Orpington Astronomical Society

Astronomy => In the Media... => Topic started by: Rick on Jul 04, 2007, 15:50:04

Title: NASA's Dawn mission to the asteroids
Post by: Rick on Jul 04, 2007, 15:50:04
Solar-powered ion drive asteroid probe set for launch

NASA has confirmed that the "Dawn" space probe to the asteroid belt will indeed launch on Saturday, ending speculation that the mission might be delayed.

After launching, Dawn will spend four years in transit to the asteroids, circling the Sun twice and gaining a "gravity assist" on the way by making a close approach to Mars.

In 2011, Dawn will go into orbit around Vesta, one of the larger rock-like asteroids in the Belt.

More: http://www.theregister.co.uk/2007/07/04/solar_powered_spaceship_is_go/
Title: Re: Solar-powered ion drive asteroid probe set for launch
Post by: Rick on Jul 10, 2007, 16:25:20
Dawn, NASA's mission to the asteroids, has been postponed again - this time until September. Mission managers had hoped to launch on Monday, but the final decision to delay was taken on Saturday.

More: http://www.theregister.co.uk/2007/07/09/dawn_postponed/
Title: NASA's Dawn Collects a Bounty of Beauty from Vesta
Post by: Rick on Sep 17, 2011, 09:36:47
NASA's Dawn Collects a Bounty of Beauty from Vesta

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

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

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

More: http://www.jpl.nasa.gov/news/news.cfm?release=2011-293
Title: NASA Dawn Mission Reveals Secrets of Large Asteroid
Post by: Rick on May 13, 2012, 07:58:57
NASA Dawn Mission Reveals Secrets of Large Asteroid

NASA's Dawn spacecraft has provided researchers with the first orbital analysis of the giant asteroid Vesta, yielding new insights into its creation and kinship with terrestrial planets and Earth's moon.

Vesta now has been revealed as a special fossil of the early solar system with a more varied, diverse surface than originally thought. Scientists have confirmed a variety of ways in which Vesta more closely resembles a small planet or Earth's moon than another asteroid. Results appear in today's edition of the journal Science.

More: http://www.jpl.nasa.gov/news/news.cfm?release=2012-132
Title: Re: NASA's Dawn mission to the asteroids
Post by: mickw on May 14, 2012, 07:58:31
Virtual flyover movie -

http://apod.nasa.gov/apod/ap120514.html (http://apod.nasa.gov/apod/ap120514.html)
 
Title: Dawn Journal - June 30, 2012
Post by: Rick on Jul 06, 2012, 10:37:11
Dawn Journal - June 30, 2012

Having successfully completed its orbital raising maneuvers to ascend to its second high-altitude mapping orbit (HAMO2), Dawn looks down from about 680 kilometers (420 miles). This is the same height from which it mapped Vesta at the end of September and October 2011. The lifeless rocky landscape has not changed since then, but its appearance to the spacecraft's sensors has. The first high-altitude mapping orbit (HAMO1) was conducted shortly after southern hemisphere summer began on Vesta, so the sun was well south of the equator. That left the high northern latitudes in the deep darkness of winter night. With its slower progression around the sun than Earth, seasons on Vesta last correspondingly longer. Thanks to Dawn's capability to linger in orbit, rather than simply conduct a brief reconnaissance as it speeds by on its way to its next destination, the probe now can examine the surface with different lighting.

More: http://dawn.jpl.nasa.gov/mission/journal_06_30_12.asp
Title: Re: NASA's Dawn mission to the asteroids
Post by: Rick on Jul 29, 2012, 09:19:09
Dawn has completed the final intensive phase of its extraordinary exploration of Vesta, and it has now begun its gradual departure. Propelled by its uniquely efficient ion propulsion system, the probe is spiraling ever higher, reversing the winding path it followed into orbit last year.

More: http://dawn.jpl.nasa.gov/mission/journal_07_25_12.asp
Title: Dawn has Departed the Giant Asteroid Vesta
Post by: Rick on Sep 06, 2012, 08:49:22
Dawn has Departed the Giant Asteroid Vesta

Mission controllers received confirmation today that NASA's Dawn spacecraft has escaped from the gentle gravitational grip of the giant asteroid Vesta. Dawn is now officially on its way to its second destination, the dwarf planet Ceres.

Dawn departed from Vesta at about 11:26 p.m. PDT on Sept. 4 (2:26 a.m. EDT on Sept. 5). Communications from the spacecraft via NASA's Deep Space Network confirmed the departure and that the spacecraft is now traveling toward Ceres.

More: http://www.jpl.nasa.gov/news/news.php?release=2012-277
and: http://dawn.jpl.nasa.gov/mission/journal_09_05_12.asp
Title: Vesta in Dawn's Rear View Mirror
Post by: Rick on Sep 12, 2012, 08:58:06
Vesta in Dawn's Rear View Mirror

NASA's Dawn mission is releasing two parting views of the giant asteroid Vesta, using images that were among the last taken by the spacecraft as it departed its companion for the last year.

The first set of images is a color-coded relief map of Vesta's northern hemisphere, from the pole to the equator. It incorporates images taken just as Dawn began to creep over the high northern latitudes, which were dark when Dawn arrived in July 2011. The other image is a black-and-white mosaic that shows a full view of the giant asteroid, created by synthesizing some of Dawn's best images.

More: http://www.jpl.nasa.gov/news/news.php?release=2012-284
Title: Vesta Up Close: What the Dawn Probe Revealed
Post by: mickw on Oct 28, 2012, 08:17:02
Out between Mars and Jupiter lies a rubble of planets that never quite formed. Although the asteroids date to the birth of our solar system, our closest looks at them have been glimpses from spacecraft whizzing by en route to the glamorous outer solar system.

That changed last July, when NASA's Dawn probe slipped into orbit around Vesta, the asteroid belt’s second most massive member.

More:   Vesta (http://www.space.com/18246-asteroid-vesta-dawn-revelations.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+spaceheadlines+%28SPACE.com+Headline+Feed%29)
Title: Dawn Sees 'Young' Surface on Giant Asteroid
Post by: Rick on Nov 01, 2012, 08:37:36
Dawn Sees 'Young' Surface on Giant Asteroid

Like a Hollywood starlet constantly retouching her makeup, the giant asteroid Vesta is constantly stirring its outermost layer to present a young face. Data from NASA's Dawn mission show that a form of weathering that occurs on the moon and other airless bodies we've visited in the inner solar system does not alter Vesta's outermost layer in the same way. Carbon-rich asteroids have also been splattering dark material on Vesta's surface over a long span of the body's history. The results are described in two papers released today in the journal Nature.

"Dawn's data allow us to decipher how Vesta records fundamental processes that have also affected Earth and other solar system bodies," said Carol Raymond, Dawn deputy principal investigator at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "No object in our solar system is an island. Throughout solar system history, materials have exchanged and interacted."

More: http://www.jpl.nasa.gov/news/news.php?release=2012-342
Title: Dawn Reality-Checks Telescope Studies of Asteroids
Post by: Rick on Sep 27, 2013, 23:30:05
Dawn Reality-Checks Telescope Studies of Asteroids

Tantalized by images from NASA's Hubble Space Telescope and ground-based data, scientists thought the giant asteroid Vesta deserved a closer look. They got a chance to do that in 2011 and 2012, when NASA's Dawn spacecraft orbited the giant asteroid, and they were able to check earlier conclusions. A new study involving Dawn's observations during that time period demonstrates how this relationship works with Hubble and ground-based telescopes to clarify our understanding of a solar system object.

