Dawn gets Big Science Boost at Best Vesta Mapping Altitude

Vesta imaged by NASA’s Dawn Asteroid Orbiter. Dawn is currently at work at the Low Altitude Mapping Orbit (LAMO) acquiring new imagery and spectra of much higher resolution compared to these images acquired at higher altitudes and is also filling in gaps of surface data. The image from Dawn’s Framing Camera, at left, was taken on July 24 at a distance of 3,200 miles soon after achieving orbit around Vesta. The mosaic from Dawn’s Visible and infrared spectrometer (VIR), at right, was acquired from High-altitude mapping orbit (HAMO). Credit: NASA/ JPL-Caltech/ UCLA/ ASI/ INAF/ IAPS. Collage: Ken Kremer

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NASA’s Dawn mission is getting a whopping boost in science observing time at the closest orbit around Asteroid Vesta as the probe passes the midway point of its 1 year long survey of the colossal space rock. And the team informs Universe Today that the data so far have surpassed all expectations and they are very excited !

Dawn’s bonus study time amounts to an additional 40 days circling Vesta at the highest resolution altitude for scientific measurements. That translates to a more than 50 percent increase beyond the originally planned length of 70 days at what is dubbed the Low Altitude Mapping Orbit, or LAMO.

“We are truly thrilled to be able to spend more time observing Vesta from low altitude,” Dr. Marc Rayman told Universe Today in an exclusive interview. Rayman is Dawn’s Engineer at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

“It is very exciting indeed to obtain such a close-up look at a world that even a year ago was still just a fuzzy blob.”

The big extension for a once-in-a-lifetime shot at up close science was all enabled owing to the hard work of the international science team in diligently handling any anomalies along the pathway through interplanetary space and since Dawn achieved orbit in July 2011, as well as to the innovative engineering of the spacecraft’s design and its revolutionary ion propulsion system.

“This is a reflection of how well all of our work at Vesta has gone from the beginning of the approach phase in May 2011,” Rayman told me.

Simulated view of Vesta from Dawn in LAMO, low altitude mapping orbit - March, 6 2012
Credit: Gregory J. Whiffen, JPL

Dawn’s initially projected 10 week long science campaign at LAMO began on Dec. 12, 2011 at an average distance of 210 kilometers (130 miles) from the protoplanet and was expected to conclude on Feb. 20, 2012 under the original timeline. Thereafter it would start spiraling back out to the High Altitude Mapping Orbit, known as HAMO, approximately 680 kilometers above the surface.

“With the additional 40 days it means we are now scheduled to leave LAMO on April 4. That’s when we begin ion thrusting for the transfer to HAMO2,” Rayman stated.

And the observations to date at LAMO have already vastly surpassed all hopes – using all three of the onboard science instruments provided by the US, Germany and Italy.

“Dawn’s productivity certainly is exceeding what we had expected,” exclaimed Rayman.

“We have acquired more than 7500 LAMO pictures from the Framing Camera and more than 1 million LAMO VIR (Visible and Infrared) spectra which afford scientists a much more detailed view of Vesta than had been planned with the survey orbit and the high altitude mapping orbit (HAMO). It would have been really neat just to have acquired even only a few of these close-up observations, but we have a great bounty!”

“Roughly around half of Vesta’s surface has been imaged at LAMO.”

Dawn mosaic of Visible and Infrared spectrometer (VIR) data of Vesta
This mosaic shows the location of the data acquired by VIR (visible and infrared spectrometer) during the HAMO (high-altitude mapping orbit) phase of the Dawn mission from August to October 2011. Dawn is now making the same observations at the now extended LAMO (low-altitude mapping orbit) phase of the Dawn mission from December 2011 to April 2012. VIR can image Vesta in a number of different wavelengths of light, ranging from the visible to the infrared part of the electromagnetic spectrum. This mosaic shows the images taken at a wavelength of 550 nanometers, which is in the visible part of the electromagnetic spectrum. During HAMO VIR obtained more than 4.6 million spectra of Vesta. It is clear from this image that the VIR observations are widely distributed across Vesta, which results in a global view of the spectral properties of Vesta’s surface. This image shows Vesta’s southern hemisphere (lower part of the image) and equatorial regions (upper part of the image). NASA’s Dawn spacecraft obtained these VIR images with its visible and infrared spectrometer in September and October 2011. The distance to the surface of Vesta is around 700 kilometers (435 miles) and the average image resolution is 170 meters per pixel. Credit: NASA/ JPL-Caltech/ UCLA/ ASI/ INAF/ IAPS

The bonus time at LAMO will now be effectively used to help fill in the gaps in surface coverage utilizing all 3 science instruments. Therefore perhaps an additional 20% to 25% extra territory will be imaged at the highest possible resolution. Some of this will surely amount to enlarged new coverage and some will be overlapping with prior terrain, which also has enormous research benefits.

“There is real value even in seeing the same part of the surface multiple times, because the illumination may be different. In addition, it helps for building up stereo,” said Rayman.

Researchers will deduce further critical facts about Vesta’s topography, composition, interior, gravity and geologic features with the supplemental measurements.

Successive formation of impact craters on Vesta
This Dawn FC (framing camera) image shows two overlapping impact craters and was taken on Dec. 18,2011 during the LAMO (low-altitude mapping orbit) phase of the mission. The large crater is roughly 20 kilometers (12 miles) in diameter and the smaller crater is roughly 6 kilometers (4 miles) in diameter. The rims of the craters are both reasonably fresh but the larger crater must be older because the smaller crater cuts across the larger crater’s rim. As the smaller crater formed it destroyed a part of the rim of the pre-existing, larger crater. The larger crater’s interior is more densely cratered than the smaller crater, which also suggests that is it older. In the bottom of the image there is some material slumping from rim of the larger crater towards its center. This image with its framing camera on Dec. 18, 2011. This image was taken through the camera’s clear filter. The distance to the surface of Vesta is 260 kilometers (162 miles) and the image has a resolution of about 22 meters (82 feet) per pixel. Credit: NASA/ JPL-Caltech/ UCLA/ MPS/ DLR/ IDA

The foremost science goals at LAMO are collection of gamma ray and neutron measurements with the GRaND instrument – which focuses on determining the elemental abundances of Vesta – and collection of information about the structure of the gravitational field. Since GRaND can only operate effectively at low orbit, the extended duration at LAMO takes on further significance.

“Our focus is on acquiring the highest priority science. The pointing of the spacecraft is determined by our primary scientific objectives of collecting GRaND and gravity measurements.”

As Dawn continues orbiting every 4.3 hours around Vesta during LAMO, GRaND is recording measurements of the subatomic particles that emanate from the surface as a result of the continuous bombardment of cosmic rays and reveals the signatures of the elements down to a depth of about 1 meter.

“You can think of GRaND as taking a picture of Vesta but in extremely faint light. That is, the nuclear emissions it detects are extremely weak. So our long time in LAMO is devoted to making a very, very long exposure, albeit in gamma rays and neutrons and not in visible light,” explained Rayman.

Now with the prolonged mission at LAMO the team can gather even more data, amounting to thousands and thousands more pictures, hundreds of thousands of more VIR spectra and ultra long exposures by GRaND.

“HAMO investigations have already produced global coverage of Vesta’s gravity field,” said Sami Asmar, a Dawn co-investigator from JPL. Extended investigations at LAMO will likewise vastly improve the results from the gravity experiment.

