NASA’s re-purposed STARDUST- NeXT spacecraft is set to flyby Comet Tempel 1 at a distance of just 200 km on Valentine’s Day – February 14, 2011 at about 8:36 p.m. PST. The encounter marks the first time that a comet has been visited twice by probes from Earth. The revisit also provides the first opportunity for up-close observations of a comet both before and after a single orbital pass around the sun.
Comet Tempel 1 was first visited by NASA’s Deep Impact comet smashing mission in July 2005. Deep Impact delivered a 375 kg projectile into the path of Temple 1 that resulted in a high speed impact directly into the comet nucleus.
The cosmic collision of about 10.2 km/sec (22,800 miles/hour) ejected a cloud of debris that was studied by the Deep Impact spacecraft as well as an armada of orbiting and ground based telescopes. The impact crater itself was obscured by the debris cloud. The spacecraft did find the first evidence of surface ice on a comet instead of just inside a comet. Stardust NExT will take images and spectra of Tempel 1 and hunt for the impact crater.
According to the latest update posted at the STARDUST- NeXT mission website on Jan 6; “The spacecraft is healthy and began the New Year with a cold boot to clear a memory address latch-up that had occurred late in 2010. This cold boot clears the latched line and resets the memory to its factory settings.”
The reboot was completely successful and sets the probe up to accomplish the missions science objectives. On board optical navigation cameras were scheduled to take a new set of images on Jan. 6.
The update further states that the mission plan has now changed substantially to accommodate two new challenges. First the estimated fuel remaining on board is lower than expected. Second, the optical navigation cameras failed to detect the comet in the prior set of images in December.
The optical cameras provide the key information to precisely navigate the probe to the comet. “Current estimates show that the comet may not be bright enough to detect with the Navcam until the latter half of January,” states the update.
As a result of the lower fuel estimate the remaining trajectory maneuvers (TCM’s) have been adjusted to January 31, February 7, and February 12. No science images will be taken until the last 7 days prior to the Feb 14 encounter.
Caption: Video of Comet Tempel 1 as NASA’s Deep Impact comet spacecraft delivers a projectile which smashed into the comet in July 2005. NASA’s STARDUST- NeXT probe is set to flyby Comet Tempel 1 on February, 14, 2011. The probe will collect numerous high resolution images of the coma and nucleus and hunt for the elusive 2005 impact crater.
The team states that these changes will provide “positive fuel margin through encounter …. and places the TCMs at times best able to accommodate late detection of the comet”.
The engineering team is building new approach sequences to accommodate these significant changes to the approach and Comet Tempel 1 encounter on Feb 14.
A briefing by the science team will be carried live on NASA TV on Jan. 19 at 2 PM EST
The Stardust spacecraft accomplished its original goal of flying through a dust cloud surrounding the nucleus of comet Wild 2 in Jan. 2004. The probe successfully gathered particles of cometary material during the flyby, The comet particles were returned to Earth aboard a sample return capsule which landed in the Utah desert in January 2006.
No one is giving up hope for Spirit. Not Yet. And neither should you.
It’s too soon to turn out the lights. Indeed NASA is stepping up operational efforts to contact the plucky rover – More communications commands; more listening time; more frequencies. Spirit last communicated with mission controllers back on Earth on March 22, 2010. The rover entered hibernation mode – some nine months ago – as the available sunlight to power the life giving solar panels was diminishing. NASA hopes to reawaken Spirit from a long slumber and reignite her breakthrough campaign of exploration and discovery from a scientific goldmine on the surface of the red planet.
“The sun is still rising on Mars,” says Ray Arvidson in an interview from Washington University in St. Louis. Arvidson is the deputy principal investigator for the Spirit and Opportunity rovers.
“We will keep listening for many months if necessary,” Steve Squyres informed me. Squyres is the Principal Scientific Investigator for the Mars Exploration Rover mission.
By the time of the last dispatch from Mars, Spirit had lasted for nearly six years of bonus mission time – during the extended mission phase – light years beyond the 3 month “warranty” proclaimed by NASA as the mission began back in January 2004.
At Spirit’s location in the southern hemisphere of Mars, Southern Summer has not yet arrived. Right now it’s mid Southern Spring and daylight hours are increasing. And Summer doesn’t even start until mid-March 2011. The question is whether Spirit’s unheated electronics components have endured the extremely harsh and frigidly cold conditions of her 4th winter on Mars – her coldest ever. At about -100 C … Imagine Antarctica !
“The amount of solar energy available for Spirit is still increasing every day for the next few months,” said Mars Exploration Rover Project Manager John Callas of NASA’s Jet Propulsion Laboratory (JPL) , Pasadena, Calif. “As long as that’s the case, we will do all we can to increase the chances of hearing from the rover again.”
“We’re stepping up our efforts to contact Spirit — doubling down on her, as it were,” tweeted JPL mars rover driver Scott Maxwell.
And all those negative stories you may have read about Spirit being “Still Stuck” … well they totally missed the point.
In the final Sols, or Martian days, before falling silent in March 2010, there was dramatic movement by Spirit. “During the last 9 drives, Spirit actually moved 34 cm. That’s pretty good for a stationary rover,” Arvidson said.