"Since the vast majority of asteroids can only be studied remotely by ground-based and space-based facilities, confirming the accuracy of such observations using in-situ measurements is important to our exploration of the solar system," said Vishnu Reddy, the lead author of a paper published recently in the journal Icarus. Reddy is based at the Planetary Science Institute in Tucson, Ariz., and the Max Planck Institute for Solar System Research in Katlenburg-Lindau, Germany.

In the paper, Reddy and other members of Dawn's framing camera team describe how up-close observations of Vesta have confirmed and provided new insights into more than 200 years of Earth-based observations.

More: http://www.jpl.nasa.gov/news/news.php?release=2013-293
Title: It's Complicated: Dawn Spurs Rewrite of Vesta's Story
Post by: Rick on Nov 07, 2013, 14:00:22
It's Complicated: Dawn Spurs Rewrite of Vesta's Story

Just when scientists thought they had a tidy theory for how the giant asteroid Vesta formed, a new paper from NASA's Dawn mission suggests the history is more complicated.

If Vesta's formation had followed the script for the formation of rocky planets like our own, heat from the interior would have created distinct, separated layers of rock (generally, a core, mantle and crust). In that story, the mineral olivine should concentrate in the mantle.

However, as described in a paper in this week's issue of the journal Nature, that's not what Dawn's visible and infrared mapping spectrometer (VIR) instrument found. The observations of the huge craters in Vesta's southern hemisphere that exposed the lower crust and should have excavated the mantle did not find evidence of olivine there. Scientists instead found clear signatures of olivine in the surface material in the northern hemisphere.

More: http://www.jpl.nasa.gov/news/news.php?release=2013-321
Title: NASA's Dawn Fills out its Ceres Dance Card
Post by: Rick on Dec 04, 2013, 07:51:30
NASA's Dawn Fills out its Ceres Dance Card

It's going to be a ball when NASA's Dawn spacecraft finally arrives at the dwarf planet Ceres, and mission managers have now inked in the schedule on Dawn's dance card.

Dawn has been cruising toward Ceres, the largest object in the main asteroid belt between Mars and Jupiter, since September 2012. That's when it departed from its first dance partner, Vesta.

Ceres presents an icy -- possibly watery -- counterpoint to the dry Vesta, where Dawn spent almost 14 months. Vesta and Ceres are two of the largest surviving protoplanets -- bodies that almost became planets -- and will give scientists clues about the planet-forming conditions at the dawn of our solar system.

When Dawn enters orbit around Ceres, it will be the first spacecraft to see a dwarf planet up-close and the first spacecraft to orbit two solar system destinations beyond Earth.

More: http://www.jpl.nasa.gov/news/news.php?release=2013-347
Also: http://dawn.jpl.nasa.gov/mission/journal_11_30_13.asp
Title: An update on Dawn's mission to Ceres
Post by: Rick on Sep 02, 2014, 08:56:32
An update on Dawn's mission to Ceres

Dawn draws ever closer to the mysterious Ceres, the largest body between the sun and Pluto not yet visited by a probe from Earth. The spacecraft is continuing to climb outward from the sun atop a blue-green beam of xenon ions from its uniquely efficient ion propulsion system. The constant, gentle thrust is reshaping its solar orbit so that by March 2015, it will arrive at the first dwarf planet ever discovered. Once in orbit, it will undertake an ambitious exploration of the exotic world of ice and rock that has been glimpsed only from afar for more than two centuries.

An important characteristic of this interplanetary expedition is that Dawn can linger at its destinations, conducting extensive observations. Since December, we have presented overviews of all the phases of the mission at Ceres save one. (In addition, questions posted by readers each month, occasionally combined with an answer, have helped elucidate some of the interesting features of the mission.) We have described how Dawn will approach its gargantuan new home (with an equatorial diameter of more than 600 miles, or 975 kilometers) and slip into orbit with the elegance of a celestial dancer. The spacecraft will unveil the previously unseen sights with its suite of sophisticated sensors from progressively lower altitude orbits, starting at 8,400 miles (13,500 kilometers), then from survey orbit at 2,730 miles (4,400 kilometers), and then from the misleadingly named high altitude mapping orbit (HAMO) only 910 miles (1,470 kilometers) away. To travel from one orbit to another, it will use its extraordinary ion propulsion system to spiral lower and lower and lower. This month, we look at the final phase of the long mission, as Dawn dives down to the low altitude mapping orbit (LAMO) at 230 miles (375 kilometers). We will also consider what future awaits our intrepid adventurer after it has accomplished the daring plans at Ceres.

More: http://dawnblog.jpl.nasa.gov/2014/08/31/dawn-journal-august-31/
Title: Re: An update on Dawn's mission to Ceres
Post by: Rick on Sep 29, 2014, 08:56:32
An update on Dawn's mission to Ceres

On the seventh anniversary of embarking upon its extraordinary extraterrestrial expedition, the Dawn spacecraft is far from the planet where its journey began. While Earth has completed its repetitive loops around the sun seven times, its ambassador to the cosmos has had a much more varied itinerary. On most of its anniversaries, including this one, it reshapes its orbit around the sun, aiming for some of the last uncharted worlds in the inner solar system. (It also zipped past the oft-visited Mars, robbing the red planet of some of its orbital energy to help fling the spacecraft on to the more distant main asteroid belt.) It spent its fourth anniversary exploring the giant protoplanet Vesta, the second most massive object in the asteroid belt, revealing a fascinating, complex, alien place more akin to Earth and the other terrestrial planets than to typical asteroids. This anniversary is the last it will spend sailing on the celestial seas. By its eighth, it will be at its new, permanent home, dwarf planet Ceres.

More: http://dawnblog.jpl.nasa.gov/2014/09/27/dawn-journal-september-27/
Title: Re: NASA's Dawn mission to the asteroids
Post by: Rick on Nov 15, 2014, 09:54:29
Dawn Journal | October 31

Farther from Earth and from the sun than it has ever been, Dawn is on course and on schedule for its March 2015 arrival at Ceres, an enigmatic world of rock and ice. To slip gracefully into orbit around the dwarf planet, the spacecraft has been using its uniquely capable ion propulsion system to reshape its heliocentric orbit so that it matches Ceres’ orbit. Since departing the giant protoplanet Vesta in Sep. 2012, the stalwart ship has accomplished 99.46 percent of the planned ion thrusting.

What matters most for this daring mission is its ambitious exploration of two uncharted worlds (previews  of the Ceres plan were presented from December 2013 to August 2014), but this month and next, we will consider that 0.54 percent of the thrusting Dawn did not accomplish.

More: http://dawnblog.jpl.nasa.gov/2014/10/31/dawn-journal-october-31/
Title: Geologic Maps of Vesta from NASA's Dawn Mission Published
Post by: Rick on Nov 18, 2014, 23:19:42
Geologic Maps of Vesta from NASA's Dawn Mission Published

mages from NASA's Dawn Mission have been used to create a series of high-resolution geological maps of the large asteroid Vesta, revealing the variety of surface features in unprecedented detail. These maps are included with a series of 11 scientific papers published this week in a special issue of the journal Icarus.

Geological mapping is a technique used to derive the geologic history of a planetary object from detailed analysis of surface morphology, topography, color and brightness information. A team of 14 scientists mapped the surface of Vesta using Dawn spacecraft data, led by three NASA-funded participating scientists: David A. Williams of Arizona State University, Tempe; R. Aileen Yingst of the Planetary Science Institute, Tucson, Arizona; and W. Brent Garry of the NASA Goddard Spaceflight Center, Greenbelt, Maryland.

"The geologic mapping campaign at Vesta took about two-and-a-half years to complete, and the resulting maps enabled us to recognize a geologic timescale of Vesta for comparison to other planets," said Williams.

