An artists concept of the Phobos-Grunt Mission. Credit: Roscosmos
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Editor’s note: Dr. David Warmflash, principal science lead for the US team from the LIFE experiment on board the Phobos-Grunt spacecraft, provides an update on the mission for Universe Today.
It has been trapped in low Earth orbit for more than a month. So low is the orbit that it moves too fast to be contacted – unless controllers on the ground just happen to beam a signal at some unlikely angle. So short does its battery power last that it must be in sunlight while also in position to receive signals. Then, it must still have power to send telemetry back to the ground.
Even with these obstacles, Russia’s Phobos- Grunt probe did manage to communicate with the European Space Agency’s (ESA) antenna in Perth, Australia twice a couple of weeks ago, indicating that some of its systems were functioning. But subsequent attempts at communication have failed, despite the addition of ESA’s Canary Islands antenna at Maspalomas to the worldwide effort to reestablish control over the spacecraft.
Tracking of Grunt’s orbit has shown that its high point (apogee) and low point (perigee) continue to decrease, measuring about 289 kilometers and 203 kilometers in altitude, respectively, the last time I checked. Stories out of Russia in recent days describe how electrical cables found to be malfunctioning weeks before the launch were cut and connections re-soldered in a hurry to have the craft ready. Add to this the fact that the major sources on developments with the Grunt mission since its November 9 launch – Ria Novosti, the Russian Space Web, and ESA operations – all expect the craft to reenter Earth’s atmosphere in early January.
Taking all of this into account, it seems unlikely that Phobos-Grunt will ever respond to a signal again and say, “privyet’, much less turn on its engines and warp out of orbit. But there is an opportunity coming, a period when the odds that are stacked against the spacecraft may improve just a little.
Beginning Tuesday, December 13 at 17:00 universal time (UT) to Wednesday December 14, 23:00, Phobos-Grunt will be in sunlight throughout its entire orbit. It is not completely clear whether or not ESA will attempt to contact the probe during this period from Perth, or Maspalomas. Although attempts from Maspalomas were made throughout last week, the same attempts were scheduled to end on Friday, December 9. On the other hand, in a letter informing scientists participating in the mission that failure was the outcome, Phobos-Grunt science director, Lev Zelenyi, wrote: “Lavochkin Association specialists will continue their attempts to establish connection with the spacecraft and send commands until the very end of its existence.” Thus, despite the fact that the Russian Grunt team now is focused on the issue of reentry, we should not be surprised if they ask ESA to make one more attempt on Tuesday.
Will the greater than usual amount of sunlight allow the spacecraft’s communication system to work better than it usually does when it travels over tracking stations? Maybe yes, and maybe no. We should not get our hopes up that the craft will actually do anything but fall to Earth, and we’ve already discussed the possibility of the craft’s return capsule coming back in one piece.
Opportunity discovers Water related mineral vein at Endeavour Crater - November 2011. Opportunity rover discovered Gypsum at the Homestake mineral vein, while exploring around the base of Cape York ridge at the rim of Endeavour Crater. The vein is composed of calcium sulfate and indicates the ancient flow of liquid water at this spot on Mars. Opportunity drove North (ahead) from here in search of a sunny winter haven. Credit: NASA/JPL/Cornell/Kenneth Kremer/Marco Di Lorenzo
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NASA’s long lived Opportunity rover has discovered the most scientifically compelling evidence yet for the flow of liquid water on ancient Mars. The startling revelation comes in the form of a bright vein of the mineral gypsum located at the foothills of an enormous crater named Endeavour, where the intrepid robot is currently traversing. See our mosaic above, illustrating the exact spot.
Update: ‘Homestake’ Opportunity Mosaic above has just been published on Astronomy Picture of the Day (APOD) – 12 Dec 2011 (by Ken Kremer and Marco Di Lorenzo)
Researchers trumpeted the significant water finding this week (Dec. 7) at the annual winter meeting of the American Geophysical Union (AGU) in San Francisco.
“This gypsum vein is the single most powerful piece of evidence for liquid water at Mars that has been discovered by the Opportunity rover,” announced Steve Squyres of Cornell University, Ithaca, N.Y., Principal Investigator for Opportunity, at an AGU press conference.
The light-toned vein is apparently composed of the mineral gypsum and was deposited as a result of precipitation from percolating pools of liquid water which flowed on the surface and subsurface of ancient Mars, billions of years ago. Liquid water is an essential prerequisite for life as we know it.