This movement came despite the loss of two of the rover’s six wheels and after many months of methodical testing in the “Mars sand box”. Engineers at JPL devised and tested numerous strategies in attempting to extricate Spirit from the sand trap of soft soil in which she became mired.
Because of the declining sun and available power, Spirit basically just ran out of time to try and completely escape from the sand trap. This left it unable to obtain a favorable tilt for solar energy during the rover’s fourth Martian winter, which began last May.
Many members of the rover team are hopeful that they can indeed “Free Spirit” if she awakens from her current hibernation mode.
“I have no idea whether we’ll hear from Spirit again or not… there’s simply no way to predict it,” Squyres told me. “We will keep listening for many months. All we can do is listen”
Even if we never hear from Spirit again, she has accomplished a remarkable series of scientific breakthroughs, far beyond the wildest dreams of the science and engineering teams that built and operate the twins.
Spirit discovered a rock that contained high levels of carbonates, minerals that form in neutral watery conditions that are far more conducive to the formation of life than the acidic watery conditions reported earlier in the mission.
Although Spirit has been stalled at a place called ‘Troy’ since April 2009. she made a significant science discovery at that exact spot. Spirit examined the soil in great detail and found key evidence that water, perhaps as snow melt, trickled into the subsurface fairly recently and on a continuing basis.
While driving on the western edge of an eroded over volcanic feature named ‘Home Plate’, she unknowingly broke through a hard surface crust (perhaps 1 cm thick) and sank into hidden soft sand beneath. At ‘Troy’, Spirit discovered that the crust was comprised of water related sulfate materials and therefore found evidence for the past flow of liquid water on the surface of Mars – a great science discovery!
After mid-March, prospects for reviving Spirit would begin to drop, say NASA officials. Communication strategies would change based on reasoning that Spirit’s silence is due to factors beyond just a low-power condition. Mission-ending damage from the cold experienced by Spirit in the past Martian winter is a real possibility.
Spirit's panoramic camera (Pancam) took the component images during the period from the 2,163rd to 2,177th Martian days, or sols, of Spirit's mission on Mars (Feb. 2 to Feb. 16, 2010). The turret at the end of the rover's arm appears in two places because of movement during that period. Insets in the upper left and lower right corners of the frame show magnified views of the nearby inscribed rectangles within the mosaic. The patch of ground within each rectangle is about 25 centimeters (10 inches) across. The top inset and upper portion of the mosaic include targets within soil layers exposed by the action of Spirit's wheels in April 2009 and examined in detail with instruments on Spirit's arm during the five subsequent months.
Olive pit and Olive leaf are two of the analyzed targets. The investigations determined that, under a thin covering of windblown sand and dust, relatively insoluble minerals are concentrated near the surface and more-soluble ferric sulfates have higher concentrations below that layer. This pattern suggests water has moved downward through the soil, dissolving and carrying the ferric sulfates. The brightness and color of the freshly disturbed soil seen in the center area of the mosaic indicates the this formerly hidden material is sulfate-rich. Before Spirit drove into this patch, the surface looked like the undisturbed ground highlighted in the lower-right inset. Flecks of red material in the surface layer resemble the appearance of the surface layer at other locations where Spirit's wheels have exposed high-sulfate, bright soils. Image Credit: NASA/JPL-Caltech/Cornell University
Spirit entered a low-power fault mode in March 2010 with minimal activity except charging and heating the batteries and keeping its clock running. With most heaters shut off, Spirit’s internal temperatures dipped lower than ever before on Mars. That stress could have caused damage, such as impaired electrical connections, that would prevent reawakening or, even if Spirit returns to operation, would reduce its capabilities.
“Components within the rover electronic module (REM) inside the rover’s warm electronic box (WEB) are experiencing record low temperatures,” said Doug McCuistion, the director of Mars Exploration at NASA Headquarters in Washington, DC, in an interview about Spirit’s predicament. “The expectation is for the REM hardware to reach -55C at the coldest part of the winter. We have tested the REM down to -55C”.
NASA’s Deep Space Network of antennas in California, Spain and Australia has been listening for Spirit daily in coordination with the spacecraft orbiting Mars; Mars Odyssey and Mars Reconnaissance Orbiter. In X-band, the DSN listens for Spirit during one pass each day. The rover team has also been sending commands to elicit a response from the rover even if the rover has lost track of time.
Now, the monitoring is being increased. Additional listening periods include times when Spirit might mistake a signal from NASA’s Mars Reconnaissance Orbiter as a signal from Earth and respond to such a signal. Commands for a beep from Spirit will be sent at additional times to cover a wider range of times-of-day on Mars when Spirit might awaken.
“DSN does an average of 4 “sweep & beep” commands in each day’s pass,” according to JPL spokesman Guy Webster. Also, NASA is listening on a wider range of frequencies to cover more possibilities of temperature effects on Spirit’s radio systems
Millions across Earth enjoyed one of nature’s most awesomely spectacular events during today’s (Jan. 4) partial solar eclipse – the first of four set to occur in 2011. And there was nothing partial about it, for those lucky eyewitnesses where it was visible in parts of Europe, Africa and Central Asia. The eclipse reached its maximum, about 85%, in Sweden. See the maximum stunner above – taken despite pessimistic weather forecasts -by Peter Rosen in Stockholm, Sweden, with more photos from the sequence here at spaceweather.com
Probably the most technically amazing feat is the double solar eclipse captured in one image by renowned astrophotographer Theirry Legault – see below – boasting both the ISS and the Moon on the eclipsed sun’s face. Legault had traveled to the deserts of the Sultanate of Oman, near to the capital of Muscat, for this rare spectacle of nature. The ISS was calculated to be visible in a thin strip barely 11 kilometers wide, according to Astronomie Info news. The ISS transit lasted just about 1 second, speeding by at 28,000 km/sec.