More: http://www.jpl.nasa.gov/news/news.php?feature=4381
Title: Dawn Snaps Its Best-Yet Image of Dwarf Planet Ceres
Post by: Rick on Dec 06, 2014, 09:10:29
Dawn Snaps Its Best-Yet Image of Dwarf Planet Ceres

The Dawn spacecraft has delivered a glimpse of Ceres, the largest body in the main asteroid belt, in a new image taken 740,000 miles (1.2 million kilometers) from the dwarf planet. This is Dawn's best image yet of Ceres as the spacecraft makes its way toward this unexplored world.

"Now, finally, we have a spacecraft on the verge of unveiling this mysterious, alien world. Soon it will reveal myriad secrets Ceres has held since the dawn of the solar system," said Marc Rayman, of NASA's Jet Propulsion Laboratory in Pasadena, California, chief engineer and mission director of the Dawn mission.

Dawn will be captured into Ceres' orbit in March, marking the first visit to a dwarf planet by a spacecraft. To date, the best images of Ceres come from the Hubble Space Telescope. In early 2015, however, Dawn will begin delivering images at much higher resolution.

More: http://www.jpl.nasa.gov/news/news.php?feature=4395
Title: Dawn Delivers New Image of Ceres
Post by: Rick on Jan 20, 2015, 00:06:46
Dawn Delivers New Image of Ceres

As NASA's Dawn spacecraft closes in on Ceres, new images show the dwarf planet at 27 pixels across, about three times better than the calibration images taken in early December. These are the first in a series of images that will be taken for navigation purposes during the approach to Ceres.

Over the next several weeks, Dawn will deliver increasingly better and better images of the dwarf planet, leading up to the spacecraft's capture into orbit around Ceres on March 6. The images will continue to improve as the spacecraft spirals closer to the surface during its 16-month study of the dwarf planet.

"We know so much about the solar system and yet so little about dwarf planet Ceres. Now, Dawn is ready to change that," said Marc Rayman, Dawn's chief engineer and mission director, based at NASA's Jet Propulsion Laboratory in Pasadena, California.

The best images of Ceres so far were taken by NASA's Hubble Space Telescope in 2003 and 2004. This most recent images from Dawn, taken January 13, 2015, at about 80 percent of Hubble resolution, are not quite as sharp. But Dawn's images will surpass Hubble's resolution at the next imaging opportunity, which will be at the end of January.

More: http://www.jpl.nasa.gov/news/news.php?release=2015-023
Title: Re: Dawn Delivers New Image of Ceres
Post by: Rick on Jan 20, 2015, 08:45:54
...and an APOD: http://apod.nasa.gov/apod/ap150120.html
Title: Re: Dawn Delivers New Image of Ceres
Post by: Rick on Jan 21, 2015, 18:37:49
...and http://xkcd.com/1476/
Title: Bright Spot on Dwarf Planet Ceres: What Is It?
Post by: Kenny on Jan 24, 2015, 00:19:52
A strange, flickering white blotch found on the dwarf planet Ceres by a NASA spacecraft has scientists scratching their heads.

The white spot on Ceres in a series of new photos taken on Jan. 13 by NASA's Dawn spacecraft, which is rapidly approaching the round dwarf planet in the asteroid belt between the orbits of Mars and Jupiter. But when the initial photo release on Monday (Jan. 19), the Dawn scientists gave no indication of what the white dot might be.

http://m.space.com/28336-mysterious-white-spot-on-ceres.html
Title: Re: NASA's Dawn mission to the asteroids
Post by: Mike on Jan 24, 2015, 09:33:04
My guess is a crater filled with ice.
Title: Gullies on Vesta Suggest Past Water-Mobilized Flows
Post by: Rick on Jan 25, 2015, 10:29:14
Gullies on Vesta Suggest Past Water-Mobilized Flows

Protoplanet Vesta, visited by NASA's Dawn spacecraft from 2011 to 2013, was once thought to be completely dry, incapable of retaining water because of the low temperatures and pressures at its surface. However, a new study shows evidence that Vesta may have had short-lived flows of water-mobilized material on its surface, based on data from Dawn.

"Nobody expected to find evidence of water on Vesta. The surface is very cold and there is no atmosphere, so any water on the surface evaporates," said Jennifer Scully, postgraduate researcher at the University of California, Los Angeles. "However, Vesta is proving to be a very interesting and complex planetary body."

The study has broad implications for planetary science.

More: http://www.jpl.nasa.gov/news/news.php?feature=4453
Title: Re: NASA's Dawn mission to the asteroids
Post by: Rick on Feb 03, 2015, 08:36:46
Dawn Journal | January 29

Dawn’s unique method of patiently, gradually reshaping its orbit around the sun with its ion propulsion system is nearly at its end. Just as two cars may drive together at high speed and thus travel at low speed relative to each other, Dawn is now close to matching Ceres’ heliocentric orbital motion. Together, they are traveling around the sun at nearly 39,000 mph (almost 64,000 kilometers per hour), or 10.8 miles per second (17.4 kilometers per second). But the spaceship is closing in on the world ahead at the quite modest relative speed of about 250 mph (400 kilometers per hour), much less than is typical for interplanetary spaceflight.

Dawn has begun its approach imaging campaign, and the pictures are wonderfully exciting. This month, we will take a more careful look at the plans for photographing Ceres....

...

Dawn turned to observe Vesta during that approach phase more often than it does on approach to Ceres, and the reason is simple. It has lost two of its four reaction wheels, devices used to help turn or stabilize the craft in the zero-gravity, frictionless conditions of spaceflight. (In full disclosure, the units aren’t actually lost. We know precisely where they are. But given that they stopped functioning, they might as well be elsewhere in the universe; they don’t do Dawn any good.)

...

Dawn is 121,000 miles (195,000 kilometers) from Ceres, or half the average distance between Earth and the moon. It is also 3.63 AU (338 million miles, or 544 million kilometers) from Earth, or 1,390 times as far as the moon and 3.69 times as far as the sun today. Radio signals, traveling at the universal limit of the speed of light, take one hour to make the round trip.

Read the whole Dawn Journal for January 29th (http://dawnblog.jpl.nasa.gov/2015/01/29/dawn-journal-january-29/).
Title: Dawn Gets Closer Views of Ceres
Post by: Rick on Feb 06, 2015, 08:50:38
Dawn Gets Closer Views of Ceres

NASA's Dawn spacecraft, on approach to dwarf planet Ceres, has acquired its latest and closest-yet snapshot of this mysterious world. The image of Ceres, taken on Feb. 4, 2015, from a distance of about 90,000 miles (145,000 kilometers), is available at:

http://www.jpl.nasa.gov/spaceimages/details.php?id=pia19174
http://www.jpl.nasa.gov/spaceimages/details.php?id=pia19179

At a resolution of 8.5 miles (14 kilometers) per pixel, the pictures represent the sharpest images to date of Ceres.

From: http://www.jpl.nasa.gov/news/news.php?feature=4475
Title: Dawn Captures Sharper Images of Ceres
Post by: Rick on Feb 17, 2015, 23:02:52
Dawn Captures Sharper Images of Ceres

Craters and mysterious bright spots are beginning to pop out in the latest images of Ceres from NASA's Dawn spacecraft. These images, taken Feb. 12 at a distance of 52,000 miles (83,000 kilometers) from the dwarf planet, pose intriguing questions for the science team to explore as the spacecraft nears its destination.