“This tells a slam-dunk story that water flowed through underground fractures in the rock,” said Squyres. “This stuff is a fairly pure chemical deposit that formed in place right where we see it. That can’t be said for other gypsum seen on Mars or for other water-related minerals Opportunity has found. It’s not uncommon on Earth, but on Mars, it’s the kind of thing that makes geologists jump out of their chairs.”
'Homestake' Vein in Color and Close-up
This color view of a mineral vein called "Homestake" was taken by the panoramic camera (Pancam) on NASA's Mars Exploration Rover Opportunity. The vein is about the width of a thumb and about 18 inches (45 centimeters) long. Opportunity examined it in November 2011 and found it to be rich in calcium and sulfur, possibly the calcium-sulfate mineral gypsum.
The light-toned vein is informally named “Homestake”, and was examined up close by Opportunity’s cameras and science instruments for several weeks this past month in November 2011, as the rover was driving northwards along the western edge of a ridge dubbed ‘Cape York’ – which is a low lying segment of the eroded rim of Endeavour Crater.
Veins are a geologic indication of the past flow of liquid water
Opportunity just arrived at the rim of the 14 mile (22 kilometere) wide Endeavour Crater in mid-August 2011 following an epic three year trek across treacherous dune fields from her prior investigative target at the ½ mile wide Victoria Crater.
“It’s like a whole new mission since we arrived at Cape York,” said Squyres.
‘Homestake’ is a very bright linear feature.
“The ‘Homestake’ vein is about 1 centimeter wide and 40 to 50 centimeters long,” Squyres elaborated. “It’s about the width of a human thumb.”
Opportunity's Approach to 'Homestake'
This view from the front hazard-avoidance camera on NASA's Mars Exploration Rover Opportunity shows the rover's arm's shadow falling near a bright mineral vein informally named Homestake. The vein is about the width of a thumb and about 18 inches (45 centimeters) long. Opportunity examined it in November 2011 and found it to be rich in calcium and sulfur, possibly the calcium-sulfate mineral gypsum. Opportunity took this image on Sol 2763 on Mars (Nov. 7, 2011). Credit: NASA/JPL-Caltech
Homestake protrudes slightly above the surrounding ground and bedrock and appears to be part of a system of mineral veins running inside an apron (or Bench) that in turn encircles the entire ridge dubbed Cape York.
In another first, no other veins like these have been seen by Opportunity throughout her entire 20 miles (33 kilometers) and nearly eight year long Martian journey across the cratered, pockmarked plains of Meridiani Planum, said Squyres.
The veins have also not been seen in the higher ground around the rim at Endeavour crater.
“We want to understand why these veins are in the apron but not out on the plains,” said the mission’s deputy principal investigator, Ray Arvidson, of Washington University in St. Louis. “The answer may be that rising groundwater coming from the ancient crust moved through material adjacent to Cape York and deposited gypsum, because this material would be relatively insoluble compared with either magnesium or iron sulfates.”
Opportunity was tasked to engage her Microscopic Imager and Alpha Particle X-ray Spectrometer (APXS) mounted on the terminus of the rover’s arm as well as multiple filters of the mast mounted Panoramic Camera to examine ‘Homestake’.
“The APXS spectrometer shows ’Homestake’ is chock full of Calcium and Sulfur,” Squyres gushed.
Microscopic Close-up View of 'Homestake' Vein
This close-up view of a mineral vein called Homestake comes from the microscopic imager on Opportunity. The vein is about the width of a thumb and about 18 inches (45 centimeters) long. Opportunity examined it in November 2011 and found it to be rich in calcium and sulfur, possibly the calcium-sulfate mineral gypsum. Homestake is near the edge of the "Cape York" segment of the western rim of Endeavour Crater. This view blends three exposures taken by the microscopic imager during the 2,765th and 2,766th Martian days, or sols, of Opportunity's career on Mars (Nov. 3 and 4, 2011). Credit: NASA/JPL-Caltech/Cornell/USGS
The measurements of composition with the APXS show that the ratio points to it being relatively pure calcium sulfate, Squyres explained. “One type of calcium sulfate is gypsum.”
Calcium sulfate can have varying amounts of water bound into the minerals crystal structure.
The rover science team believes that this form of gypsum discovered by Opportunity is the dihydrate; CaSO4•2H2O. On Earth, gypsum is used for making drywall and plaster of Paris.
