawn
  MODE Extern
  POS 18.28 -109.61 35.16
  TRACKMODE GlobalFrame
  FOV 40.00
END_CAMERA

BEGIN_HUD
  TYPE Orbit
  REF AUTO
END_HUD

BEGIN_MFD Left
  TYPE Orbit
  PROJ Ship
  FRAME Ecliptic
  ALT
  REF Earth
END_MFD

BEGIN_MFD Right
  TYPE Surface
  SPDMODE 1
END_MFD


BEGIN_SHIPS
Dawn:Vessels/Dawn/Dawn
  STATUS Orbiting Sun
  RPOS  195500370248.345 -15691285846.7708 -268565142967.651
  RVEL  17228.3319139155 -2411.62235476597  10929.6606044936
  AROT -27.44 -20.03 20.60
  PRPLEVEL 0:0.460000 1:0.999017
  NAVFREQ 0 0
  ENG 1 0.0900
  AUTOATT 0
  AUTOREF 
  SPR 0 0.0763
  COVER 0 0.0000
  SOLP 1 1.0000
  XENON 195.500000
END
END_SHIPS

BEGIN_ExtMFD
END

And the current orbital elements for 4 Vesta.cfg from Horizons...
Code:
Epoch =  2011.53319644079
SemiMajorAxis =  353232206516.922
Eccentricity =  8.83287630292315E-02
Inclination =  .124522621659273
LongAscNode =  1.81347260625555
LongPerihelion =  4.4292252964182
MeanLongitude =  5.20990765054845

Cheers,
Brian
 
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