Dawn Spacecraft Current Location and Trajectory - March, 6 2012. Credit: Gregory J. Whiffen, JPL

“We always carried 40 days of “margin,” said Rayman, “but no one who was knowledgeable about the myriad challenges of exploring this uncharted world expected we would be able to accomplish all the complicated activities before LAMO without needing to consume some of that margin. So although we recognized that we might get to spend some additional time in LAMO, we certainly did not anticipate it would be so much.”

“As it turned out, although we did have surprises the operations team managed to recover from all of them without using any of those 40 days.”

“This is a wonderful bonus for science,” Rayman concluded.

“We remain on schedule to depart Vesta in July 2012, as planned for the past several years.”

Dawn’s next target is Ceres, the largest asteroid in the main Asteroid Belt between Mars and Jupiter

Asteroid Vesta Floats in Space in High Resolution 3-D

Vesta’s Eastern Hemisphere Floats in Space in 3-D. This anaglyph shows the varied topography of Vesta’s eastern hemisphere from craters in the north, the equatorial troughs and the huge mountain at the Souh Pole. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

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The giant Asteroid Vesta literally floats in space in a new high resolution 3-D image of the battered bodies Eastern Hemisphere taken by NASA’s Dawn Asteroid Orbiter.

Haul out your red-cyan 3-D anaglyph glasses and lets go whirling around Vesta and sledding down mountains to greet the alien Snowman! The sights are fabulous !

The Dawn imaging group based at the German Aerospace Center (DLR), in Berlin, Germany and led by team member Ralf Jaumann has released a trio of new high resolution 3-D images that are the most vivid anaglyphs yet published by the international science team.

The lead anaglyph shows the highly varied topography of the Eastern Hemisphere of Vesta and was taken during the final approach phase as Dawn was about 5,200 kilometers (3,200 miles) away and preparing to achieve orbit in July 2011.

The heavily cratered northern region is at top and is only partially illuminated because of Vesta’s tilted angle to the Sun at that time of year. Younger craters are overlain onto many older and more degraded craters. The equatorial region is dominated by the mysterious troughs which encircle most of Vesta and may have formed as a result of a gargantuan gong, eons ago.

The southern hemisphere exhibits fewer craters than in the northern hemisphere. Look closely at the bottom left and you’ll see the huge central mountain complex of the Rheasilvia impact basin visibly protruding out from Vesta’s south polar region.

This next 3-D image shows a close-up of the South Pole Mountain at the center of the Rheasilvia Impact basin otherwise known as the “Mount Everest of Vesta”.

The Mount Everest of Vesta in 3-D
This anaglyph shows the central complex and huge mountain in Vesta’s Rheasilvia impact basin at the South Pole. Does water ice lurk beneath the South Pole ?
Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

The central complex is approximately 200 kilometers (120 miles) in diameter and is approximately 20 kilometers (12 miles) tall and is therefore about two and a half times taller than Earth’s Mount Everest!

Be sure to take a long look inside the deep craters and hummocky terrain surrounding “Mount Everest”.

A recent study concludes that, in theory, Vesta’s interior is cold enough for water ice to lurk beneath the North and South poles.

Finally lets gaze at the trio of craters that make up the “Snowman” in the 3-D image snapped in August 2011 as Dawn was orbiting at about 2,700 kilometers (1,700 miles) altitude. The three craters are named Minucia, Marcia and Calpurnia from top to bottom. Their diameters respectively are; 24 kilometers (15 miles), 53 kilometers (33 miles) and 63 kilometers (40 miles).

3-D image of Vesta’s “Snowman” craters
The three craters are named Minucia, Marcia and Calpurnia from top to bottom. They are 24 kilometers (15 miles), 53 kilometers (33 miles) and 63 kilometers (40 miles) in diameter, respectively. Image resolution is about 250 meters (820 feet) per pixel. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

It is likely that Marcia and Calpurnia formed from the impact of a binary asteroid and that Minucia formed in a later impact. The smooth region around the craters is the ejecta blanket.

Dawn Orbiting Vesta above the “Snowman” craters
This artist's concept shows NASA's Dawn spacecraft orbiting the giant asteroid Vesta above the Snowman craters. The depiction of Vesta is based on images obtained by Dawn's framing cameras. Dawn is an international collaboration of the US, Germany and Italy. Credit: NASA/JPL-Caltech

Vesta is the second most massive asteroid in the main Asteroid Belt between Mars and Jupiter. It is 330 miles (530 km) in diameter.

Dawn is the first spacecraft from Earth to visit Vesta. It achieved orbit in July 2011 for a year long mission. Dawn will fire up its ion propulsion thrusters in July 2012 to spiral out of orbit and sail to Ceres, the biggest asteroid of them all !

Vesta and Ceres are also considered to be protoplanets.

Does Water Ice Lurk Beneath the Poles of Vesta ?

Viewing the South Pole of Vesta and Rhea Silvia Impact Basin. This image obtained by Dawn’s framing camera shows the south pole of the giant asteroid Vesta and the circular Rheasilvia impact basin which scientists believe originated by a collision with another asteroid early in the asteroid's history. The image was recorded from a distance of about 1,700 miles (2,700 kilometers). The image resolution is about 260 meters per pixel. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

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The mysterious asteroid Vesta may well have more surprises in store. Despite past observations that Vesta would be nearly bone dry, newly published research indicates that about half of the giant asteroid is sufficiently cold and dark enough that water ice could theoretically exist below the battered surface.

Scientists working at NASA’s Goddard Space Flight Center in Greenbelt, Md., and the University of Maryland have derived the first models of Vesta’s average global temperatures and illumination by the Sun based on data obtained from the Hubble Space Telescope.

“Near the north and south poles, the conditions appear to be favorable for water ice to exist beneath the surface,” says Timothy Stubbs of NASA’s Goddard Space Flight Center in Greenbelt, Md., and the University of Maryland, Baltimore County. The research by Timothy Stubbs and Yongli Wang, of the Goddard Planetary Heliophysics Institute at the University of Maryland, was published in the January 2012 issue of the journal Icarus.

If any water lurks beneath Vesta, it would most likely exist at least 10 feet (3 meters) below the North and South poles because the models predict that the poles are the coldest regions on the giant asteroid and the equatorial regions are too warm.

Global Map of Average Surface Temperature of Vesta
This global map of average surface temperature shows the warmer equatorial zone of the giant asteroid Vesta is likely too warm to sustain water ice below the surface. But roughly half of Vesta is so cold and receives so little sunlight on average that water ice could have survived there for billions of years. The dividing lines (solid gray) are found at about 27 degrees north latitude and 27 degrees south latitude. This map, with temperatures given in kelvins, comes from the first published models of the average global temperature and illumination conditions on Vesta. Credit: NASA/GSFC/UMBC

If proven, the existence of water ice at Vesta would have vast implications for the formation and evolution of the tiny body and upend current theories.

The surface of Vesta is not cold enough for ice to survive all the time because unlike the Moon, it probably does not have any significant permanently shadowed craters where water ice could stay frozen on the surface indefinitely.

Even the huge 300 mile diameter (480-kilometer) crater at the South Pole is not a good candidate for water ice because Vesta is tilted 27 degrees on its axis, a bit more than Earth’s tilt of 23 degrees.

By contrast, the Moon is only tilted 1.5 degrees and possesses many permanently shadowed craters. NASA’s LCROSS impact mission proved that water ice exists inside permanently shadowed lunar craters.

New modeling shows that, under present conditions, Vesta's polar regions are cold enough (less than about 145 kelvins) to sustain water ice for billions of years, as this map of average surface temperature around the asteroid's south pole indicates.

The models predict that the average annual temperature around Vesta’s poles is below minus 200 degrees Fahrenheit (145 kelvins). Water ice is not stable above that temperature in the top 10 feet of Vestan soil, or regolith.