The gypsum was formed in the exact spot where Opportunity found it – unlike the sulfate minerals previously discovered which were moved around by the wind and other environmental and geologic forces.
“There was a fracture in the rock, water flowed through it, gypsum was precipitated from the water. End of story,” Squyres noted. “There’s no ambiguity about this, and this is what makes it so cool.”
At Homestake we are seeing the evidence of the ground waters that flowed through the ancient Noachian rocks and the precipitation of the gypsum, which is the least soluble of the sulfates, and the other magnesium and iron sulfates which Opportunity has been driving on for the last 8 years.
Opportunity Traverse Map 2004 to 2011
Traverse map showing the 8 Year Journey of Opportunity from Eagle Crater landing site Sol 1 (Jan. 24, 2004) to Sol 2775 (November 2011). Map shows rover location around Homestake water related mineral on Sol 2763 (November 2011) at Cape York ridge at Endeavour Crater rim. Endeavour Crater is 14 miles or 22 kilometers in diameter. Opportunity has driven more than 21 miles (34 km).
Credit: NASA/JPL/Cornell/Marco Di Lorenzo/Kenneth Kremer
“Here, both the chemistry, mineralogy, and the morphology just scream water,” Squyres exclaimed. “This is more solid than anything else that we’ve seen in the whole mission.”
It’s inconceivable that the vein is something else beside gypsum, said Squyres.
As Opportunity drove from the plains of Meridiani onto the rim of Endeavour Crater and Cape York, it crossed a geologic boundary and arrived at a much different and older region of ancient Mars.
The evidence for flowing liquid water at Endeavour crater is even more powerful than the silica deposits found by Spirit around the Home Plate volcanic feature at Gusev Crater a few years ago.
“We will look for more of these veins in the [Martian] springtime,” said Squyres.
If a bigger, fatter vein can be found, then Opportunity will be directed to grind into it with her still well functioning Rock Abrasion Tool, or RAT.
Homestake was crunched with the wheels – driving back and forth over the vein – to break it up and expose the interior. Opportunity did a triple crunch over Homestake, said Arvidson.
Homestake was found near the northern tip of Cape York, while Opportunity was scouting out a “Winter Haven” location to spend the approaching Martian winter.
Arvidson emphasized that the team wants Opportunity to be positioned on a northerly tilted slope to catch the maximum amount of the sun’s rays to keep the rover powered up for continuing science activities throughout the fast approaching Martian winter.
“Martian winter in the southern hemisphere starts on March 29, 2012. But, Solar power levels already begin dropping dramatically months before Martian winter starts,” said Alfonso Herrera to Universe Today, Herrera is a Mars rover mission manager at NASA’s Jet Propulsion Laboratory in Pasadena, Calif.
“Opportunity is in excellent health,” said Bruce Banerdt, the Project Scientist for the Mars rover mission at JPL.
“This has been a very exciting time. We’ll head back south in the springtime and have a whole bunch of things to do with a very capable robot,” Squyres concluded.
'Botany Bay' and 'Cape York' with Vertical Exaggeration
This graphic combines a perspective view of the "Botany Bay" and "Cape York" areas of the rim of Endeavour Crater on Mars, and an inset with mapping-spectrometer data. Major features are labeled. In the perspective view, the landscape's vertical dimension is exaggerated five-fold compared with horizontal dimensions. NASA's Mars Exploration Rover Opportunity examined targets in the Cape York area during the second half of 2011. The perspective view was generated by producing an elevation map from a stereo pair of images from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter, then draping one of the HiRISE images over the elevation model. The inset presents data from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) instrument on the Mars Reconnaissance Orbiter. In this CRISM observation, taken on March 29, 2011 Thermal inertia estimates from observations by the Thermal Emission Imaging System on NASA's Mars Odyssey orbiter indicate that Botany Bay is a region with extensive outcrop exposures. Credit: NASA/JPL-Caltech/UA/JHUAPL
Meanwhile, NASA’s next leap in exploring potential Martian habitats for life – the car sized Curiosity Mars Science Lab rover – is speeding towards the Red Planet.
Read Ken’s continuing features about Opportunity starting here:
Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment (HiRISE) camera captured this image of Phoenix hanging from its parachute as it descended to the Martian surface. Credit: NASA/JPL/University of Arizona.