See a global compilation of gorgeous eclipse photos here and comment or send us more. Update 1/6/11: this is a work in progress so please check back again.
New readers photos and eyewitness accounts added below today; as received
Click to enlarge all photos
First up: Double Solar Eclipse by renowned astrophotographer Theirry Legault in Oman
Check out this exciting gallery of images contributed by eclipse watchers from multiple locations around the world, on Flickr
Here is a collection of images and an eyewitness report sent to me by Marco Di Lorenzo, in Pescara, Italy
Marco writes; Pescara is located at 42.467°N and 14.225°E, about in the center of Italy on the Adriatic sea. I chose my location at the new pedestrian bridge because it is a modern structure which offers a nice foreground and also an open, elevated viewpoint. I used a couple of cameras plus a digital video camera. All the cameras were mounted on a tripod.
The weather was cold and the situation didn’t improve in the mid morning. Illumination was comparable to a slightly foggy day. The frigid temperature didn’t encourage people to go out and check. However some people did venture out. Someone asked me some info on eclipses and how to take pictures of it – very hard indeed, especially if you use a cellular phone !
Urijian Poernick sent these photos and description:
“Colorful Solar Eclipse” at Halley Astronomical Observatory, Heesch, The Netherlands
The weather forecast predicted overcast skies with only a few small bright intervals in all parts of The Netherlands. Nevertheless, dozens of members of Halley Astronomical Society and visitors, including many children, challenged the cold winter weather and came together on the flat roof of Halley Astronomical Observatory in The Netherlands.
After sunrise at 7:44 UT (8:44 local time) they all looked at a narrow opening in the cloud deck near the eastern horizon. At 8:00 UT the sun showed itself: first we saw the left horn of the eclipse and a few moments later the right one.
Due to the clouds and veils it was a very colorful eclipse, with all tints of red and yellow. After twenty minutes the sun and the moon disappeared behind the overcast skies again and they didn’t come back before the end of the eclipse (9:39 UT).
During this short period everyone could watch the eclipse through the telescope and we were all enthusiastic. It was a beautiful spectacle! www.sterrenwachthalley.nl
Gianluca Masi is the National Coordinator of Astronomers Without Borders in Italy and captured this pair of photos from partially overcast Rome, Italy. The clouds contributed to make for a delightfully smoky eclipsed sun
Edwin van Schijndel sent me this report from the Netherlands:
I made some pictures in the southwest of the Netherlands. The weather conditions were not so good in the early morning, most places were covered by clouds so we decided to move about 70 miles to the southwest from our hometown. Finally we stopped not far from the city of Bergen op Zoom and were able to see sunrise while most of the sun was covered. It was splendid!
Unfortunately there came more clouds so the rising sun disappeared and we drove 20 miles to the north just before Rotterdam and the sky was more clear at this place. Again we took some pictures but the maximum covering of the sun had been a few minutes before. After all this wasn’t really a pity, we were very lucky to have seen the rising of the sun and be able to make some nice pictures of the partial eclipse. Many people in the Netherlands saw less or even nothing.
Send us or comment more solar eclipse photos to post here. ken : [kremerken at yahoo.com]
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More Readers Photos and Eyewitness Accounts. Beautiful, Thanks ! ken
Story and Photos sent me by Stefano De Rosa. Turin, Italy
Early in the morning, I moved to a site close to Turin (Italy) where the forecast was not so bad as in my city to try to observe and photograph the partial solar eclipse. Unfortunately, when I arrived it was cloudy and foggy and so decided to go back home. Technical details: Canon Eos 1000d, F/22; 150-500mm lens @ 500mm; ISO. 1/1600 sec
Suddenly, as I was sadly driving on the motorway, close to the city of Alessandria, noticed a little break on the clouds from my rearview mirror: I stopped the car and, after a quick set up, managed to capture the crescent Sun!
http://ofpink.wordpress.com Well, I hope you carefully looked back before hitting the brakes ! – ken
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Story and Photos sent me by Roy Keeris, Zeist, The Netherlands
Me and a friend (Casper ter Kuile) wanted to see the eclipse from The Netherlands. If clouds should intervene, we planned to drive a little (max. a couple of hours) to a place with a better chance for a clear sky. During the night we checked weather forecasts and satellite images. We were pretty unsure if we would succeed in seeing the eclipse, because it was pretty cloudy, and especially the low clouds tend to be quite unpredictable. In the end we chose to drive to Middelkerke (near Oostende) in Belgium because of a clear spot approaching from the North Sea.
We arrived at the Belgian coast just in time before sunrise. There we witnessed the eclipse from the top of a dune. About 25 minutes after sunrise the sun appeared from behind the lower clouds, just when the eclipse was at its maximum. It was magical!