At the equator and in a band stretching to about 27 degrees north and south in latitude, the average annual temperature is about minus 190 degrees Fahrenheit (145 kelvins), which is too high for the ice to survive.

“On average, it’s colder at Vesta’s poles than near its equator, so in that sense, they are good places to sustain water ice,” says Stubbs in a NASA statement. “But they also see sunlight for long periods of time during the summer seasons, which isn’t so good for sustaining ice. So if water ice exists in those regions, it may be buried beneath a relatively deep layer of dry regolith.”

Vesta is the second most massive asteroid in the main Asteroid belt between Mars and Jupiter.

NASA’s Dawn Asteroid Orbiter is the very first mission to Vesta and achieved orbit in July 2011 for a 1 year long mission.

Dawn is currently circling Vesta at its lowest planned orbit. The three science instruments are snapping pictures and the spectrometers are collecting data on the elemental and mineralogical composition of Vesta.

The onboard GRaND spectrometer in particular could shed light on the question of whether water ice exists at Vesta.

So far no water has been detected, but the best data is yet to come.

In July 2012, Dawn fires up its ion thrusters and spirals out of orbit to begin the journey to Ceres, the largest asteroid of them all.

Ceres is believed to harbor huge caches of water, either as ice or in the form of oceans and is a potential habitat for life.

NASA’s Dawn Orbiter snaps Best Ever Images of Vesta

Crater in Shadow on Vesta. This new image from Dawn in its low altitude mapping orbit on Dec. 13 shows part of the rim of a fresh crater on Vesta located in an area known as the Heavily Cratered Terrain in the northern hemisphere at around 17 degrees latitude and 77 degrees longitude. It was obtained at an altitude of 119 miles (191 km) and covers an area 11 mi x 11 mi (18 km x 18 km). Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

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NASA’s Dawn spacecraft has swooped down to the closest orbit above the monster asteroid Vesta that the craft’s cameras and spectrometers will ever glimpse and the probe has begun transmitting these highest resolution pictures to anxiously waiting scientists back on Earth.

Dawn arrived at its Low Altitude Mapping Orbit, known as LAMO, on Dec. 12, 2011 and will continue circling scarcely 130 miles (210 kilometers) above Vesta for at least the next 10 weeks. Each orbit takes about 4.3 hours.

NASA has now released the first batch of crisp new close-ups images taken by the Framing Camera on Dec. 13 showing the stippled and lumpy surface in an exquisitely fine detail never seen before.

The photo montage below shows side by side views of the same portion of the Vestan surface at ever increasing resolution and clarity from ever lower altitudes.

Closer and Closer to the Vesta Surface
NASA’s Dawn spacecraft has spiraled closer and closer to the surface of the giant asteroid Vesta since arriving in mid-2011. The two images on the left represent an identical area, first observed during Dawn's survey orbit (far left image). The picture in the center is from Dawn's high-altitude mapping orbit (HAMO) from an altitude of about 430 miles (700 km) with about 230 feet (70 meters-per-pixel) resolution. The image at right was obtained on Dec. 13 from the low altitude mapping orbit (LAMO) at an altitude of 124 miles (199 km) above the surface and has a resolution of 75 feet (23 m) per pixel. It shows small impact craters or slumping at the steep-flanked mountain in the image center that can be identified in the two images to the left. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

The high resolution image gallery reveals fine scale highlights such as multitudes of small craters, grooves and lineaments, landslides and slumping, ejecta from past colossal impacts, and small outcrops of bright and dark materials.

The science team, led by Principal Investigator Prof Chris Russell of UCLA, believes that Vesta is actually more like a planet than an asteroid based on the data obtained thus far.

Vesta is the smallest terrestrial planet in our Solar System”, Russell told Universe Today. “We do not have a good analog to Vesta anywhere else in the Solar System.”

The primary science objectives at the LAMO orbit are to measure the elemental abundances on the surface of Vesta with the US built gamma ray and neutron detector (GRaND) and to probe the interior structure of the asteroid by measuring the gravity field.

Vesta is a proto-planet formed just a few million years after the birth of the solar system whose evolution into a larger planet was stopped cold by the massive gravitational influence of the planet Jupiter.

Scientists are plowing through thousands of images and millions of spectral measurements to glean clues about the origin and evolution of the solar system that have been preserved on the hitherto unexplored world.

Buried Craters on Vesta
This Dec. 13 image from Dawn spacecraft in its low altitude mapping orbit shows many buried craters located within the equatorial trough region of Vesta. This area bears traces of the material thrown out by the impact that created the Rheasilvia basin in the asteroid’s south polar region. Lineated features are visible in a variety of shapes and sizes from an altitude of 117 miles (189 km) over an area of 11 mi x 11 mi (18 km x 18 km). Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

“Vesta is a transitional body between a small asteroid and a planet and is unique in many ways,” says mission scientist Vishnu Reddy of the Max Planck Institute for Solar System Research in Katlenburg-Lindau, Germany. “Vesta is unlike any other asteroid we have visited so far.”

After completing the LAMO measurements, Dawn will again spiral back to a higher altitude for further data gathering especially at the unseen North Pole which is in darkness now.

Dawn will continue orbiting Vesta until July 2012 when it will fire up its ion propulsion system and depart for Ceres, the largest body in the main Asteroid belt between Mars and Jupiter.

“What can be more exciting than to explore an alien world that until recently was virtually unknown!” Dr. Marc Rayman told Universe Today. Rayman is Dawn’s Chief Engineer from NASA’s Jet Propulsion Lab (JPL) in Pasadena, Calif.

Equatorial Trough in Dark and Bright on Vesta
This image was one of the first obtained by Dawn in its low altitude mapping orbit and shows a part of one of the long troughs at the equator of Vesta. Credit: NASA/ JPL-Caltech/ UCLA/ MPS/ DLR/ IDA

“Dawn continues to gather gamma ray spectra and neutron spectra,” Rayman reports. “The bonus imaging at LAMO is yielding pictures more than three times better than those acquired in the high altitude mapping orbit (HAMO). Every week at this low altitude, Dawn will use its ion propulsion system to fine tune its orbit. The first of these weekly orbit adjustments was performed on December 17.”

The framing cameras eere built by the Max Planck Institute for Solar System Research in Germany.

A treasure trove of spectacular Vesta close-ups are streaming at this moment to the home planet and we’ll have many more goodies to show.

Read continuing features about Dawn by Ken Kremer starting here:
Holiday Greetings from an Alien Snowman on Vesta
Dawn swoops to lowest orbit around Vesta – Unveiling Spectacular Alien World
Rainbow of Colors Reveal Asteroid Vesta as More Like a Planet
Vrooming over Vivid Vestan Vistas in Vibrant 3 D – Video
NASA Planetary Science Trio Honored as ‘Best of What’s New’ in 2011- Curiosity/Dawn/MESSENGER
Dawn Discovers 2nd Giant South Pole Impact Basin at Strikingly Dichotomous Vesta
Amazing New View of the Mt. Everest of Vesta
Dramatic 3 D Imagery Showcases Vesta’s Pockmarked, Mountainous and Groovy Terrain

Holiday Greetings from an Alien Snowman on Vesta

Holiday Greetings from an Alien Snowman on Vesta - to all inhabitants of the Galaxy

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Celebrate the winter holiday season in the company of an ‘Alien Snowman’ on the asteroid Vesta, someone we didn’t even have a clue about until six months ago.

Vesta and the Snowman have been transformed into the beautiful banner above – sent to me courtesy of the Dawn mission team to share with the readers of Universe Today.