The image is available at:

http://www.jpl.nasa.gov/spaceimages/details.php?id=PIA19056

More: http://www.jpl.nasa.gov/news/news.php?feature=4485
Title: 'Bright Spot' on Ceres Has Dimmer Companion
Post by: Rick on Feb 26, 2015, 10:55:29
'Bright Spot' on Ceres Has Dimmer Companion

Dwarf planet Ceres continues to puzzle scientists as NASA's Dawn spacecraft gets closer to being captured into orbit around the object. The latest images from Dawn, taken nearly 29,000 miles (46,000 kilometers) from Ceres, reveal that a bright spot that stands out in previous images lies close to yet another bright area.

"Ceres' bright spot can now be seen to have a companion of lesser brightness, but apparently in the same basin. This may be pointing to a volcano-like origin of the spots, but we will have to wait for better resolution before we can make such geologic interpretations," said Chris Russell, principal investigator for the Dawn mission, based at the University of California, Los Angeles.

Using its ion propulsion system, Dawn will enter orbit around Ceres on March 6. As scientists receive better and better views of the dwarf planet over the next 16 months, they hope to gain a deeper understanding of its origin and evolution by studying its surface. The intriguing bright spots and other interesting features of this captivating world will come into sharper focus.

More: http://www.jpl.nasa.gov/news/news.php?feature=4491

The Dawn spacecraft is performing flawlessly as it conducts the first exploration of the first dwarf planet. Each new picture of Ceres reveals exciting and surprising new details about a fascinating and enigmatic orb that has been glimpsed only as a smudge of light for more than two centuries. And yet as that fuzzy little blob comes into sharper focus, it seems to grow only more perplexing.

Dawn is showing us exotic scenery on a world that dates back to the dawn of the solar system, more than 4.5 billion years ago. Craters large and small remind us that Ceres lives in the rough and tumble environment of the main asteroid belt between Mars and Jupiter, and collectively they will help scientists develop a deeper understanding of the history and nature not only of Ceres itself but also of the solar system.

More: http://dawnblog.jpl.nasa.gov/2015/02/25/dawn-journal-february-25/
Title: NASA Spacecraft Nears Historic Dwarf Planet Arrival
Post by: Rick on Mar 03, 2015, 11:26:25
NASA Spacecraft Nears Historic Dwarf Planet Arrival

NASA's Dawn spacecraft has returned new images captured on approach to its historic orbit insertion at the dwarf planet Ceres. Dawn will be the first mission to successfully visit a dwarf planet when it enters orbit around Ceres on Friday, March 6.

"Dawn is about to make history," said Robert Mase, project manager for the Dawn mission at NASA's Jet Propulsion Laboratory in Pasadena, California. "Our team is ready and eager to find out what Ceres has in store for us."

Recent images show numerous craters and unusual bright spots that scientists believe tell how Ceres, the first object discovered in our solar system's asteroid belt, formed and whether its surface is changing. As the spacecraft spirals into closer and closer orbits around the dwarf planet, researchers will be looking for signs that these strange features are changing, which would suggest current geological activity.

More: http://www.jpl.nasa.gov/news/news.php?feature=4496
Title: NASA Spacecraft Becomes First to Orbit a Dwarf Planet
Post by: Rick on Mar 07, 2015, 08:25:26
NASA Spacecraft Becomes First to Orbit a Dwarf Planet

NASA's Dawn spacecraft has become the first mission to achieve orbit around a dwarf planet. The spacecraft was approximately 38,000 miles (61,000 kilometers) from Ceres when it was captured by the dwarf planet's gravity at about 4:39 a.m. PST (7:39 a.m. EST) Friday.

Mission controllers at NASA's Jet Propulsion Laboratory in Pasadena, California received a signal from the spacecraft at 5:36 a.m. PST (8:36 a.m. EST) that Dawn was healthy and thrusting with its ion engine, the indicator Dawn had entered orbit as planned.

"Since its discovery in 1801, Ceres was known as a planet, then an asteroid and later a dwarf planet," said Marc Rayman, Dawn chief engineer and mission director at JPL. "Now, after a journey of 3.1 billion miles (4.9 billion kilometers) and 7.5 years, Dawn calls Ceres, home."

More: http://www.jpl.nasa.gov/news/news.php?feature=4503
Title: Dawn's complex approach to Ceres
Post by: Rick on Mar 09, 2015, 19:28:43
Dawn's complex approach to Ceres

Since its discovery in 1801, Ceres has been known as a planet, then as an asteroid, and later as a dwarf planet. Now, after a journey of 3.1 billion miles (4.9 billion kilometers) and 7.5 years, Dawn calls it “home.”

Earth’s robotic emissary arrived at about 4:39 a.m. PST today. It will remain in residence at the alien world for the rest of its operational life, and long, long after.

Before we delve into this unprecedented milestone in the exploration of space, let’s recall that even before reaching orbit, Dawn started taking pictures of its new home. Last month we presented the updated schedule for photography. Each activity to acquire images (as well as visible spectra and infrared spectra) has executed smoothly and provided us with exciting and tantalizing new perspectives.

While there are countless questions about Ceres, the most popular now seems to be what the bright spots are. It is impossible not to be mesmerized by what appear to be glowing beacons, shining out across the cosmic seas from the uncharted lands ahead. But the answer hasn’t changed: we don’t know. There are many intriguing speculations, but we need more data, and Dawn will take photos and myriad other measurements as it spirals closer and closer during the year. For now, we simply know too little.

More: http://dawnblog.jpl.nasa.gov/2015/03/06/dawn-journal-march-6/
Title: Other Asteroids Contributed Elusive Olivine to Vesta
Post by: Rick on Mar 19, 2015, 08:35:16
Other Asteroids Contributed Elusive Olivine to Vesta

Olivine should be one of the most abundant minerals on asteroid Vesta, but it remains elusive. Scientists working on NASA’s Dawn mission to Vesta were initially thrilled to find few scattered remains of this enigmatic mineral as evidence for telltale signs of planetary differentiation. However, a new paper in the journal Icarus says that at least some of this olivine might not have come from Vesta, but instead was delivered by other asteroids.
 
“Olivine provides important constraints on how small protoplanets like Vesta form and what we can learn about the formation of terrestrial planets, including Earth, but what we see on Vesta might not be the smoking gun we were looking for,” said Planetary Science Institute researcher Lucille Le Corre, the lead author of the new study.

More: http://www.psi.edu/news/olivinevesta
Title: Getting Down to Science at Ceres
Post by: Rick on May 08, 2015, 08:52:11
Getting Down to Science at Ceres

 Dawn's assignment when it embarked on its extraordinary extraterrestrial expedition in 2007 can be described quite simply: explore the two most massive uncharted worlds in the inner solar system. It conducted a spectacular mission at Vesta, orbiting the giant protoplanet for 14 months in 2011-2012, providing a wonderfully rich and detailed view. Now the sophisticated probe is performing its first intensive investigation of dwarf planet Ceres. Dawn is slowly circling the alien world of rock and ice, far from Earth and far from the sun, executing its complex operations with the prowess it has demonstrated throughout its ambitious journey.

Following an interplanetary trek of 7.5 years and 3.1 billion miles (4.9 billion kilometers), Earth's ambassador arrived in orbit on March 6, answering Ceres' two-century-old celestial invitation. With its advanced ion propulsion system and ace piloting skills, it has maneuvered extensively in orbit. Traveling mostly high over the night side of Ceres, arcing and banking, thrusting and coasting, accelerating and decelerating, climbing and diving, the spaceship flew to its first targeted orbital altitude, which it reached on April 23.

More: http://www.jpl.nasa.gov/blog/2015/4/getting-down-to-science-at-ceres
Title: Ceres Animation Showcases Bright Spots
Post by: Rick on May 12, 2015, 10:09:59
Ceres Animation Showcases Bright Spots

The mysterious bright spots on the dwarf planet Ceres are better resolved in a new sequence of images taken by NASA's Dawn spacecraft on May 3 and 4, 2015. The images were taken from a distance of 8,400 miles (13,600 kilometers). The animation is available at:

http://www.jpl.nasa.gov/spaceimages/details.php?id=pia19547

In this closest-yet view, the brightest spots within a crater in the northern hemisphere are revealed to be composed of many smaller spots. However, their exact nature remains unknown.