First we saw the right ‘horn’ and then the left one appeared. From then on we watched the rest of the eclipse and took many pictures. [no pics from Casper ??]
Later we heard that despite the clouds, many people in The Netherlands were able to see the eclipse. There was a long stretch with a clear zone in the clouds- near the border of Germany.
If they had a clear horizon, people could look underneath the clouds and were just able to see the sunrise. I could even have seen it at home from my apartment on the 13th floor! But the trip was fun. It’s always nice to hunt for the right place to be at these events.
Here are some pictures I took from Middelkerke. They were shot with a Canon 400D in combination with a Meade ETS-70 telescope and a Tamron 20-200mm lens.
Thanks – Yes the hunt is half the fun. ken
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Story and Photos sent me by Igal Pat-El, Director, Givatayim Observatory, Tel Aviv, Israel
We took some images of the Jan. 4 Solar Eclipse from the Givatayim Observatory, just near Tel-Aviv, Israel. We were pleased to have Prof. Jay Passachoff as a guest during the eclipse. We had a live broadcast in plan but we had to cancel it due to heavy rain from the first contact, therefore we closed the dome’s shutter and went to the balcony trying to take some quick photos of the eclipse.
We had the portable PST Coronado CaK telescope with a Ca filter On a Alt-Az mount (we could not do any alignment due to the rain). We took about 5 images against all odds in this very dim filter, using the Orion SS II Planetary imager, all of them through the haze and clouds.
Thanks, Igal. Another good lesson learned. Take a chance. You never know what you’ll get till you try !
I’ve combined Igal’s photos into a collage for an enhanced view. ken
See more photos and a video in comments section below
“I enjoy seeing our rover again,“ says Steve Squyres in an exclusive for Universe Today. Squyres is the top scientist for the Opportunity and Spirit Mars rovers.
NASA’s Opportunity rover was just been photographed from Mars Orbit while perched at the precipice of Santa Maria crater – just meters away from the edge of the Southwest rim. The photo was taken on New Year’s Eve, Dec. 31, 2010 on Sol 2466 of the mission which has lasted nearly 7 years ! Opportunity landed on Mars on Jan. 24, 2004.
“Well, it’s always great to see images like that,” Steve Squyres just informed me after seeing the new photos of Opportunity. Squyres, of Cornell University, is the Principal Scientific Investigator for NASA’s Spirit and Opportunity Mars rovers.
“This one reminds me a lot of the first time we ever saw a rover from orbit, just after Opportunity had arrived at the rim of Victoria crater. It’s a very evocative scene, and it’s hard not to project certain things onto the rover (“valiant”, “lonely”) when you see it. Mostly, though, I just enjoy seeing our rover again.”
“The last time I laid eyes on Opportunity was about seven and a half years ago, and it’s nice getting another glimpse of her,” said Squyres.
Opportunity arrived at the western rim of Santa Maria on Dec. 16 (Sol 2451) after a long and arduous trek of some 19 km since departing from Victoria Crater over 2 years ago in September 2008.
The rover has been exploring around the western portion of Santa Maria crater since arriving and is now heading to the southeast rim which possesses deposits of hydrated minerals.
Opportunity drove some 40 meters south along the steep rim from the initial location at “Palos” Promontory and then bumped incrementally further up to the edge on Sol 2464 at a place dubbed “Wanahani”.
The rover was photographed from Mars orbit while perched at “Wanahani” on New Years Eve, Dec 31, 2010 on Sol 2466.
“We are driving the vehicle in a counterclockwise direction around Santa Maria to reach the very interesting hydrated sulfates on the other side,” according to Ray Arvidson, the deputy principal investigator for the rovers, in an interview from Washington University in St. Louis. “We’ll make 3 stops or more depending on what we see”
Simultaneously to being photographed from orbit, the rover itself was of course merrily snapping a ground level view of Santa Maria. To experience the surface eye view from Opportunity, see our photo mosaic – stitched from the raw images – to display the rovers panoramic perspective whilst gazing outwards from “Wanahani” to the cliffs of Santa Maria on Sols 2464 and 2466.
“Opportunity is imaging the crater interior to better understand the geometry of rock layers as a means of defining the stratigraphy and the impact process, says Matt Golembek, Mars Exploration Program Landing Site Scientist at the Jet Propulsion Laboratory (JPL), Pasadena, Calif.
Santa Maria is a relatively young, 90 meter-diameter impact crater (note blocks of ejecta around the crater), but old enough to collect sand dunes in its interior.
Santa Maria Crater, located in Meridiani Planum, is about 6 kilometers from the rim of Endeavour Crater, which contains spectral indications of phyllosilicates, or clay bearing minerals that are believed to have formed in wet conditions that could have been more habitable than the later acidic conditions in which the sulfates Opportunity has been exploring formed.
Data from the CRISM mineral mapper aboard MRO data show indications of hydrated sulfates on the Southeast edge of the Santa Maria Crater at which Opportunity is planning on spending the upcoming solar conjunction. After that, Opportunity will traverse to the Northwest rim of Endeavour Crater, aided tremendously by HiRISE images like the one here for navigation and targeting interesting smaller craters along the way.