Now you can be a creative artist and use the striking new images of Vesta to fashion your own greeting cards (see below) and send seasonal tidings of winter holiday cheer not possible before – all thanks to the remarkably insightful discoveries of Dawn’s international science team.

Vesta Greeting Card created by Joe W - From Dawn website

The Dawn spacecraft orbiting the giant asteroid Vesta is one of NASA’s crowning scientific accomplishments of 2011 because it’s cameras and spectrometers have unveiled a mysteriously diverse world that has no match elsewhere in our solar system.

The more we explore the unknown the more we are enlightened as to just how limited our view of the Universe is from within the narrow confines of our miniscule abode.

Vesta Greeting Card created by Judy C - From Dawn website
Hey, Let's go skiing at the South Pole !

The Kepler Space Telescopes latest discoveries of Earth-sized worlds are just the latest examples guiding us to a clearer understanding of our place in the Universe.

Vesta Greeting Card created by Jillian S - From Dawn website

Here are just a few of the Vestan images you can masterfully decorate – the Snowman, The Mount Everest of Vesta and the cataclysmically bombarded South Pole.

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

So, let you imaginations run wild with wintery scenes to match the majesty of this matchless world. The Dawn Education and Public Outreach (EPO) team has created several templates which you can access here

Of course you can also use any of the images posted at the Dawn mission website.

The Mount Everest of Vesta
Image of asteroid Vesta calculated from a shape model, showing a tilted view of the topography of the south polar region. This perspective shows the topography, but removes the overall curvature of Vesta, as if the giant asteroid were flat and not rounded. Credit: NASA
Shattered South Pole of Vesta
This Dawn framing camera image shows scarps, hummocky (eg. wavy/ undulating) terrain and impacts in Vesta's south polar region. Credit: NASA

And feel free to post your inspired creations here at Universe Today.

Vesta is the second most massive object in the main Asteroid Belt between Mars and Jupiter.

Dawn arrived in orbit at Vesta in July 2011 for the first ever close up studies of the shattered celestial body. Dawn will spend a year investigating Vesta before spiraling out towards Ceres, the largest asteroid.

Read continuing features about Dawn by Ken Kremer starting here:
Dawn swoops to lowest orbit around Vesta – Unveiling Spectacular Alien World
Rainbow of Colors Reveal Asteroid Vesta as More Like a Planet
Vrooming over Vivid Vestan Vistas in Vibrant 3 D – Video
NASA Planetary Science Trio Honored as ‘Best of What’s New’ in 2011- Curiosity/Dawn/MESSENGER
Dawn Discovers Surprise 2nd Giant South Pole Impact Basin at Strikingly Dichotomous Vesta
Amazing New View of the Mt. Everest of Vesta
Dramatic 3 D Imagery Showcases Vesta’s Pockmarked, Mountainous and Groovy Terrain
Rheasilvia – Super Mysterious South Pole Basin at Vesta
Space Spectacular — Rotation Movies of Vesta
3 D Alien Snowman Graces Vesta
NASA Unveils Thrilling First Full Frame Images of Vesta from Dawn
Dawn Spirals Down Closer to Vesta’s South Pole Impact Basin

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

Dawn Orbiting Vesta. This artist's concept shows NASA's Dawn spacecraft orbiting the giant asteroid Vesta. The depiction of Vesta is based on images obtained by Dawn's framing cameras. Dawn is an international collaboration of the US, Germany and Italy. Credit: NASA/JPL-Caltech

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NASA’s Dawn Asteroid Orbiter successfully spiraled down today to the closest orbit the probe will ever achieve around the giant asteroid Vesta, and has now begun critical science observations that will ultimately yield the mission’s highest resolution measurements of this spectacular body.

“What can be more exciting than to explore an alien world that until recently was virtually unknown!” Dr. Marc Rayman gushed in an exclusive interview with Universe Today. Rayman is Dawn’s Chief Engineer from NASA’s Jet Propulsion Lab (JPL) in Pasadena, Calif., and a protégé of Star Trek’s Mr. Scott.

Before Dawn, Vesta was little more than a fuzzy blob in the world’s most powerful telescopes. Vesta is the second most massive object in the main Asteroid Belt between Mars and Jupiter.

Dawn is now circling about Vesta at the lowest planned mapping orbit, dubbed LAMO for Low Altitude Mapping Orbit. The spacecraft is orbiting at an average altitude of barely 130 miles (210 kilometers) above the heavily bombarded and mysterious world that stems from the earliest eons of our solar system some 4.5 Billion years ago. Each orbit takes about 4.3 hours.

“It is both gratifying and exciting that Dawn has been performing so well,” Rayman told me.

Dawn Orbiting Over Vesta - A Hi Res Taste of What's Ahead!
This image of the giant asteroid Vesta was obtained by Dawn 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. Low altitude mapping orbit is the closest orbit Dawn will be making, at an average of 130 miles (210 kilometers) above the giant asteroid's surface. The framing camera obtained this image of an area in the northern mid-latitudes of Vesta from an altitude of about 140 miles (230 kilometers). Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Dawn arrived in orbit at Vesta in July 2011 after a nearly 4 year interplanetary cruise since blasting off atop a Delta II rocket from Cape Canaveral, Florida in September 2007. The probe then spent the first few weeks at an initial science survey altitude of about 1,700 miles (2,700 kilometers).

Gradually the spaceship spiraled down closer to Vesta using her ion propulsion thrusters.

See Vesta science orbit diagram, below, provided courtesy of Dr. Marc Rayman.

Along the way, the international science and engineering team commanded Dawn to make an intermediate stop this past Fall 2011 at the High Altitude Mapping orbit altitude (420 miles, or 680 kilometers).

“It is so cool now to have reached this low orbit [LAMO]. We already have a spectacular collection of images and other fascinating data on Vesta, and now we are going to gain even more,” Rayman told me.

“We have a great deal of work ahead to acquire our planned data here, and I’m looking forward to every bit!

Dawn will spend a minimum of 10 weeks acquiring data at the LAMO mapping orbit using all three onboard science instruments, provided by the US, Germany and Italy.

While the framing cameras (FC) from Germany and the Visible and Infrared Mapping spectrometer (VIR) from Italy will continue to gather mountains of data at their best resolution yet, the primary science focus of the LAMO orbit will be to collect data from the gamma ray and neutron detector (GRaND) and the gravity experiment.

GRaND will measure the elemental abundances on the surface of Vesta by studying the energy and neutron by-products that emanate from it as a result of the continuous bombardment of cosmic rays. The best data are obtained at the lowest altitude.

Dawn spacecraft - Science orbits at Vesta
Credit: NASA/JPL-Caltech/Marc Rayman

By examining all the data in context, scientists hope to obtain a better understanding of the formation and evolution of the early solar system.

Vesta is a proto-planet, largely unchanged since its formation, and whose evolution into a larger planet was stopped cold by the massive gravitational influence of the planet Jupiter.

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 investigating Vesta for about a year, the engineers will ignite Dawn’s ion propulsion thrusters and blast away to Ceres, the largest asteroid which may harbor water ice and is another potential outpost for extraterrestrial life

Dawn will be the first spaceship to orbit two worlds and is also the first mission to study the asteroid belt in detail.