"Dawn scientists can now conclude that the intense brightness of these spots is due to the reflection of sunlight by highly reflective material on the surface, possibly ice," said Christopher Russell, principal investigator for the Dawn mission from the University of California, Los Angeles.

More: http://www.jpl.nasa.gov/news/news.php?feature=4582
Title: Ceres Bright Spots Seen Closer Than Ever
Post by: Rick on May 22, 2015, 08:21:32
Ceres Bright Spots Seen Closer Than Ever

NASA's Dawn mission captured a sequence of images, taken for navigation purposes, of dwarf planet Ceres on May 16, 2015. The image showcases the group of the brightest spots on Ceres, which continue to mystify scientists. It was taken from a distance of 4,500 miles (7,200 kilometers) and has a resolution of 2,250 feet (700 meters) per pixel.

"Dawn scientists can now conclude that the intense brightness of these spots is due to the reflection of sunlight by highly reflective material on the surface, possibly ice," Christopher Russell, principal investigator for the Dawn mission from the University of California, Los Angeles, said recently.

More: http://www.jpl.nasa.gov/news/news.php?feature=4594
Title: Dawn Spirals Closer to Ceres, Returns a New View
Post by: Rick on May 29, 2015, 08:22:57
Dawn Spirals Closer to Ceres, Returns a New View

A new view of Ceres, taken by NASA's Dawn spacecraft on May 23, shows finer detail is becoming visible on the dwarf planet. The spacecraft snapped the image at a distance of 3,200 miles (5,100 kilometers) with a resolution of 1,600 feet (480 meters) per pixel. The image is part of a sequence taken for navigational purposes.

Go see it at: http://www.jpl.nasa.gov/news/news.php?feature=4605
Title: Re: NASA's Dawn mission to the asteroids
Post by: Rick on May 30, 2015, 10:57:06
Dawn Journal | May 28, 2015

The first intensive mapping campaign was extremely productive. As the spacecraft circled 8,400 miles (13,600 kilometers) above the alien terrain, one orbit around Ceres took 15 days. During its single revolution, the probe observed its new home on five occasions from April 24 to May 8. When Dawn was flying over the night side (still high enough that it was in sunlight even when the ground below was in darkness), it looked first at the illuminated crescent of the southern hemisphere and later at the northern hemisphere.

When Dawn traveled over the sunlit side, it watched the northern hemisphere, then the equatorial regions, and finally the southern hemisphere as Ceres rotated beneath it each time. One Cerean day, the time it takes the globe to turn once on its axis, is about nine hours, much shorter than the time needed for the spacecraft to loop around its orbit. So it was almost as if Dawn hovered in place, moving only slightly as it peered down, and its instruments could record all of the sights as they paraded by.

More: http://dawnblog.jpl.nasa.gov/2015/05/28/dawn-journal-may-28-2015/
Title: Re: NASA's Dawn mission to the asteroids
Post by: Apophis on May 30, 2015, 14:44:47
Look at http://www.jpl.nasa.gov/spaceimages/images/largesize/PIA19559_hires.jpg (http://www.jpl.nasa.gov/spaceimages/images/largesize/PIA19559_hires.jpg)

If you look at the crater with the white in and go up 2 large craters then 11 o,clock to next large crater it seems to have features in it formed with flowing liquid.

roger

(Edit: Image issues -- Rick)
Title: Bright Spots Shine in Newest Dawn Ceres Images
Post by: Rick on Jun 11, 2015, 11:27:52
Bright Spots Shine in Newest Dawn Ceres Images

New images of dwarf planet Ceres, taken by NASA's Dawn spacecraft, show the cratered surface of this mysterious world in sharper detail than ever before. These are among the first snapshots from Dawn's second mapping orbit, which is 2,700 miles (4,400 kilometers) above Ceres.

The region with the brightest spots is in a crater about 55 miles (90 kilometers) across. The spots consist of many individual bright points of differing sizes, with a central cluster. So far, scientists have found no obvious explanation for their observed locations or brightness levels.

"The bright spots in this configuration make Ceres unique from anything we've seen before in the solar system. The science team is working to understand their source. Reflection from ice is the leading candidate in my mind, but the team continues to consider alternate possibilities, such as salt. With closer views from the new orbit and multiple view angles, we soon will be better able to determine the nature of this enigmatic phenomenon," said Chris Russell, principal investigator for the Dawn mission based at the University of California, Los Angeles.

More: http://www.jpl.nasa.gov/news/news.php?feature=4619
Title: Re: NASA's Dawn mission to the asteroids
Post by: Mike on Jun 12, 2015, 17:19:59
It's interesting that in EVERY picture the spots are super bright white. If it was reflection off liquid I would expect it to be bright only at certain angles. This now make me think it is salts or somethings crystalline that has many facets that will always face the spacecraft.
Title: Ceres Spots Continue to Mystify in Latest Dawn Images
Post by: Rick on Jun 23, 2015, 07:51:40
Ceres Spots Continue to Mystify in Latest Dawn Images

Dawn has been studying the dwarf planet in detail from its second mapping orbit, which is 2,700 miles (4,400 kilometers) above Ceres. A new view of its intriguing bright spots, located in a crater about 55 miles (90 kilometers) across, shows even more small spots in the crater than were previously visible.

At least eight spots can be seen next to the largest bright area, which scientists think is approximately 6 miles (9 kilometers) wide. A highly reflective material is responsible for these spots -- ice and salt are leading possibilities, but scientists are considering other options, too.

More: http://www.jpl.nasa.gov/news/news.php?feature=4633
Title: Re: NASA's Dawn mission to the asteroids
Post by: Rick on Jul 02, 2015, 08:18:03
Dawn Journal | June 29

Dawn is continuing to unveil a Ceres of mysteries at the first dwarf planet discovered. The spacecraft has been extremely productive, returning a wealth of photographs and other scientific measurements to reveal the nature of this exotic alien world of rock and ice. First glimpsed more than 200 years ago as a dot of light among the stars, Ceres is the only dwarf planet between the sun and Neptune.

Dawn has been orbiting Ceres every 3.1 days at an altitude of 2,700 miles (4,400 kilometers). As described last month, the probe aimed its powerful sensors at the strange landscape throughout each long, slow passage over the side of Ceres facing the sun. Meanwhile, Ceres turned on its axis every nine hours, presenting itself to the ambassador from Earth. On the half of each revolution when Dawn was above ground that was cloaked in the darkness of night, it pointed its main antenna to that planet far, far away and radioed its precious findings to eager Earthlings (although the results will be available for others throughout the cosmos as well). Dawn began this second mapping campaign (also known as “survey orbit”) on June 5, and tomorrow it will complete its eighth and final revolution.

The spacecraft made most of its observations by looking straight down at the terrain directly beneath it. During portions of its first, second and fourth orbits, however, Dawn peered at the limb of Ceres against the endless black of space, seeing the sights from a different perspective to gain a better sense of the lay of the land.

Read on... (http://dawnblog.jpl.nasa.gov/2015/06/29/dawn-journal-june-29/)
Title: Re: NASA's Dawn mission to the asteroids
Post by: Mike on Jul 10, 2015, 18:35:20
Here you go, I said it was salts..