A robot from Earth is celebrating New Years on Mars by snapping another amazing set of “Postcards from the Edge” while perched near the sharp edge of a crater cliff on the red planet. NASA’s Opportunity rover is now stationed just meters away from a new precipice at the stunningly beautiful crater named Santa Maria. The twin rovers mark their 7th anniversary on Mars this week. See martian postcard mosaics above and below.
Craters expose the hidden history of Mars and permit scientists a path to explore the past geologic epochs which otherwise would remain buried and inaccessible.
Santa Maria is an exciting find because it appears to be relatively new and unweathered – on the order of possibly just a few million years old. Researchers are eager to drive around the rim in order to explore deposits of water bearing minerals that contain valuable clues to the flow of liquid water on ancient Mars.
The golf cart sized rover arrived this week (Dec. 29) at an outlook nicknamed “Wanahani” near the southern edge of Santa Maria. Opportunity arrived at the western rim of Santa Maria on Dec. 16. Just before Christmas, she drove about 20 meters south along the steep rim from the initial location at Palos Promontory and then bumped incrementally further up to the edge (Sol 2464) .
But there is no time to party and relax. The rover will soon resume driving to the next location – nicknamed “Yuma”. It will continue farther around the football field sized crater – measuring some 90 meters (295 ft) in diameter – to reach the exposures of sulfated hydrates located at the southeast portion of the crater near “Yuma”.
Opportunity must be in position at an important science target before mid January and the onset of solar conjunction and a temporary communications black out with Earth. The rover will remain stationary during conjunction.
At Wanahani, Opportunity is now hurriedly toiling away over the New Year’s period to collect a pair of long baseline, high resolution stereo image mosaics using it’s panoramic, multispectral imaging camera. See our initial Wanahani mosaics assembled here from the navigation camera images just received on Earth (Sol 2464).
The team is using all 13 filters on the filter wheels of the panoramic camera, according to Ray Arvidson, the deputy principal investigator for the rovers, in an interview from Washington University in St. Louis. Over the course of several days, the left and right “eyes” of the panoramic camera will gather data at various wavelengths to maximize the collection of spectral information about the hydrated minerals located in the craters interior.
Data downlink is limited by the available amount of flash memory aboard Opportunity and is the Achilles heel of rover operations. Virtually all the pictures and science is streaming back to Earth via NASA’s long lived Mars Odyssey orbiter. The team is working to get all the acquired science data offloaded as swiftly as possible,
Arvidson said that the team hopes that the meteor impact that excavated the crater also blasted some of these scientifically fascinating rocks free to spots which are more easily accessible – just outside the rim for close up analysis. Additional imaging and spectral data is also being collected from Mars orbit this new year’s weekend in hopes of quickly directing the rover to the best locations for science in the limited time available.
Opportunity will study the relatively fresh and uneroded ejecta rocks using all the instruments located at the end of the robotic arm. One target will be selected for a longer duration study during the period of solar conjunction, said Arvidson.
The rover team is naming places visited around the crater rim after islands visited by Columbus during his voyages of expedition and discovery to the New World starting in 1492. The Santa Maria was the largest of the three ships used during his first voyage.
Opportunity will resume her long term trek to Endeavour crater after the end of solar conjunction in mid February. The western rim of Endeavour is about 6 km distant. Endeavour is a very compelling science target because it shows significant signatures for clay minerals which formed in the presence of neutral bodies of liquid water on Mars, billions of years ago.
Spirit and Opportunity celebrate 7 Years on Mars this month since the dynamic duo landed in January 2004. Look for my story soon.
Spectacular new images of a gorgeous gaping hole on Mars are streaming back to Earth from NASA’s Opportunity Mars Rover. So let’s take a 3 D stroll placing all of us at Santa Maria Crater – “On Mars”. Via the photo mosaics above and below, we will circle in three dimensions about the stunningly beautiful Santa Maria Crater. At the southeast portion of the rim, the crater also possesses a scientific goldmine of hydrated mineral deposits. These minerals are indicative of the past flow of liquid water on Mars, an essential requirement for the formation of life.
Opportunity made landfall at the western edge of Santa Maria on Dec. 15 (Sol 2450) after a long and arduous journey of some 19 km since departing from Victoria Crater over 2 years ago in September 2008. She crawled closer to the rim the next day on Dec. 16 (Sol 2451) unveiling a magnificent vista of jumbled ejecta rocks, steep sloped cliffs and undulating sand dunes across the crater floor.
“Santa Maria is a relatively fresh impact crater. It’s geologically very young, hardly eroded at all, and hard to date quantitatively. On the order of 10 million years old or less,” said Ray Arvidson in an interview from Washington University in St. Louis. Arvidson is the deputy principal investigator for the Spirit and Opportunity rovers.
“Santa Maria is the freshest big guy that Opportunity has seen and has a raised rim,” Arvidson told me. “It is much younger than Endurance Crater which Opportunity visited a few months after landing on Mars way back in 2004 and is roughly the same diameter.” See the entire Opportunity traverse map below.
“The crater is young enough that the interesting hydrate outcrops may not be coated with the nanophase iron oxide dust. There is virtually no erosion. We can see the ejecta rays and blocks,“ said Arvidson.
While sitting just five meters from the rim on Dec. 16, Opportunity imaged the football field sized crater – some 90 m wide – with both its left and right eye navigation cameras. A mosaic of these images was stitched together by NASA to create a stunning 360 degree stereo panoramic vista. The images are snapped from the same height seen by an adult to give the perspective that a human eye would see when standing “On Mars”.