Asteroid Vesta from Dawn - Exquisite Clarity from a formerly Fuzzy Blob
NASA's Dawn spacecraft obtained this image of the giant asteroid Vesta with its framing camera on July 24, 2011. It was taken from a distance of about 3,200 miles (5,200 kilometers). Before Dawn, Vesta was just a fuzzy blob in the most powerful telescopes. Dawn entered orbit around Vesta on July 15, and will spend a year orbiting the body before firing up the ion propulsion system to break orbit and speed to Ceres, the largest Asteroid. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
South Polar Region of Vesta - Enhanced View
An ancient cosmic collision blasted away much of the south pole of Vesta, leaving behind an enoumous mountain about 3 times the height of Mt. Everest. NASA's Dawn spacecraft obtained this image centered on the south pole of Vesta with its framing camera on July 18, 2011 as it passed the terminator. The image has been enhanced to bring out more surface details. It was taken from a distance of about 6,500 miles (10,500 kilometers) away from the protoplanet Vesta. The smallest detail visible is about 1.2 miles (2.0 km). Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA. Enhanced and annotated by Ken Kremer

Read continuing features about Dawn by Ken Kremer starting here:

Rainbow of Colors Reveal Asteroid Vesta as More Like a Planet
Vrooming over Vivid Vestan Vistas in Vibrant 3 D – Video
NASA Planetary Science Trio Honored as ‘Best of What’s New’ in 2011- Curiosity/Dawn/MESSENGER
Dawn Discovers Surprise 2nd Giant South Pole Impact Basin at Strikingly Dichotomous Vesta
Amazing New View of the Mt. Everest of Vesta
Dramatic 3 D Imagery Showcases Vesta’s Pockmarked, Mountainous and Groovy Terrain
Rheasilvia – Super Mysterious South Pole Basin at Vesta
Space Spectacular — Rotation Movies of Vesta
3 D Alien Snowman Graces Vesta
NASA Unveils Thrilling First Full Frame Images of Vesta from Dawn
Dawn Spirals Down Closer to Vesta’s South Pole Impact Basin

Rainbow of Colors Reveal Asteroid Vesta as More Like a Planet

'Rainbow-Colored Palette' of Southern Hemisphere of Asteroid Vesta from NASA Dawn Orbiter. This mosaic using color data obtained by the framing camera aboard NASA's Dawn spacecraft shows Vesta's southern hemisphere in false color, centered on the Rheasilvia impact basin, about 290 miles (467 kilometers) in diameter with a central mound reaching about 14 miles (23 kilometers) high. The black hole in the middle is data that have been omitted due to the angle between the sun, Vesta and the spacecraft. The green areas suggest the presence of the iron-rich mineral pyroxene or large-sized particles. This mosaic was assembled using images obtained during Dawn's approach to Vesta, at a resolution of 480 meters per pixel. The German Aerospace Center and the Max Planck Institute for Solar System Research provided the Framing Camera instrument and funding as international partners on the mission team. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

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The giant Asteroid Vesta is among the most colorful bodies in our entire solar system and it appears to be much more like a terrestrial planet than a mere asteroid, say scientists deciphering stunning new images and measurements of Vesta received from NASA’s revolutionary Dawn spacecraft. The space probe only recently began circling about the huge asteroid in July after a four year interplanetary journey.

Vesta is a heavily battered and rugged world that’s littered with craters and mysterious grooves and troughs. It is the second most massive object in the Asteroid Belt and formed at nearly the same time as the Solar System some 4.5 Billion years ago.

“The framing cameras show Vesta is one of the most colorful objects in the solar system,” said mission scientist Vishnu Reddy of the Max Planck Institute for Solar System Research in Katlenburg-Lindau, Germany. “Vesta is unlike any other asteroid we have visited so far.”

Scientists presented the new images and findings from Dawn at the American Geophysical Union meeting this week in San Francisco.

Dawn is the first man-made probe to go into orbit around Vesta.

Comparative View of Terrains on Vesta - Oppia Crater
This image of Oppia Crater combines two separate views of the giant asteroid Vesta obtained by Dawn's framing camera. The far-left image uses near-infrared filters where red is used to represent 750 nanometers, green represents 920 nanometers and blue represents 980 nanometers. The image on the right is an image with colors assigned by scientists, representing different rock or mineral types on Vesta. The data reveal a world of many varied, well-separated layers and ingredients. The reddish color suggests a steep visible spectral slope, and areas of fresh landslides in the inner walls of the crater show deeper green colors. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

“Vesta is a transitional body between a small asteroid and a planet and is unique in many ways,” Reddy said. “We do not know why Vesta is so special.”

Although many asteroids look like potatoes, Reddy said Vesta reminds him more of an avocado.

Asteroid Vesta is revealed as a ‘rainbow-colored palette’ in a new image mosaic (above) showcasing this alien world of highly diverse rock and mineral types of many well-separated layers and ingredients.

Researchers assigned different colors as markers to represent different rock compositions in the stunning new mosaic of the asteroid’s southern hemisphere.

The green areas in the mosaic suggest the presence of the iron-rich mineral pyroxene or large-sized particles, according to Eleonora Ammannito, from the Visible and Infrared (VIR) spectrometer team of the Italian Space Agency. The ragged surface materials are a mixture of rapidly cooled surface rocks and a deeper layer that cooled more slowly.

What could the other colors represent?

“The surface is very much consistent with the variability in the HED (Howardite-Eucritic-Diogenite) meteorites,” Prof. Chris Russell, Dawn Principal Investigator (UCLA) told Universe Today in an exclusive interview.

“There is Diogenite in varying amounts.”

“The different colors represent in part different ratios of Diogenite to Eucritic material. Other color variation may be due to particle sizes and to aging,” Russell told me.

No evidence of volcanic materials has been detected so far, said David Williams, Dawn participating scientist of Arizona State University, Tucson.

Fresh Impact Craters on Asteroid Vesta
The fresh impact craters in this view are located in the south polar region, which has been partly covered by landslides from the adjacent crater. This would suggest that a layer of loose material covers the Vesta surface. This image combines two separate views of the giant asteroid Vesta obtained by Dawn’s framing camera. The far-left image uses near-infrared filters where red is used to represent 750 nanometers, green represents 920 nanometers and blue represents 980 nanometers. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Before Dawn arrived, researchers expected to observe indications of volcanic activity. So, the lack of findings of volcanism is somewhat surprising. Williams said that past volcanic activity may be masked due to the extensive battering and resultant mixing of the surface regolith.

“More than 10,000 high resolution images of Vesta have been snapped to date by the framing cameras on Dawn,” Dr. Marc Rayman told Universe Today. Rayman is Dawn’s Chief Engineer from NASA’s Jet Propulsion Lab (JPL) in Pasadena, Calif.

Dawn will spend a year in orbit at Vesta and investigate the asteroid at different altitudes with three on-board science instruments from the US, Germany and Italy.

The probe will soon finish spiraling down to her lowest mapping orbit known as LAMO (Low Altitude Mapping Orbit), approximately 130 miles (210 kilometers) above Vesta’s surface.

“Dawn remains on course to begin its scientific observations in LAMO on December 12,” said Rayman.

The German Aerospace Center and the Max Planck Institute for Solar System Research provided the Framing Camera instrument and funding as international partners on the mission team. The Visible and Infrared Mapping camera was provided by the Italian Space Agency.

In July 2012, Rayman and the engineering team will fire up Dawn’s ion propulsion system, break orbit and head to Ceres, the largest asteroid and what a number of scientists consider to be a planet itself.

Ceres is believed to harbor thick caches of water ice and therefore could be a potential candidate for life.