Pluto may be the star of the dwarf planet scene for the next few days, but let's not forget about Ceres: We've been salivating over the mysterious white spots on its surface since NASA's Dawn orbiter sent its first photos home. But according to the mission's principle investigator, the crowd favorite theory -- that the spots are made of some kind of water or ice -- is probably about to be debunked.

http://www.washingtonpost.com/news/speaking-of-science/wp/2015/07/10/the-weird-white-spots-on-ceres-might-not-be-ice-after-all

Title: Dawn Maneuvering to Third Science Orbit
Post by: Rick on Jul 21, 2015, 08:25:05
Dawn Maneuvering to Third Science Orbit

NASA's Dawn spacecraft is using its ion propulsion system to descend to its third mapping orbit at Ceres, and all systems are operating well. The spiral maneuvering over the next five weeks will take the spacecraft to an altitude of about 900 miles (less than 1,500 kilometers) above the dwarf planet.

The spacecraft experienced a discrepancy in its expected orientation on June 30, triggering a safe mode. Engineers traced this anomaly to the mechanical gimbal system that swivels ion engine #3 to help control the spacecraft's orientation during ion-thrusting. Dawn has three ion engines and uses only one at a time.

More: http://www.jpl.nasa.gov/news/news.php?feature=4659
Title: New Names and Insights at Ceres
Post by: Rick on Jul 30, 2015, 08:16:24
New Names and Insights at Ceres

Colorful new maps of Ceres, based on data from NASA's Dawn spacecraft, showcase a diverse topography, with height differences between crater bottoms and mountain peaks as great as 9 miles (15 kilometers).

Scientists continue to analyze the latest data from Dawn as the spacecraft makes its way to its third mapping orbit.

"The craters we find on Ceres, in terms of their depth and diameter, are very similar to what we see on Dione and Tethys, two icy satellites of Saturn that are about the same size and density as Ceres. The features are pretty consistent with an ice-rich crust," said Dawn science team member Paul Schenk, a geologist at the Lunar and Planetary Institute, Houston.

More: http://www.jpl.nasa.gov/news/news.php?feature=4669
Title: Re: NASA's Dawn mission to the asteroids
Post by: Rick on Aug 01, 2015, 09:01:00
Flying on a blue-green ray of xenon ions, Dawn is gracefully descending toward dwarf planet Ceres. Even as Dawn prepares for a sumptuous new feast in its next mapping orbit, scientists are continuing to delight in the delicacies Ceres has already served. With a wonderfully rich bounty of pictures and other observations already secured, the explorer is now on its way to an even better vantage point.

More: http://dawnblog.jpl.nasa.gov/2015/07/29/dawn-journal-july-29/
Title: Cruise Over Ceres in New Video
Post by: Rick on Aug 08, 2015, 09:24:47
Cruise Over Ceres in New Video

Striking 3-D detail highlights a towering mountain, the brightest spots and other features on dwarf planet Ceres in a new video from NASA's Dawn mission.

A prominent mountain with bright streaks on its steep slopes is especially fascinating to scientists. The peak's shape has been likened to a cone or a pyramid. It appears to be about 4 miles (6 kilometers) high, with respect to the surface around it, according to the latest estimates. This means the mountain has about the same elevation as Mount McKinley in Denali National Park, Alaska, the highest point in North America.

More: http://www.jpl.nasa.gov/news/news.php?feature=4677
Title: Dawn Sends Sharper Scenes from Ceres
Post by: Rick on Aug 27, 2015, 14:30:47
Dawn Sends Sharper Scenes from Ceres

The closest-yet views of Ceres, delivered by NASA's Dawn spacecraft, show the small world's features in unprecedented detail, including Ceres' tall, conical mountain; crater formation features and narrow, braided fractures.

"Dawn is performing flawlessly in this new orbit as it conducts its ambitious exploration. The spacecraft's view is now three times as sharp as in its previous mapping orbit, revealing exciting new details of this intriguing dwarf planet," said Marc Rayman, Dawn's chief engineer and mission director, based at NASA's Jet Propulsion Laboratory, Pasadena, California.

More: http://www.jpl.nasa.gov/news/news.php?feature=4697
Title: Ceres' Bright Spots Seen in Striking New Detail
Post by: Rick on Sep 11, 2015, 09:21:17
Ceres' Bright Spots Seen in Striking New Detail

The brightest spots on the dwarf planet Ceres gleam with mystery in new views delivered by NASA's Dawn spacecraft. These closest-yet views of Occator crater, with a resolution of 450 feet (140 meters) per pixel, give scientists a deeper perspective on these very unusual features.

The new up-close view of Occator crater from Dawn's current vantage point reveals better-defined shapes of the brightest, central spot and features on the crater floor. Because these spots are so much brighter than the rest of Ceres' surface, the Dawn team combined two different images into a single composite view -- one properly exposed for the bright spots, and one for the surrounding surface.

Scientists also have produced animations that provide a virtual fly-around of the crater, including a colorful topographic map.

More: http://www.jpl.nasa.gov/news/news.php?feature=4714
Title: Dawn Heads Toward Final Orbit
Post by: Rick on Oct 30, 2015, 21:14:11
Dawn Heads Toward Final Orbit

NASA's Dawn spacecraft fired up its ion engine on Friday, Oct. 23, to begin its journey toward its fourth and final science orbit at dwarf planet Ceres. The spacecraft completed two months of observations from an altitude of 915 miles (1,470 kilometers) and transmitted extensive imagery and other data to Earth.

The spacecraft is now on its way to the final orbit of the mission, called the low-altitude mapping orbit. Dawn will spend more than seven weeks descending to this vantage point, which will be less than 235 miles (380 kilometers) from the surface of Ceres. In mid-December, Dawn will begin taking observations from this orbit, including images at a resolution of 120 feet (35 meters) per pixel.

More: http://www.jpl.nasa.gov/news/news.php?feature=4751
Title: Dawn Journal - October 30, 2015
Post by: Rick on Nov 03, 2015, 09:25:08
Dawn Journal - October 30, 2015

Dawn has completed another outstandingly successful campaign to acquire a wealth of pictures and other data in its exploration of dwarf planet Ceres. Exultant residents of distant Earth now have the clearest and most complete view ever of this former planet.

More: http://dawnblog.jpl.nasa.gov/2015/10/30/dawn-journal-october-30/
Title: What smacks into Ceres stays on Ceres
Post by: Rick on Nov 05, 2015, 11:06:54
What smacks into Ceres stays on Ceres

Ceres is the largest object in the asteroid belt and the nearest dwarf planet to Earth. Until the recent arrival of the Dawn spacecraft, all that was known about Ceres came from telescopic observations. The observations showed Ceres to be mysteriously low in density, suggesting it is made either of very porous silicate material, or perhaps contains a large layer of water ice. Observations of its surface were remarkable as well — largely for being unremarkable.

“It’s really bland in the telescopic observations,” said Daly, a Ph.D. student at Brown and the study’s lead author. “It’s like someone took a single color of spray paint and sprayed the whole thing. When we think about what might have caused this homogeneous surface, our thoughts turn to impact processes.”

And to understand impact processes, the researchers turned to NASA’s Vertical Gun Range, a cannon with a 14-foot barrel that can launch projectiles at up to 16,000 miles per hour. For this work, Daly and Schultz wanted to simulate impacts into low-density surfaces that mimic the two broad possibilities for the composition of Ceres’s surface: porous silicate or icy.

More: https://news.brown.edu/articles/2015/10/ceres
Title: Dawn Journal - November 30, 2015
Post by: Rick on Dec 03, 2015, 23:14:22
Dawn Journal - November 30, 2015

An intrepid interplanetary explorer is now powering its way down through the gravity field of a distant alien world. Soaring on a blue-green beam of high-velocity xenon ions, Dawn is making excellent progress as it spirals closer and closer to Ceres, the first dwarf planet discovered. Meanwhile, scientists are progressing in analyzing the tremendous volume of pictures and other data the probe has already sent to Earth.