The crater is the centerpiece of the stereo image above, which shows the crater’s sharp rim and rocks ejected from the impact that had excavated the crater. You will need to whip out your red-cyan stereo glasses to experience the full three-dimensional effect of the scene. Be sure to wear the red lens on the left, and try not to fall off the cliff.
Click here for the entire 360-degree high resolution stereo view – its 10 MB in all. South is at the center. North is at both ends. The view is presented as a cylindrical-perspective projection. The wheel tracks left behind in the Martian dirt – as the rover approached the crater – are seen at the far right and are also highlighted in our 2 D mosaic below.
Off in the distance, several portions of the rim of Endeavour Crater are visible as bumps on the horizon. Endeavour is the ultimate target of Opportunity’s long term trek across the Martian dunes at the Meridiani Planum region and is some 22 kilometers in diameter.
“Endeavour shows significant signatures of phylloslicates, or clay minerals, and water bearing sulfate minerals which formed in the presence of liquid water,” Arvidson explained. “The phyllosilicates formed at the crater rim about 3.8 to 4.2 Billion years ago and predate the sedimentary rocks which are younger than 3.8 billion years.”
Pictured below is a collection of stereo photo mosaics for a North to South up close tour around the rim of Santa Maria. Several of the images were created by members of unmannedspaceflight.com.
“Opportunity will drive in a counterclockwise direction around Santa Maria to reach the very interesting hydrated sulfates on the other side. We’ll make 3 stops or more depending on what we see”
“On Dec. 19 (Sol 2454) we bumped the vehicle even closer to the rim from the initial approach point, to a promontory we’ve nicknamed ‘Palos’, stated Arvidson. “Opportunity was a mere 2.5 meters from the edge. At ‘Palos’, the rover collected the first set of long baseline, high resolution stereo images for creating a 3 D digital elevation map.”
“The coves at Santa Maria will be named after the islands which Columbus visited, using the native American language. All the rocks and boulders strewn about will be named after the sailors on the voyage with Columbus,” explained Arvidson.
“This past weekend we drove about 20 meters southeast towards the second location named ‘Wanahani’. On Tuesday of this week (Dec. 28) we bumped to the edge. The plan is to photograph the ejecta rocks and collect the next set of long baseline, high resolution stereo images.”
The third stop – which must be reached before Solar Conjunction in mid January 2011- will take Opportunity to the science hot spot detected by the powerful CRISM mineral mapping spectrometer circling above Mars aboard NASA’s Mars Reconnaissance Orbiter (MRO).
“With CRISM we are trying to cover all the rim segments to better understand the nature and geologic setting of the iron and magnesium smectite clay mineral exposures. The southeast portion of Santa Maria is generally the location of the CRISM spectra that show hydrated sulfates. Opportunity will go to the southeast rim and try and find a nice outcrop on the rim side to do measurements to field verify the expected mineralogy,” explained Arvidson.
“We might do a toe dip with the wheels but there is no plan to go inside.”
“We will use the Rock Abrasion Tool (RAT) to drill into a selected target. That spot will be named after ‘Columbus’.
The exposures of hydrated sulfates have a bright toned appearence in the images.
“With the sun over the camera’s shoulder there is a phenomenon called opposition effect in which rocks and soils become particularly bright when the sun-camera-surface line up, Arvidson told me. “But, it also may be that the bright looking rocks are intrinsically bright and not coated with the nanophase iron oxide coatings we have seen on previous outcrops. All in the realm of testable working hypotheses.”
“On Dec. 30 we are planning another CRISM spectral mapping campaign with MRO over Santa Maria,” said Arvidson. “Using a new technique which gimbals, or swivels, the CRISM optics we hope to use a pixel overlap technique to improve the ground resolution from 18 meters across to 6 meters across. This data will be used in tactical decisions about where to drive on Mars.”
Read more of my interview with Ray Arvidson in the next feature story describing the exciting plan for science exploration at Santa Maria and Endeavour, the outlook for Spirit and more – along with new mosaics from “Wanahani”.
NASA is using its powerful science surveyor orbiting more than 241 kilometers above Mars to target the surface explorations of the long lived Opportunity rover to compelling science targets on the ground. Opportunity is currently on a long term trek to the giant crater named Endeavour, some 22 kilometers in diameter, which shows significant signatures of clays and water bearing sulfate minerals which formed in the presence of flowing liquid water billions of years ago.
An armada of orbiters and rovers from Earth are carrying out a coordinated attack plan to unlock the mysteries of the red planet, foremost being to determine whether life ever arose on Mars.
On Dec. 15 (Sol 2450), Opportunity arrived at Santa Maria crater which is just 6 km distant from the western rim of Endeavour. Over the past 2 years, the rover has traversed more than two thirds of the 19 km distance from Victoria crater -her last big target – to Endeavour.
High resolution spectral and imaging mappers aboard NASA’s Mars Reconnaissance Orbiter (MRO) are enabling researchers on the rover team to prioritize targets and strategically guide Opportunity to the most fruitful locations for scientific investigations.