Southern Hemisphere of Vesta -Rheasilvia and Older Basin
Colorized shaded-relief map showing location of 375-kilometer-wide Older impact basin that is overlapping with the more recent 500 km (300 mi) wide Rheasilvia impact structure at asteroid Vesta’s South Pole. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
Asteroid Vesta from Dawn - Exquisite Clarity from a formerly Fuzzy Blob
NASA's Dawn spacecraft obtained this image of the giant asteroid Vesta with its framing camera on July 24, 2011. It was taken from a distance of about 3,200 miles (5,200 kilometers). Before Dawn, Vesta was just a fuzzy blob in the most powerful telescopes. Dawn entered orbit around Vesta on July 15, and will spend a year orbiting the body before firing up the ion propulsion system to break orbit and speed to Ceres, the largest Asteroid. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Read continuing features about Dawn by Ken Kremer starting here:

Vrooming over Vivid Vestan Vistas in Vibrant 3 D – Video
NASA Planetary Science Trio Honored as ‘Best of What’s New’ in 2011- Curiosity/Dawn/MESSENGER
Dawn Discovers Surprise 2nd Giant South Pole Impact Basin at Strikingly Dichotomous Vesta
Amazing New View of the Mt. Everest of Vesta
Dramatic 3 D Imagery Showcases Vesta’s Pockmarked, Mountainous and Groovy Terrain
Rheasilvia – Super Mysterious South Pole Basin at Vesta
Space Spectacular — Rotation Movies of Vesta
3 D Alien Snowman Graces Vesta
NASA Unveils Thrilling First Full Frame Images of Vesta from Dawn
Dawn Spirals Down Closer to Vesta’s South Pole Impact Basin
First Ever Vesta Vistas from Orbit – in 2D and 3D
Dawn Exceeds Wildest Expectations as First Ever Spacecraft to Orbit a Protoplanet – Vesta

Vrooming over Vivid Vestan Vistas in Vibrant 3 D – Video

Vivid Vesta Vista in Vibrant 3 D from NASA’s Dawn Asteroid Orbiter. Vesta is the second most massive asteroid and is 330 miles (530 km) in diameter. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

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It’s time to put on your 3-D glasses and go soaring all over the giant asteroid Vesta – thanks to the superlative efforts of Dawn’s international science team.

Now you can enjoy vivid ‘Vestan Vistas’ like you’ve never ever seen before in a vibrant 3 D video newly created by Dawn team member Ralf Jaumann, of the German Aerospace Center (DLR) in Berlin, Germany – see below.

To fully appreciate the rough and tumble of the totally foreign and matchless world that is Vesta, you’ll absolutely have to haul out your trusty red-cyan (or red-blue) 3 D anaglyph glasses.

Then hold on, as you glide along for a global gaze of mysteriously gorgeous equatorial groves ground out by a gargantuan gong, eons ago.

Along the way you’ll see an alien ‘Snowman’ and the remnants of the missing South Pole, including the impressive Rheasilvia impact basin – named after a Vestal virgin – and the massive mountain some 16 miles (25 kilometers) high, or more than twice the height of Mt. Everest.


Video Caption: This 3-D video incorporates images from the framing camera instrument aboard NASA’s Dawn spacecraft from July to August 2011. The images were obtained as Dawn approached Vesta and circled the giant asteroid during the mission’s survey orbit phase at an altitude of about 1,700 miles (2,700 kilometers). To view this video in 3-D use red-green, or red-blue, glasses (left eye: red; right eye: green/blue). Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

“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.”

NASA’s Dawn spacecraft is humanity’s first probe to investigate Vesta, the second most massive body in the main Asteroid Belt between Mars and Jupiter.


Video caption: 2 D rotation movie of Vesta. Compare the 2 D movie to the new 3 D movie. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

Indeed Dawn was just honored by Popular Science magazine and recognized as one of three NASA Planetary Science missions to earn a ‘Best of What’s New in 2011’ for innovation in the aviation and space category – along with the Curiosity Mars Science Laboratory (MSL) and MESSENGER Mercury orbiter.

Asteroid Vesta and Mysterious Equatorial Grooves - from Dawn Orbiter
This full view of the giant asteroid Vesta was taken by NASA’s Dawn spacecraft on July 24, 2011, at a distance of 3,200 miles (5,200 kilometers). This view shows impact craters of various sizes and mysterious grooves parallel to the equator. The resolution of this image is about 500 meters per pixel. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

The images in the 3 D video were snapped between July and August 2011 as Dawn completed the final approach to Vesta, achieved orbit in July 2011 and circled overhead during the mission’s initial survey orbit phase at an altitude of about 1,700 miles (2,700 kilometers) in August.

How was the 3 D movie created?

“The Dawn team consists of a bunch of talented people. One of those talented people is Ralf Jaumann, Dawn co-Investigator from the DLR in Berlin,” Prof. Chris Russell, Dawn Principal Investigator, of UCLA, told Universe Today.

“Jaumann and the team behind him have stitched together the mosaics we see and they have made shape models of the surface. They are also skilled communicators and have been heroes in getting the Dawn Image of the Day together. I owe them much thanks and recognition for their efforts.”

“They wanted to make and release to the public an anaglyph of the rotating Vesta to share with everyone the virtual thrill of flying over this alien world.”

“I hope everyone who follows the progress of Dawn will enjoy this movie as much as I do.”

“It is just amazing to an old-time space explorer as myself that we can now make planetary exploration so accessible to people all over our globe in their own homes and so soon after we have received the images,” Russell told me.

3 D of the ‘Snowman' Crater
This anaglyph image shows the topography of Vesta's three craters, informally named the "Snowman," obtained by the framing camera instrument aboard Dawn on August 6, 2011. The camera has a resolution of about 260 meters per pixel.
Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Dawn is now spiraling down to her lowest mapping orbit known as LAMO (Low Altitude Mapping Orbit), barely 130 miles (210 kilometers) above Vesta’s surface.

“Dawn remains on course and on schedule to begin its scientific observations in LAMO on December 12,” says Dr. Marc Rayman, Dawn’s Chief Engineer from the Jet Propulsion Lab (JPL), Pasadena, Calif.

“The focus of LAMO investigations will be on making a census of the atomic constituents with its gamma ray and neutron sensors and on mapping the gravity field in order to determine the interior structure of this protoplanet.”

“Today, Dawn is at about 245 km altitude,” Rayman told Universe Today.

The 3 D video is narrated by Carol Raymond, Dawn’s deputy principal investigator at JPL.

“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”.

“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.”

3 D Image of Vesta's South Polar Region
This anaglyph image of the south polar region was taken on July 9, 2011 by the framing camera instrument aboard NASA's Dawn spacecraft. Each pixel in this image corresponds to roughly 2.2 miles (3.5 kilometers). The anaglyph image shows the rough topography in the south polar area, the large mountain, impact craters, grooves, and steep scarps in three dimensions.
Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Read continuing features about Dawn by Ken Kremer starting here:

NASA Planetary Science Trio Honored as ‘Best of What’s New’ in 2011- Curiosity/Dawn/MESSENGER
Dawn Discovers Surprise 2nd Giant South Pole Impact Basin at Strikingly Dichotomous Vesta
Amazing New View of the Mt. Everest of Vesta
Dramatic 3 D Imagery Showcases Vesta’s Pockmarked, Mountainous and Groovy Terrain
Rheasilvia – Super Mysterious South Pole Basin at Vesta
Space Spectacular — Rotation Movies of Vesta
3 D Alien Snowman Graces Vesta
NASA Unveils Thrilling First Full Frame Images of Vesta from Dawn
Dawn Spirals Down Closer to Vesta’s South Pole Impact Basin
First Ever Vesta Vistas from Orbit – in 2D and 3D
Dawn Exceeds Wildest Expectations as First Ever Spacecraft to Orbit a Protoplanet – Vesta

NASA Planetary Science Trio Honored as ‘Best of What’s New’ in 2011- Curiosity/Dawn/MESSENGER

Popular Science magazine names NASA’s Mars Science Laboratory, Dawn and MESSENGER missions as ‘Best of What’s New’ in innovation in 2011. Artist concept shows mosaic of MESSENGER, Mars Science Laboratory and Dawn missions. Credit: NASA/JPL-Caltech

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A trio of NASA’s Planetary Science mission’s – Mars Science Laboratory (MSL), Dawn and MESSENGER – has been honored by Popular Science magazine and selected as ‘Best of What’s New’ in innovation in 2011 in the aviation and space category.