More: http://dawnblog.jpl.nasa.gov/2015/11/30/dawn-journal-november-30/
Title: New Clues to Ceres' Bright Spots and Origins
Post by: Rick on Dec 10, 2015, 08:51:14
New Clues to Ceres' Bright Spots and Origins

Ceres has more than 130 bright areas, and most of them are associated with impact craters. Study authors, led by Andreas Nathues at Max Planck Institute for Solar System Research, Göttingen, Germany, write that the bright material is consistent with a type of magnesium sulfate called hexahydrite. A different type of magnesium sulfate is familiar on Earth as Epsom salt.

Nathues and colleagues, using images from Dawn's framing camera, suggest that these salt-rich areas were left behind when water-ice sublimated in the past. Impacts from asteroids would have unearthed the mixture of ice and salt, they say.

"The global nature of Ceres' bright spots suggests that this world has a subsurface layer that contains briny water-ice," Nathues said.

More: http://www.jpl.nasa.gov/news/news.php?feature=4785
Title: Ceres: Keeping Well-Guarded Secrets for 215 Years
Post by: Rick on Jan 29, 2016, 09:49:32
Ceres: Keeping Well-Guarded Secrets for 215 Years

New Year's Day, 1801, the dawn of the 19th century, was a historic moment for astronomy, and for a space mission called Dawn more than 200 years later. That night, Giuseppe Piazzi pointed his telescope at the sky and observed a distant object that we now know as Ceres.

Today, NASA's Dawn mission allows us to see Ceres in exquisite detail. From the images Dawn has taken over the past year, we know Ceres is a heavily cratered body with diverse features on its surface that include a tall, cone-shaped mountain and more than 130 reflective patches of material that is likely salt. But on that fateful evening in 1801, Piazzi wasn't sure what he was seeing when he noticed a small, faint light through his telescope.

"When Piazzi discovered Ceres, exploring it was beyond imagination. More than two centuries later, NASA dispatched a machine on a cosmic journey of more than 3 billion miles to reach the distant, mysterious world he glimpsed," said Marc Rayman, mission director and chief engineer for Dawn at NASA's Jet Propulsion Laboratory, Pasadena, California.

More: http://www.jpl.nasa.gov/news/news.php?feature=4824
Title: New Animation Takes a Colorful Flight Over Ceres
Post by: Rick on Feb 04, 2016, 08:21:50
New Animation Takes a Colorful Flight Over Ceres

A colorful new animation shows a simulated flight over the surface of dwarf planet Ceres, based on images from NASA's Dawn spacecraft.

The movie shows Ceres in enhanced color, which helps to highlight subtle differences in the appearance of surface materials. Scientists believe areas with shades of blue contain younger, fresher material, including flows, pits and cracks.

The animated flight over Ceres emphasizes the most prominent craters, such as Occator, and the tall, conical mountain Ahuna Mons. Features on Ceres are named for earthly agricultural spirits, deities and festivals.

More: http://www.jpl.nasa.gov/news/news.php?feature=4836
Title: Dawn's First Year at Ceres: A Mountain Emerges
Post by: Rick on Mar 18, 2016, 09:43:31
Dawn's First Year at Ceres: A Mountain Emerges

One year ago, on March 6, 2015, NASA's Dawn spacecraft slid gently into orbit around Ceres, the largest body in the asteroid belt between Mars and Jupiter.  Since then, the spacecraft has delivered a wealth of images and other data that open an exciting new window to the previously unexplored dwarf planet.

"Ceres has defied our expectations and surprised us in many ways, thanks to a year's worth of data from Dawn. We are hard at work on the mysteries the spacecraft has presented to us," said Carol Raymond, deputy principal investigator for the mission, based at NASA's Jet Propulsion Laboratory, Pasadena, California.

More: http://www.jpl.nasa.gov/news/news.php?feature=5745
Title: Bright Spots and Color Differences Revealed on Ceres
Post by: Rick on Mar 25, 2016, 13:36:55
Bright Spots and Color Differences Revealed on Ceres

Occator Crater, measuring 57 miles (92 kilometers) across and 2.5 miles (4 kilometers) deep, contains the brightest area on Ceres, the dwarf planet that Dawn has explored since early 2015. The latest images, taken from 240 miles (385 kilometers) above the surface of Ceres, reveal a dome in a smooth-walled pit in the bright center of the crater. Numerous linear features and fractures crisscross the top and flanks of this dome. Prominent fractures also surround the dome and run through smaller, bright regions found within the crater.

MNore: http://www.jpl.nasa.gov/news/news.php?feature=6168
Title: Occator Crater and Ceres' Brightest Spots
Post by: Rick on Apr 02, 2016, 08:24:47
Occator Crater and Ceres' Brightest Spots

One year after taking up its new residence in the solar system, Dawn is continuing to witness extraordinary sights on dwarf planet Ceres. The indefatigable explorer is carrying out its intensive campaign of exploration from a tight orbit, circling its gravitational master at an altitude of only 240 miles (385 kilometers).

Even as we marvel at intriguing pictures and other discoveries, scientists are still in the early stages of putting together the pieces of the big puzzle of how (and where) Ceres formed, what its subsequent history has been, what geological processes are still occurring on this alien world and what all that reveals about the solar system.

More: http://dawnblog.jpl.nasa.gov/2016/03/31/dawn-journal-march-31-3/
Title: Dawn Journal - July 27, 2016
Post by: Rick on Aug 22, 2016, 09:51:43
Dawn Journal - July 27, 2016

Humankind dispatched Dawn on an extraordinary extraterrestrial expedition in 2007. It visited Mars briefly in 2009 and spent 14 months orbiting protoplanet Vesta in 2011-2012, revealing fascinating details of that uncharted, alien world. After traveling for another two and a half years through the interplanetary void, the spacecraft arrived at Ceres in March 2015. It has now conducted an outstandingly successful exploration of the only dwarf planet in the inner solar system. Dawn greatly surpassed its objectives at both Vesta and Ceres, accomplishing well more than was envisioned when NASA decided to undertake this ambitious mission. Having realized its raison d'être, the official end of Dawn's prime mission was  June 30.

More: http://dawn.jpl.nasa.gov/mission/journal_07_27_16.html
Title: What's Inside Ceres? New Findings from Gravity Data
Post by: Rick on Aug 22, 2016, 09:53:05
What's Inside Ceres? New Findings from Gravity Data

In the tens of thousands of photos returned by NASA's Dawn spacecraft, the interior of Ceres isn't visible. But scientists have powerful data to study Ceres' inner structure: Dawn's own motion.

Since gravity dominates Dawn's orbit at Ceres, scientists can measure variations in Ceres' gravity by tracking subtle changes in the motion of the spacecraft. Using data from Dawn, scientists have mapped the variations in Ceres' gravity for the first time in a new study in the journal Nature, which provides clues to the dwarf planet's internal structure.

"The new data suggest that Ceres has a weak interior, and that water and other light materials partially separated from rock during a heating phase early in its history," said Ryan Park, the study's lead author and the supervisor of the solar system dynamics group at NASA's Jet Propulsion Laboratory, Pasadena, California.

More: http://www.jpl.nasa.gov/news/news.php?feature=6583
Title: New Ceres Views as Dawn Moves Higher
Post by: Rick on Nov 21, 2016, 09:13:28
New Ceres Views as Dawn Moves Higher

The brightest area on Ceres stands out amid shadowy, cratered terrain in a dramatic new view from NASA's Dawn spacecraft, taken as it looked off to the side of the dwarf planet.