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Remember this amazing image from 2008? The HiRISE (High Resolution Imaging Science Experiment) camera on the Mars Reconnaissance Orbiter captured the Phoenix lander descending on a parachute to land on Mars’ north polar region. MRO will attempt a repeat performance in August of 2012 when the Mars Science Laboratory rover “Curiosity” will be landing in Gale Crater on Mars. Capturing this event would be epic, especially with MSL’s unique “skycrane” landing system.
“Yes, MRO is planning to image the descent of MSL with both HiRISE and CTX (Context Camera),” Alfred McEwen, HiRISE principal investigator told Universe Today. “For Phoenix we got a bit lucky with HiRISE in terms of the geometry, giving us a high probability of success. It may not work out so well for MSL. What I’d really like is to capture the rover hanging from the skycrane, but the timing may be difficult.”
Again, the word here is epic.
So, how challenging is it for a spacecraft orbiting Mars to try and track another spacecraft coming in?
“If we were not to do anything, the Mars’ orbiting spacecraft may be on the other side of the planet,” said MSL navigation team chief Tomas Martin-Mur, during an interview with UT. “So as soon as we launch, we tell the other spacecraft where we are going to be by the time of entry so they can change their orbits over time, so they will be flying overhead as MSL approaches the planet.”
The orbiters – which also includes NASA’s Mars Odyssey and ESA’s Mars Express – will have to do special maneuvers to be aligned in just the right place – nearby to MSL’s point of entry into Mars’ atmosphere — and they may even have to change the plane of their orbit.
This artist's concept shows the sky crane maneuver during the descent of NASA's Curiosity rover to the Martian surface. Credit: NASA/JPL-Caltech.
“The other thing that we’ll need them to do is to point their UHF antennas towards MSL,” Martin-Mur said. “Normally their antennas will be pointed to take pictures, but they will have to go to a special attitude to point to MSL. This will enable them to try — like they did with Phoenix — to take a picture of the spacecraft as it is coming down to the planet. We are hoping to see the parachute deployed and maybe more.”
“That was a great picture for Phoenix, and we will attempt to repeat that,” Martin-Mur added.
While Odyssey and Mars Express’ cameras may not have the resolving power to capture such an image, MRO’s powerful HiRISE camera does. However it has a narrower field of view, so as much skill and planning as this requires, the team will need a little luck, too. But there’s also the CTX.
“CTX has a much larger field of view and will likely capture it,” McEwen said, “but at 20X lower resolution than HiRISE, which should still be good enough to detect the parachute.”
Here’s a preview of what MSL will be going through during the perilous entry descent and landing:
Coronal Mass Ejection as viewed by the Solar Dynamics Observatory on June 7, 2011. A similar type of outburst triggered aurorae during a strong geomagnetic storm in February 1872. Image Credit: NASA/SDO
[/caption]According to a new set of NASA computer simulations, solar storms and Coronal Mass Ejections (CMEs) can erode the lunar surface. Researchers speculate that not only can these phenomena erode the lunar surface, but could also be a cause of atmospheric loss for planets without a global magnetic field, such as Mars.
A team led by Rosemary Killen at NASA’s Goddard Space Flight Center, has written papers exploring different aspects of these phenomena and will appear in an issue of the Journal of Geophysical Research Planets. The team’s research was also presented earlier this week during the fall meeting of the American Geophysical Union.
What are CME’s? Corona Mass Ejections are intense outbursts of the Sun’s usually normal solar wind which consists of electrically charged particles (plasma). CME’s blow outward from the surface of the Sun at speeds in excess of 1.6 million kilometers per hour into space and can contain over a billion tons of plasma in a cloud larger than Earth.
Our Moon has the faintest traces of an atmosphere, which is technically referred to as an exosphere. The lack of any significant atmosphere, combined with the lack of a magnetic field, makes the lunar surface vulnerable to the effects of CME’s.
William Farrell, DREAM (Dynamic Response of the Environment at the Moon) team lead at NASA Goddard, remarked, “We found that when this massive cloud of plasma strikes the Moon, it acts like a sandblaster and easily removes volatile material from the surface. The model predicts 100 to 200 tons of lunar material – the equivalent of 10 dump truck loads – could be stripped off the lunar surface during the typical 2-day passage of a CME.”
While CME’s have been extensively studied, Farrell’s research is the first of its kind that attempts to predict the effects of a CME on the Moon. “Connecting various models together to mimic conditions during solar storms is a major goal of the DREAM project” added Farrell.