The Curiosity Mars Science Laboratory was just launched to the Red Planet on Saturday, Nov. 26 and will search for signs of life while traversing around layered terrain at Gale Crater. Dawn just arrived in orbit around Asteroid Vesta in July 2011. MESSENGER achieved orbit around Planet Mercury in March 2011.

Several of the top mission scientists and engineers provided exclusive comments about the Popular Science recognitions to Universe Today – below.

“Of course we are all very pleased by this selection,” Prof. Chris Russell, Dawn Principal Investigator, of UCLA, told Universe Today.


Dawn is the first mission ever to specifically investigate the main Asteroid Belt between Mars and Jupiter and will orbit both Vesta and Ceres – a feat enabled solely thanks to the revolutionary ion propulsion system.

“At the same time I must admit we are also not humble about it. Dawn is truly an amazing mission. A low cost mission, using NASA’s advanced technology to enormous scientific advantage. It is really, really a great mission,” Russell told me.

Vesta is the second most massive asteroid and Dawn’s discoveries of a surprisingly dichotomous and battered world has vastly exceeded the team’s expectations.

Asteroid Vesta from Dawn - Exquisite Clarity from a formerly Fuzzy Blob
NASA's Dawn spacecraft obtained this image of the giant asteroid Vesta with its framing camera on July 24, 2011. It was taken from a distance of about 3,200 miles (5,200 kilometers). Before Dawn, Vesta was just a fuzzy blob in the most powerful telescopes. Dawn entered orbit around Vesta on July 15, and will spend a year orbiting the body before firing up the ion propulsion system to break orbit and speed to Ceres, the largest Asteroid. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

“Dawn is NASA at its best: ambitious, exciting, innovative, and productive,” Dr. Marc Rayman, Dawn’s Chief Engineer from the Jet Propulsion Lab (JPL), Pasadena, Calif., told Universe Today.

“This interplanetary spaceship is exploring uncharted worlds. I’m delighted Popular Science recognizes what a marvelous undertaking this is.”

JPL manages both Dawn and Mars Science Laboratory for NASA’s Science Mission Directorate in Washington, D.C.

Dawn is an international science mission. The partners include the German Aerospace Center (DLR), the Max Planck Institute for Solar System Research, the Italian Space Agency and the Italian National Astrophysical Institute.

“Very cool!”, John Grotzinger, the Mars Science Laboratory Project Scientist of the California Institute of Technology, told Universe Today.

“MSL packs the most bang for the buck yet sent to Mars.”

Last View of Curiosity Mars Science Laboratory Rover - inside the Cleanroom at KSC.
Curiosity just before Encapsulation for 8 month long interplanetary Martian Journey and touchdown inside Gale Crater. Credit: Ken Kremer

Curiosity is using an unprecedented precision landing system to touch down inside the 154 km (96 miile) wide Gale Crater on Aug. 6, 2012. The crater exhibits exposures of phyllosilicates and other minerals that may have preserved evidence of ancient or extant Martian life and is dominated by a towering mountain.

“10 instruments all aimed at a mountain higher than any in the lower 48 states, whose stratigraphic layering records the major breakpoints in the history of Mars’ environments over likely hundreds of millions of years, including those that may have been habitable for life.”

“It’s like a trip down the Grand Canyon 150 years ago, with the same sense of adventure, but with a lot of high tech equipment,” Grotzinger told me.

MSL also has an international team of over 250 science investigators and instruments spread across the US, Europe and Russia.

Curiosity Mars Science Laboratory rover soars to Mars atop an Atlas V rocket on Nov. 26 at 10:02 a.m. EST from Cape Canaveral, Florida. Credit: Ken Kremer

MESSENGER is the first probe to orbit Mercury and the one year primary mission was recently extended by NASA.

Sean Solomon, of the Carnegie Institution of Washington, leads the MESSENGER mission as principal investigator. The Johns Hopkins University Applied Physics Laboratory built and operates the MESSENGER spacecraft for NASA.

“Planetary has 3 missions there… Dawn, MESSENGER, and MSL,” Jim Green proudly said to Universe Today regarding the Popular Science magazine awards. Green is the director, Planetary Science Division, NASA Headquarters, Washington

“Three out of 10 [awards] is a tremendous recognition of the fact that each one of our planetary missions goes to a different environment and takes on new and unique measurements providing us new discoveries and constantly changes how we view nature, ourselves, and our place in the universe.”

The First Solar Day
After its first Mercury solar day (176 Earth days) in orbit, MESSENGER has nearly completed two of its main global imaging campaigns: a monochrome map at 250 m/pixel and an eight-color, 1-km/pixel color map. Apart from small gaps, which will be filled in during the next solar day, these global maps now provide uniform lighting conditions ideal for assessing the form of Mercury’s surface features as well as the color and compositional variations across the planet. The orthographic views seen here, centered at 75° E longitude, are each mosaics of thousands of individual images. At right, images taken through the wide-angle camera filters at 1000, 750, and 430 nm wavelength are displayed in red, green, and blue, respectively.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Read more about the Popular Science citations and awards here
.
Read continuing features about Curiosity, Dawn and MESSENGER by Ken Kremer starting here:

Curiosity Mars Rover Launch Gallery – Photos and Videos
Curiosity Majestically Blasts off on ‘Mars Trek’ to ascertain ‘Are We Alone?
Dawn Discovers Surprise 2nd Giant South Pole Impact Basin at Strikingly Dichotomous Vesta
Amazing New View of the Mt. Everest of Vesta
MESSENGER Unveiling Mercurys Hidden Secrets

Dawn Discovers Surprise 2nd Giant South Pole Impact Basin at Strikingly Dichotomous Vesta

Southern Hemisphere of Vesta; Rheasilvia and Older Basin. Colorized shaded-relief map showing identification of older 375-kilometer-wide impact basin beneath and overlapping with the more recent Rheasilvia impact structure at asteroid Vesta’s South Pole. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

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Scientists leading NASA’s Dawn mission have discovered a 2nd giant impact basin at the south pole of the giant asteroid Vesta, which has been unveiled as a surprisingly “dichotomous” and alien world. Furthermore, the cosmic collisions that produced these two basins shuddered through the interior and created vast Vestan troughs, a Dawn scientist told Universe Today.

The newly discovered impact basin, nicknamed ‘Older Basin’, is actually significantly older in age compared to the initially discovered South Pole basin feature named ‘Rheasilvia’ – perhaps by more than a billion years. And that is just one of the many unexplained mysteries yet to be reconciled by the team as they begin to sift through the millions of bits of new data streaming back daily to Earth.

Scientists speculate that ‘Older Basin’ is on the order of 3.8 Billion years old, whereas ‘Rheasilvia’ might be as young as about 2.5 Billion years, but those are just tentative estimates at this time and subject to change. Measurements so far indicate Rheasilvia is composed of basaltic material.