Occator Crater, with its central bright region and secondary, less-reflective areas, appears quite prominent near the limb, or edge, of Ceres. At 57 miles (92 kilometers) wide and 2.5 miles (4 kilometers) deep, Occator displays evidence of recent geologic activity. The latest research suggests that the bright material in this crater is comprised of salts left behind after a briny liquid emerged from below, froze and then sublimated, meaning it turned from ice into vapor.

Take a look: http://www.jpl.nasa.gov/news/news.php?feature=6678
Title: Re: NASA's Dawn mission to the asteroids
Post by: doug on Nov 21, 2016, 09:31:34
     An incredible image .... pity they can`t land there and get some samples.....
Title: Where is the Ice on Ceres?
Post by: Rick on Dec 20, 2016, 08:45:34
Where is the Ice on Ceres?

At first glance, Ceres, the largest body in the main asteroid belt, may not look icy. Images from NASA's Dawn spacecraft have revealed a dark, heavily cratered world whose brightest area is made of highly reflective salts -- not ice. But newly published studies from Dawn scientists show two distinct lines of evidence for ice at or near the surface of the dwarf planet. Researchers are presenting these findings at the 2016 American Geophysical Union meeting in San Francisco.

"These studies support the idea that ice separated from rock early in Ceres' history, forming an ice-rich crustal layer, and that ice has remained near the surface over the history of the solar system," said Carol Raymond, deputy principal investigator of the Dawn mission, based at NASA's Jet Propulsion Laboratory, Pasadena, California.

Water ice on other planetary bodies is important because it is an essential ingredient for life as we know it. "By finding bodies that were water-rich in the distant past, we can discover clues as to where life may have existed in the early solar system," Raymond said.

Ice is everywhere on Ceres

More: http://www.jpl.nasa.gov/news/news.php?feature=6703
Title: Re: NASA's Dawn mission to the asteroids
Post by: Rick on Feb 19, 2017, 22:06:27
A deep-space robotic emissary from Earth is continuing to carry out its extraordinary mission at a distant dwarf planet. Orbiting high above Ceres, the sophisticated Dawn spacecraft is hard at work unveiling the secrets of the exotic alien world that has been its home for almost two years.

Dawn’s primary objective in this sixth orbital phase at Ceres (known as extended mission orbit 3, XMO3 or "this sixth orbital phase at Ceres") is to record cosmic rays. Doing so will allow scientists to remove that "noise" from the nuclear radiation measurements performed during the eight months Dawn operated in a low, tight orbit around Ceres. The result will be a cleaner signal, revealing even more about the atomic constituents down to about a yard (meter) underground. As we will see below, in addition to this ongoing investigation, soon the adventurer will begin pursuing a new objective in its exploration of Ceres.

More: http://dawn.jpl.nasa.gov/mission/journal_01_31_17.html
Title: Dawn Discovers Evidence for Organic Material on Ceres
Post by: Rick on Feb 19, 2017, 22:17:57
Dawn Discovers Evidence for Organic Material on Ceres

NASA's Dawn mission has found evidence for organic material on Ceres, a dwarf planet and the largest body in the main asteroid belt between Mars and Jupiter. Scientists using the spacecraft's visible and infrared mapping spectrometer (VIR) detected the material in and around a northern-hemisphere crater called Ernutet. Organic molecules are interesting to scientists because they are necessary, though not sufficient, components of life on Earth.

More: http://www.jpl.nasa.gov/news/news.php?feature=6751
Title: Dawn Identifies Age of Ceres' Brightest Area
Post by: Rick on Mar 24, 2017, 09:21:47
Dawn Identifies Age of Ceres' Brightest Area

The bright central area of Ceres' Occator Crater, known as Cerealia Facula, is approximately 30 million years younger than the crater in which it lies, according to a new study in the Astronomical Journal. Scientists used data from NASA's Dawn spacecraft to analyze Occator's central dome in detail, concluding that this intriguing bright feature on the dwarf planet is only about 4 million years old -- quite recent in terms of geological history.

Researchers led by Andreas Nathues at the Max Planck Institute for Solar System Research (MPS) in Gottingen, Germany, analyzed data from two instruments on board NASA's Dawn spacecraft: the framing camera, and the visible and infrared mapping spectrometer.

The new study supports earlier interpretations from the Dawn team that this reflective material -- comprising the brightest area on all of Ceres -- is made of carbonate salts, although it did not confirm a particular type of carbonate previously identified. The secondary, smaller bright areas of Occator, called Vinalia Faculae, are comprised of a mixture of carbonates and dark material, the study authors wrote.

More: https://www.jpl.nasa.gov/news/news.php?feature=6766
Title: Ice in Ceres' Shadowed Craters Linked to Tilt History
Post by: Rick on Mar 24, 2017, 09:23:39
Ice in Ceres' Shadowed Craters Linked to Tilt History

Dwarf planet Ceres may be hundreds of millions of miles from Jupiter, and even farther from Saturn, but the tremendous influence of gravity from these gas giants has an appreciable effect on Ceres' orientation. In a new study, researchers from NASA's Dawn mission calculate that the axial tilt of Ceres -- the angle at which it spins as it journeys around the sun -- varies widely over the course of about 24,500 years. Astronomers consider this to be a surprisingly short period of time for such dramatic deviations.

Changes in axial tilt, or "obliquity," over the history of Ceres are related to the larger question of where frozen water can be found on Ceres' surface, scientists report in the journal Geophysical Research Letters. Given conditions on Ceres, ice would only be able to survive at extremely cold temperatures -- for example, in areas that never see the sun.

More: https://www.jpl.nasa.gov/news/news.php?feature=6787
Title: Ceres' Temporary Atmosphere Linked to Solar Activity
Post by: Rick on Apr 07, 2017, 09:48:29
Ceres' Temporary Atmosphere Linked to Solar Activity

Ceres is the largest object in the asteroid belt that lies between Mars and Jupiter. When energetic particles from the sun hit exposed ice and ice near the surface of the dwarf planet, it transfers energy to the water molecules as they collide. This frees the water molecules from the ground, allowing them to escape and create a tenuous atmosphere that may last for a week or so.

"Our results also have implications for other airless, water-rich bodies of the solar system, including the polar regions of the moon and some asteroids," said Chris Russell, principal investigator of the Dawn mission, also at UCLA. "Atmospheric releases might be expected from their surfaces, too, when solar activity erupts."

More: https://www.jpl.nasa.gov/news/news.php?feature=6802
Title: Dwarf planet Ceres is an 'ocean world' with sea water beneath surface
Post by: Rick on Aug 11, 2020, 11:55:30
Dwarf planet Ceres is an 'ocean world' with sea water beneath surface, mission finds

The dwarf planet Ceres – long believed to be a barren space rock – is an ocean world with reservoirs of sea water beneath its surface, the results of a major exploration mission showed on Monday.

More: https://www.theguardian.com/science/2020/aug/10/planet-ceres-ocean-world-sea-water-beneath-surface
Title: Why so salty, Ceres? Is it on account of your ...
Post by: Rick on Aug 11, 2020, 11:56:46
Why so salty, Ceres? Is it on account of your underground oceans and cryovolcanism?

Data from NASA's now-defunct Dawn spacecraft orbiting Ceres has shown that the largest object in the Solar System's asteroid belt has sub-surface oceans and recent volcanic activity, according to a group of papers published in Nature journals.

In the first study led by NASA JPL's Carol Raymond, the geological scientists based their findings on data collected by the Dawn space probe, which orbited Ceres from 2015 to 2018 before it ran out of fuel.

More: https://www.theregister.com/2020/08/11/ceres_underground_oceans_volcanism/