When intense heat or radiation is applied to a gas, the electrons can be removed, turning the atoms into ions. This process is referred to as “ionization”, and creates the fourth form of matter, known as plasma. Our Sun’s intense heat and radiation excites gaseous emissions, thus creating a solar wind plasma of charged particles. When plasma ions eject atoms from a surface, the process is called “sputtering”.
The lead author of the research paper Rosemary Killen described this phenomenon: “Sputtering is among the top five processes that create the Moon’s exosphere under normal solar conditions, but our model predicts that during a CME, it becomes the dominant method by far, with up to 50 times the yield of the other methods.”
Images from computer simulations of the lunar calcium exosphere during a CME (left) and the slow solar wind (right). Red and yellow indicate a relatively high abundance of calcium atoms while blue, purple, and black indicate a low abundance. The CME produces a much denser exosphere than the slow solar wind. Image Credit: NASA / Johns Hopkins University
In an effort to better test the team’s predictions, studies will be performed using NASA’s Lunar Atmosphere And Dust Environment Explorer (LADEE). Scheduled to launch in 2013 and orbit the Moon, the team is confident that the strong sputtering effect will send atoms from the lunar surface to LADEE’s orbital altitude (20 to 50 km).
Farrell also added, “This huge CME sputtering effect will make LADEE almost like a surface mineralogy explorer, not because LADEE is on the surface, but because during solar storms surface atoms are blasted up to LADEE.”
Affecting more than just our Moon, solar storms also affect Earth’s magnetic field and are the root cause of the Northern and Southern lights (aurorae). The effect solar storms have on Mars is a bit more significant, due in part to the Red Planet’s lack of a planet-wide magnetic field. It is widely theorized that this lack of a magnetic field allows the solar wind and CME’s to erode the martian atmosphere. In late 2013, NASA will launch the Mars Atmosphere and Volatile Evolution (MAVEN) mission. The goal of MAVEN is to orbit Mars and help researchers better understand how solar activity, including CMEs, affects the atmosphere of the red planet.
Artist concept of Russia’s Phobos-Grunt spacecraft. Credit Roscosmos.
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Editor’s note: Dr. David Warmflash, principal science lead for the US team from the LIFE experiment on board the Phobos-Grunt spacecraft, provides an update on the mission for Universe Today.
Russia’s Phobos-Grunt spacecraft is in no better position than it was a month ago, when it reached low Earth orbit on November 9 yet failed to ignite the upper stage engine that was to propel it to Phobos, the larger of Mars’ two small moons. Indeed, with an orbit measuring 204.823 kilometers at perigee (the low point) and 294.567 kilometers at apogee as of today, the spacecraft is well on its well to a fiery reentry through Earth’s atmosphere in early January if it cannot be rescued in the intervening time. But the Russian space agency, Roscosmos, is not ready to give up on the probe yet, and have asked ESA to resume trying to contact Phobos-Grunt.
Despite success in contacting Grunt and getting it to send telemetry two weeks ago using a modified antenna in Perth Australia, subsequent attempts to command the spacecraft to boost her orbit failed.
Then last week, after modifying another antenna, this one in Maspalomas on the Canary Islands, the European Space Agency (ESA) announced that efforts to track and communicate with the spacecraft would end. As a result, any remaining hope that the craft might at least be boosted to a more stable orbit to allow for diagnoses and eventual repair faded away.
Maspalomas station hosts a 15-metre antenna with reception in S- and X-Band and transmission in S-band. It is located on the campus of the Instituto Nacional de Tecnica Aerospacial (INTA), in the southern part of the Canary Islands' Gran Canaria, at Montaña Blanca.Credit: ESA
But, in response to requests from the Russian Space Agency (Roscosmos), ESA now has decided to renew tracking and communications efforts from the Maspalomas station. Located off of the northwest coast of Africa, Maspalomas is well-situated with respect to Phobos-Grunt’s course around Earth. Since fewer communication attempts have been made from Maspalomas as compared with Perth, ESA and Roscosmos may be thinking that not all potential tricks to get the geometry right have been exhausted. Thus, new attempts to hail the unpiloted science probe began on Monday and will continue through Friday, December 9th. Presumably, ESA would continue to support the mission beyond Friday, if anything happens suggesting that Phobos-Grunt has received the instructions and is capable of responding, even in part.