Shaded-relief topographic map of Vesta southern hemisphere showing two large impact basins - Rheasilvia and Older Basin.
Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

“We found many surprising things at Vesta, which is quite unique and the results have exceeded our expectations”, said Dr. Carol Raymond, Dawn deputy principal investigator, of NASA’s Jet Propulsion Laboratory, Pasadena, Calif.

Researchers presented the latest findings from Dawn’s initial science mapping orbit at a news briefing at the annual meeting of the Geological Society of America in Minneapolis, Minn., on Oct. 13.

The team considers Vesta to be the smallest terrestrial planet.

Since achieving orbit in July, Dawn’s Framing Cameras (FC) have imaged most of Vesta at about 250 meter resolution and the Visible and Infrared mapping spectrometer(VIR) at about 700 meter resolution. The measurements were collected at the survey orbit altitude of 2700 km. Before Dawn, Vesta was just a fuzzy blob in humankind’s most powerful telescopes.

Vesta from Hubble (top) as a fuzzy blob and from Dawn in orbit (bottom) in crystal clear high resolution.
Credit: NASA/JPL-Caltech/ UCLA/MPS/DLR/IDA

“There is a global dichotomy on Vesta and a fundamental difference between the northern and southern hemispheres”, said Raymond. “The northern hemisphere is older and heavily cratered in contrast to the brighter southern hemisphere where the texture is more smooth and there are lots of sets of grooves. There is a massive mountain at the South Pole. One of the more surprising aspects is the set of deep equatorial troughs.”

“There is also a tremendous and surprising diversity of surface color and morphology. The south is consistent with basaltic lithology and the north with impacts. We are trying to make sense of the data and will integrate that with the high resolution observations we are now collecting.”

Indeed Vesta’s completely unique and striking dichotomy can be directly traced back to the basins which were formed by ancient cataclysmic impacts resulting in shockwaves that fundamentally altered the surface and caused the formation of the long troughs that ring Vesta at numerous latitudes.

“The troughs extend across 240 degrees of longitude,” said Debra Buczkowski, Dawn participating scientist, of the Applied Physics Laboratory at Johns Hopkins University, Laurel, Md. “Their formation can be tied back to the two basins at the South Pole.”

Asteroid Vesta and Equatorial Grooves
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. This view of Vesta shows impact craters of various sizes and grooves parallel to the equator. The resolution of this image is about 500 meters per pixel. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

In an exclusive follow up interview with Universe Today, Raymond said “We believe that the troughs formed as a direct result of the impacts,” said “The two sets of troughs are associated with the two large basins [Rheasilvia and Older Basin].”

“The key piece of evidence presented was that the set of troughs in the northern hemisphere, that look older (more degraded) are circumferential to the older impact basin,” Raymond told me.

“The equatorial set are circumferential to Rheasilvia. That Rheasilvia’s age appears in places to be much younger is at odds with the age of the equatorial troughs. An explanation for that could be resurfacing by younger mass wasting features (landslides, slumps). We will be working on clarifying all these relationships in the coming months with the higher resolution HAMO (High Altitude Mapping Orbit) data.”

Dawn has gradually spiraled down closer to Vesta using her exotic ion thrusters and began the HAMO mapping campaign on Sept. 29.

Surface features are dated by crater counting methodology.

“Preliminary crater counting age dates for the equatorial trough region yields a very old age (3.8 Billion years). So there is a discrepancy between the apparent younger age for the Rheasilvia basin and the old age for the troughs. These could be reconciled if Rheasilvia is also 3.8 Billion years old but the surface has been modified by slumping or other processes,” Raymond elaborated.

Time will tell as further data is analyzed.

Dawn launch on September 27, 2007 by a Delta II Heavy rocket from Cape Canaveral Air Force Station, Florida. Credit: Ken Kremer

“Vesta is full of surprises, no more so than at the South Pole,” said Paul Schenk at the GSA briefing. Schenk is a Dawn participating scientist of the Lunar and Planetary Institute, Houston, Texas.

The ‘Rheasilvia’ basin was initially discovered in images of Vesta taken a decade ago by the Hubble Space Telescope which revealed it as a gaping hole in the southern hemisphere. But it wasn’t until Dawn entered orbit on July 16, 2011 after a nearly four year interplanetary journey that Earthlings got their first close up look at the mysterious polar feature and can now scrutinize it in detail to elucidate its true nature.

“The South Pole [Rheasilvia] basin is a roughly circular, impact structure and a deep depression dominated by a large central mound,” said Schenk. “It shows sharp scarps, smooth areas, landslide deposits, debris flows. It’s about 475 km in diameter and one of the deepest (ca. 20 -25 km) impact craters in the solar system.”

The central peak is an enormous mountain, about 22 km high and 180 km across- one of the biggest in the solar system. “It’s comparable in some ways to Olympus Mons on Mars,” Schenk stated.

“We were quite surprised to see a second basin in the mapping data outside of Rheasilvia. This was unexpected. It’s called ‘Older Basin’ for now.”

‘Older Basin’ is about 375 km in diameter. They overlap at the place where Rheasilvia has a missing rim.

“These basins are interesting because we believe Vesta is the source of a large number of meteorites, the HED meteorites that have a spread of ages,” Schenk explained.

Images showing key components of Rheasilvia impact basin on Vesta in high resolution ,referred to Shaded-relief topographic map. Credit: NASA/JPL-Caltech/ UCLA/MPS/DLR/IDA

Multiple large impacts over time may explain the source of the HED (Howardite, Eucrite and Diogenite) meteorites.

“We did expect large impacts on Vesta, likely associated with the late heavy bombardment recognized in the lunar impact record,” Raymond told Universe Today. “The surprising element is that the two apparently largest impacts – keeping in mind that other larger impact basins may be lurking under the regolith – are overlapping.”

Dawn’s VIR spectrometer has detected pyroxene bands covering Vesta’s surface, which is indicative of typical basaltic material, said Federico Tosi, a VIR team member of the Italian Space Agency, Rome. “Vesta has diverse rock types on its surface.”

“VIR measured surface temperatures from 220K to 270 K at the 5 micron wavelength. The illuminated areas are warmer.”

So far there is no clear indication of olivine which would be a marker for seeing Vesta’s mantle, Tossi elaborated.

The VIR spectrometer combines images, spectral information and temperature that will allow researchers to evaluate the nature, composition and evolutionary forces that shaped Vesta’s surface.

The team is absolutely thrilled to see a complicated geologic record that’s been preserved for study with lots of apparent surface layering and surprisingly strong and complex structural features with a large range of color and brightness.

Stay tuned for a year of Vestan delights !

Asteroid Vesta from Dawn
South Pole Rheasilvia basin is at lower right. NASA's Dawn spacecraft obtained this image of the giant asteroid Vesta with its framing camera on July 24, 2011 from a distance of about 3,200 miles (5,200 kilometers). Dawn entered orbit around Vesta on July 16, and will spend a year orbiting the body.
Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Read Ken’s continuing features about Dawn and Vesta starting here:
Amazing New View of the Mt. Everest of Vesta
Dramatic 3 D Imagery Showcases Vesta’s Pockmarked, Mountainous and Groovy Terrain
Rheasilvia – Super Mysterious South Pole Basin at Vesta
Space Spectacular — Rotation Movies of Vesta
3 D Alien Snowman Graces Vesta
NASA Unveils Thrilling First Full Frame Images of Vesta from Dawn
Dawn Spirals Down Closer to Vesta’s South Pole Impact Basin
First Ever Vesta Vistas from Orbit – in 2D and 3D
Dawn Exceeds Wildest Expectations as First Ever Spacecraft to Orbit a Protoplanet – Vesta