The on board CRISM mapping spectrometer has detected clay minerals, or phyllosilicates, at multiple locations around Endeavour crater including the western rim closest to Opportunity. CRISM is the acronym for Compact Reconnaissance Imaging Spectrometer for Mars. Images from MRO’s HiRISE camera are utilized to scout out the safest and most efficient route. See maps above and below.
“This is the first time mineral detections from orbit are being used in tactical decisions about where to drive on Mars,” said Ray Arvidson of Washington University in St. Louis. Arvidson is the deputy principal investigator for the Spirit and Opportunity rovers and a co-investigator for CRISM.
Clay minerals are a very exciting scientific find because they can form in more neutral and much less acidic aqueous environments which are more conducive to the possibility for the formation of life. They have never before been studied up close by science instruments on a landed mission.
Opportunity may soon get a quick taste of water bearing sulfate minerals at Santa Maria because spectral data from CRISM suggest the presence of sulfate deposits at the southeast rim of the crater. Opportunity has previously investigated these sulfate minerals at other locations along her circuitous traverse route – but which she discovered without the help of orbital assets.
“We’ve just pulled up to the rim of Santa Maria, and the workload is very high,” Steve Squyres informed me. Squyres, of Cornell University, is the Principal Scientific Investigator for NASA’s Spirit and Opportunity Mars rovers.
Opportunity drove to within about 5 meters of the crater rim on Dec. 16 (Sol 2451). JPL Mars rover driver Scott Maxwell tweeted this message ; “Today’s NAVCAM mosaic of Santa Maria Crater. Woo-hoo! Glorious and beautiful!” and this twitpic
The rover will conduct an extensive science campaign at Santa Maria by driving to different spots over the next several weeks and gathering data to compare observations on the ground to those from CRISM in orbit.
Santa Maria crater appears to be relatively fresh and steep walled and was likely created by a meteor strike only a few million years ago. Endeavour is an ancient crater with a discontinuous rim that is heavily eroded at many points. By exploring craters, scientists can look back in time and decipher earlier geologic periods in Mars history.
Scientists believe that the clay minerals stem from an earlier time period in Martian history and that the sulfate deposits formed later. Mars has experiences many episodes of wet environments at diverse locations in the past and climate-change cycles persist into the present era.
After the upcoming Solar Conjunction in February 2011, Opportunity will depart eastwards for the last leg of the long march to Endeavour. She heads for a rim fragment dubbed Cape York which spectral data show is surrounded by exposures of water bearing minerals. Cape York is not yet visible in the long distance images because it lies to low. See maps below.
Thereafter, Opportunity alters direction and turns south towards her next goal –
Cape Tribulation – which is even more enticing to researchers because CRISM has detected exposures of the clay minerals formed in the milder environments more favorable to life. Cape Tribulation has been clearly visible in rover images already taken months ago in early 2010.
Opportunity could reach Endeavour sometime in 2011 if she can continue to survive the harsh environment of Mars and drive at her current accelerated pace. Opportunity arrived at Mars in January 2004 for a planned 90 day mission. The rover has far surpassed all expectations and will soon celebrate 7 earth years of continuous operations on the red planet. Virtually all the data from Spirit and Opportunity are relayed back to Earth via NASA’s Mars Odyssey orbiter.
Opportunity used its panoramic camera in a super-resolution technique to record this view of the horizon on Sol 2298 (July 11, 2010) which shows the western rim of Endeavour Crater, including the highest ridge informally named “Cape Tribulation”. CRISM data revealed exposures of clay minerals at Cape Tribulation.
Opportunity’s Path on Mars Through Sol 2436
The red line shows where Opportunity has driven from the place where it landed in January 2004 — inside Eagle Crater, at the upper left end of the track — to where it reached on the 2,436th Martian day, or sol, of its work on Mars (Nov. 30, 2010). The map covers an area about 15 kilometers (9 miles) wide. North is at the top. Subsequent drives brought Opportunity to Santa Maria Crater, which is about 90 meters (295 feet) in diameter. After investigating Santa Maria the rover heads for Endeavour Crater. The western edge of 22-kilometer-wide (14-mile-wide) Endeavour is in the lower right corner of this map. Some sections of the discontinuous raised rim and nearby features are indicated with informal names on the map: rim segments “Cape York” and “Solander Point”; a low area between them called “Botany Bay”; “Antares” crater, which formed on sedimentary rocks where the rim was eroded down; and rim fragment “Cape Tribulation,” where orbital observations have detected clay minerals. The base map is a mosaic of images from the Context Camera on NASA’s Mars Reconnaissance Orbiter.
There’s a new theory for why Saturn’s moon Iapetus looks like a walnut. The moon has a mysterious large ridge that covers more than 75 percent of the moon’s equator. Figuring out the reason for the ridge, say researchers from Washington University in St. Louis, has been a tough nut to crack. But they propose that at one time Iapetus itself had its very own moon, and the orbit of this mini-moon-around-another-moon would have decayed because of tidal interactions with Iapetus, and those forces would have torn the sub-satellite apart, forming a ring of debris around Iapetus that would eventually slam into the moon near its equator.
This is not the nuttiest proposal ever…
The ridge on Iapetus is 100 kilometers (62 miles) wide and at place, 20 kilometers (12 miles) high. (The peak of Mount Everest, by comparison, is 8.8 km (5.5 miles) above sea level.) Iapetus itself is 1,470 km across, and is the 11th largest moon in the Solar System.