Designed to land on the surface of Phobos, the Grunt spacecraft carries about 50 kilograms of scientific equipment built to make celestial and geophysical measurements, and to conduct mineralogical and chemical analysis of the regolith (crushed rock and dust) of the tiny moon. The chemical analysis that is to be conducted includes a search for organic matter, the building material for life. Studies to be conducted on the Phobosian surface potentially could elucidate the origins of Phobos and the other Martian moon, Deimos. Additionally, the presence of organic matter on Phobos would suggest that the surface of Mars itself contains organics. Despite findings by NASA’s Viking landing crafts in the 1970s suggesting that the surface of Mars lacks organic material, studies by more recent probes suggest that compounds known as perchlorates –detected by Viking but dismissed as contaminants from Earth– may have been native to Mars. This issue will be investigated further when NASA’s Curiosity rover arrives on the Red Planet several months from now.
The Planetary Society’s Living Interplanetary Flight Experiment (LIFE) capsule, on board the Phobos-Grunt spacecraft. Credit:The Planetary Society
Grunt also carries Yinhou-1, a Chinese probe that is to orbit Mars for 2 years. After releasing Yinhou-1 into Mars orbit and landing on Phobos, Grunt is designed to launch a return capsule, carrying a 200 gram sample of regolith back to Earth. Also traveling within the return capsule is the Planetary Society’s Living Interplanetary Flight Experiment (LIFE), designed to investigate how readily living forms could spread between neighboring planets.
Although prospects for this ambitious mission still look bleak, Alexander Zakharov of Russia’s Space Research Institute, who was instrumental in getting the LIFE experiment onto the Grunt mission, has suggested that a new Grunt mission might be launched, presumably on time for the next launch window to Mars, which opens in approximately 26 months.
Meanwhile, today, NASA’s space debris chief said that Phobos-Grunt would pose no threat to Earth when it reenters the atmosphere.
'Rainbow-Colored Palette' of Southern Hemisphere of Asteroid Vesta from NASA Dawn Orbiter. This mosaic using color data obtained by the framing camera aboard NASA's Dawn spacecraft shows Vesta's southern hemisphere in false color, centered on the Rheasilvia impact basin, about 290 miles (467 kilometers) in diameter with a central mound reaching about 14 miles (23 kilometers) high. The black hole in the middle is data that have been omitted due to the angle between the sun, Vesta and the spacecraft. The green areas suggest the presence of the iron-rich mineral pyroxene or large-sized particles. This mosaic was assembled using images obtained during Dawn's approach to Vesta, at a resolution of 480 meters per pixel. The German Aerospace Center and the Max Planck Institute for Solar System Research provided the Framing Camera instrument and funding as international partners on the mission team. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
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The giant Asteroid Vesta is among the most colorful bodies in our entire solar system and it appears to be much more like a terrestrial planet than a mere asteroid, say scientists deciphering stunning new images and measurements of Vesta received from NASA’s revolutionary Dawn spacecraft. The space probe only recently began circling about the huge asteroid in July after a four year interplanetary journey.
Vesta is a heavily battered and rugged world that’s littered with craters and mysterious grooves and troughs. It is the second most massive object in the Asteroid Belt and formed at nearly the same time as the Solar System some 4.5 Billion years ago.
“The framing cameras show Vesta is one of the most colorful objects in the solar system,” said mission scientist Vishnu Reddy of the Max Planck Institute for Solar System Research in Katlenburg-Lindau, Germany. “Vesta is unlike any other asteroid we have visited so far.”
Scientists presented the new images and findings from Dawn at the American Geophysical Union meeting this week in San Francisco.
Comparative View of Terrains on Vesta - Oppia Crater
This image of Oppia Crater combines two separate views of the giant asteroid Vesta obtained by Dawn's framing camera. The far-left image uses near-infrared filters where red is used to represent 750 nanometers, green represents 920 nanometers and blue represents 980 nanometers. The image on the right is an image with colors assigned by scientists, representing different rock or mineral types on Vesta. The data reveal a world of many varied, well-separated layers and ingredients. The reddish color suggests a steep visible spectral slope, and areas of fresh landslides in the inner walls of the crater show deeper green colors. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
“Vesta is a transitional body between a small asteroid and a planet and is unique in many ways,” Reddy said. “We do not know why Vesta is so special.”
Although many asteroids look like potatoes, Reddy said Vesta reminds him more of an avocado.
Asteroid Vesta is revealed as a ‘rainbow-colored palette’ in a new image mosaic (above) showcasing this alien world of highly diverse rock and mineral types of many well-separated layers and ingredients.
Researchers assigned different colors as markers to represent different rock compositions in the stunning new mosaic of the asteroid’s southern hemisphere.