Professor William McKinnon and his former doctoral student, Andrew Dombard — now from the University of Illinois Chicago — came up with this idea.
“Imagine all of these particles coming down horizontally across the equatorial surface at about 400 meters per second, the speed of a rifle bullet, one after the other, like frozen baseballs,” said McKinnon. “Particles would impact one by one, over and over again on the equatorial line. At first the debris would have made holes to form a groove that eventually filled up.”
“When you have a debris ring around a body, the collisional interactions steal energy out of the orbit,” Dombard said. “And the lowest energy state that a body can be in is right over the rotational bulge of a planetary body — the equator. That’s why the rings of Jupiter, Saturn, Uranus and Neptune are over the equator.”
“We have a lot of corroborating calculations that demonstrate that this is a plausible idea,” added Dombard, “but we don’t yet have any rigorous simulations to show the process in action. Hopefully, that’s next.”
Other ideas for how the ridge was created are volcanism or mountain-building forces.
“Some people have proposed that the ridge might have been caused by a string of volcanic eruptions, or maybe it’s a set of faults,” said McKinnon. “But to align it all perfectly like that — there is just no similar example in the solar system to point to such a thing.”
Dombard said there are three critical observations that any model for the formation of the ridge has to satisfy: Why the feature is sitting on the equator; why only on the equator, and why only on Iapetus.
Dombard says that Iapetus’s Hill sphere — the zone close to an astronomical body where the body’s gravity dominates satellites — is far bigger than that of any other major satellite in the outer solar system, accounting for why Iapetus is the only body known to have such a ridge.
“Only Iapetus could have had the orbital space for the sub-satellite to then evolve and come down toward its surface and break up and supply the ridge,” he says.
Dombard will make a presentation on the preliminary findings Wed., Dec. 15, 2010, at the fall meeting of the American Geophysical Union in San Francisco. The team also included Andrew F. Cheng of the Johns Hopkins Applied Physics Laboratory, and Jonathan P. Kay, a graduate student at UIC.
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When is an asteroid not an asteroid? When it turns out to be a comet, of course. Has this ever happened before? Why, yes it has. In fact it was just announced December 12, 2010 that the asteroid (596) Scheila has sprouted a tail and coma! This is likely a comet that has been masquerading as an asteroid.
Steve Larson of the Lunar and Planetary Laboratory (LPL), University of Arizona first reported that images of the minor planet (596) Scheila taken on December 11th showed the object to be in outburst, with a comet-like appearance and an increase in brightness from magnitude 14.5 to 13.4. The cometary appearance of the object was confirmed by several other observers within hours.
A quick check of archived Catalina images of Scheila from October 18, November 2 and November 11 showed Scheila to look star-like, which is what asteroids look like from Earth. They just happen to be moving across the field of view in contrast to the fixed background stars. The image taken by Catalina on December 3rd shows some slight diffuseness and an increase in overall brightness. So, it appears this event began on or around December 3rd.
Upon hearing the news, there was some speculation that this might be evidence of an impact event. Had something crashed into asteroid Scheila? It seems unlikely, and this is a story we have heard before.
The asteroid discovered in 1979 and named 1979 OW7 was lost to astronomers for years and then recovered in 1996. It was subsequently renamed 1996 N2. That same year it was discovered to have a comet-like appearance, and many believed this was the signature of an impact between two asteroids. After years of inactivity 1996 N2 sprouted a tail again in 2002. One collision between two asteroids was unlikely enough. The odds of it happening again to the same object were essentially zero. What we had was a comet masquerading as an asteroid. This object is now known by its cometary name 133P/Elst-Pizarro, named after the two astronomers who discovered its initial cometary outburst.
The 2002 outburst and the discovery of more active asteroids showing mass-loss led to a paper (Hsieh and Jewitt 2006, Science, 312, 561-563) introducing an entirely new class of solar system objects, Main Belt Comets (MBC). MBCs look like comets because they show comae and have tails but they have orbits inside Jupiter’s orbit like main belt asteroids.
The most likely cause of the mass loss activity in MBCs is sublimation of water ice as the surface of the MBC is heated by the Sun. This is suggested most strongly by the behavior of the best-studied example, namely 133P/Elst-Pizarro. Its activity is recurrent, and it is strongest near and after perihelion, the point in its orbit nearest the Sun, like other comets.
MBCs are interesting to astronomers because they appear to be a third reservoir of comets in our solar system, distinct from the Oort cloud and Kuiper belt. Since we know of no way for these other reservoirs to have deposited comets in the inner solar system, the ice in MBCs probably has a different history than the ice in the outer comets. This allows researchers to study the differences in the Sun’s proto-planetary disk at three separate locations. This might lead to information on the Earth’s oceans, one of the continuing lines of investigation by solar system scientists.
Now it seems we have another MBC to add to the sample. And Scheila will probably be getting a new name soon. Asteroid (596) Scheila was discovered Feb. 21, 1906, by A. Kopff at Heidelberg. The 113Km in diameter ‘asteroid’ was named after an acquaintance, an English student at Heidelberg. In the future it will be called XXXP/Lawson or something similar, and Kopff’s Scheila will become just another footnote in the history of astronomical nomenclature.