The green areas in the mosaic suggest the presence of the iron-rich mineral pyroxene or large-sized particles, according to Eleonora Ammannito, from the Visible and Infrared (VIR) spectrometer team of the Italian Space Agency. The ragged surface materials are a mixture of rapidly cooled surface rocks and a deeper layer that cooled more slowly.
What could the other colors represent?
“The surface is very much consistent with the variability in the HED (Howardite-Eucritic-Diogenite) meteorites,” Prof. Chris Russell, Dawn Principal Investigator (UCLA) told Universe Today in an exclusive interview.
“There is Diogenite in varying amounts.”
“The different colors represent in part different ratios of Diogenite to Eucritic material. Other color variation may be due to particle sizes and to aging,” Russell told me.
No evidence of volcanic materials has been detected so far, said David Williams, Dawn participating scientist of Arizona State University, Tucson. Fresh Impact Craters on Asteroid Vesta
The fresh impact craters in this view are located in the south polar region, which has been partly covered by landslides from the adjacent crater. This would suggest that a layer of loose material covers the Vesta surface. This image combines two separate views of the giant asteroid Vesta obtained by Dawn’s framing camera. The far-left image uses near-infrared filters where red is used to represent 750 nanometers, green represents 920 nanometers and blue represents 980 nanometers. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
Before Dawn arrived, researchers expected to observe indications of volcanic activity. So, the lack of findings of volcanism is somewhat surprising. Williams said that past volcanic activity may be masked due to the extensive battering and resultant mixing of the surface regolith.
“More than 10,000 high resolution images of Vesta have been snapped to date by the framing cameras on Dawn,” Dr. Marc Rayman told Universe Today. Rayman is Dawn’s Chief Engineer from NASA’s Jet Propulsion Lab (JPL) in Pasadena, Calif.
Dawn will spend a year in orbit at Vesta and investigate the asteroid at different altitudes with three on-board science instruments from the US, Germany and Italy.
The probe will soon finish spiraling down to her lowest mapping orbit known as LAMO (Low Altitude Mapping Orbit), approximately 130 miles (210 kilometers) above Vesta’s surface.
“Dawn remains on course to begin its scientific observations in LAMO on December 12,” said Rayman.
The German Aerospace Center and the Max Planck Institute for Solar System Research provided the Framing Camera instrument and funding as international partners on the mission team. The Visible and Infrared Mapping camera was provided by the Italian Space Agency.
In July 2012, Rayman and the engineering team will fire up Dawn’s ion propulsion system, break orbit and head to Ceres, the largest asteroid and what a number of scientists consider to be a planet itself.
Ceres is believed to harbor thick caches of water ice and therefore could be a potential candidate for life.
Southern Hemisphere of Vesta -Rheasilvia and Older Basin
Colorized shaded-relief map showing location of 375-kilometer-wide Older impact basin that is overlapping with the more recent 500 km (300 mi) wide Rheasilvia impact structure at asteroid Vesta’s South Pole. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDAAsteroid Vesta from Dawn - Exquisite Clarity from a formerly Fuzzy Blob
NASA's Dawn spacecraft obtained this image of the giant asteroid Vesta with its framing camera on July 24, 2011. It was taken from a distance of about 3,200 miles (5,200 kilometers). Before Dawn, Vesta was just a fuzzy blob in the most powerful telescopes. Dawn entered orbit around Vesta on July 15, and will spend a year orbiting the body before firing up the ion propulsion system to break orbit and speed to Ceres, the largest Asteroid. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
Read continuing features about Dawn by Ken Kremer starting here:
The Voyager 1 spacecraft has started to transverse what JPL has dubbed as a "cosmic purgatory" between our solar system - and interstellar space. Image Credit: NASA/JPL
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Voyager 1 is in uncharted territory. The long-lived spacecraft has entered a new region of space that lies between where our solar system ends and where interstellar space begins. This area is not a place of sightseeing however, as a NASA press release referred to it as a kind of “cosmic purgatory.”
Here, the solar winds ebb somewhat, the magnetic field increases and charged particles from within our solar system – is leaking out into interstellar space. This data has been compiled from information received from Voyager 1 over the course of the last year.
The Voyager spacecraft's compliment of scientific instruments have provided scientists back on Earth with information about what the space environment at the fringes of our sun's influence is truly like. Image Credit: NASA/JPL - Caltech
“Voyager tells us now that we’re in a stagnation region in the outermost layer of the bubble around our solar system,” said Ed Stone, Voyager project scientist at the California Institute of Technology in Pasadena. “Voyager is showing that what is outside is pushing back. We shouldn’t have long to wait to find out what the space between stars is really like.”
Despite the fact that Voyager 1 is approximately 11 billion miles (18 billion kilometers) distant from the sun – it still has not encounter interstellar space. The information that scientists have gleaned from the Voyager 1 spacecraft indicates that the spacecraft is still located within the heliosphere. The heliosphere is a “bubble” of charged particles that the sun blows around itself and its retinue of planets.
Voyager 1 has traveled far past the realm of the gas or even ice giants and is now in uncharted territory where scientists are learning more and more about the dynamic environment at the far-flung edges of our solar system. Image Credit: NASA/JPL - Caltech
The latest findings were made using Voyager’s Low Energy Charged Particle instrument, Cosmic Ray Subsystem and Magnetometer.
Experts are not certain how long it will take the Voyager 1 spacecraft to finally breach this bubble and head out into interstellar space. Best estimates place the length of time when this could happen anywhere from the next few months – to years. These findings counter findings announced in April of 2010 that showed that Voyager 1 had essentially crossed the heliosphere boundary. The discoveries made during the past year hint that this region of space is far more dynamic than previously thought.
Voyager 1 has entered into a region of space between the sun's influence and the beginning of interstellar space that NASA has dubbed the "stagnation region." Image Credit: NASA/JPL - Caltech
The magnetometer aboard Voyager 1 has picked up an increase in the intensity of the magnetic field located within this “stagnation field.” Essentially the inward pressure from interstellar space is compressing the magnetic field to twice its original density. The spacecraft has also detected a 100-fold increase in the intensity of high-energy electrons diffusing into our solar system from outside – this is yet another indicator that Voyager 1 is approaching the heliosphere.
The interplanetary probe was launched from Cape Canaveral Air Force Station’s Space Launch Complex 41 (SLC-41) on Sept. 5, 1977, Voyager 1’s sister ship, Voyager 2 is also in good health and is about 9 billion miles (15 billion kilometers) from the sun (it too was launched in 1977). The spacecraft itself was built by NASA’s Jet Propulsion Laboratory in Pasadena, Calif.
“Voyager is a mission of discovery and it’s at the edge of the solar system still making discoveries,” said Stone said. “The stagnation is the latest in the whole journey of discovery. We are all excited because we believe it means we’re getting very close to boundary of heliosphere and the entry into interstellar space.”
Both of the Voyager spacecraft were thrust to orbit by the powerful Titan boosters - and both in the same year - 1977. Photo Credit: NASA
Chris Ferguson, the commander of the final mission of the shuttle program, STS-135 has announced that he will leave the space agency. Photo Credit: NASA.gov
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On Dec. 9, 2011, NASA will witness the departure of the astronaut who served as commander for the final space shuttle mission STS-135. Chris Ferguson has announced his plans to retire from the space agency so that he can enter the private sector. With Ferguson’s departure, all of the commanders who flew the final three shuttle missions have left or will be departing NASA.
With no defined human space flight mission objectives in place and with the only ride to space currently being Russia’s Soyuz Spacecraft many astronauts are leaving the agency for other prospects. The space agency is losing an astronaut at the rate of one astronaut every two months. As of Dec. 9 NASA will have 58 astronauts in its active roster.
Ferguson has flown into space, twice on space shuttle Atlantis, logging over 40 days in space. Photo Credit: NASA.gov
Ferguson is a retired U.S. Navy captain – his command of Atlantis’ final flight marked his third trip into space. The 13-day mission was a resupply flight to the International Space Station and saw some 10,000 pounds of supplies and spare parts delivered to the orbiting outpost. With the final landing, conducted on July 21, 2011, Ferguson and his crew wrapped up the shuttle program’s 30 year history.
“Chris has been a great friend, a tremendous professional and an invaluable asset to the NASA team and the astronaut office,” said Peggy Whitson, chief of the Astronaut Office. “His exceptional leadership helped ensure a perfect final flight of the space shuttle,
a fitting tribute to the thousands who made the program possible.”
Ferguson (third from left) has opted to leave NASA to pursue a job in the private sector. His departure comes at a time when NASA is losing many of its experienced space flyers. Image Credit: NASA.gov
Ferguson’s very first mission, STS-115, was also on Atlantis. He served as the pilot on this mission which took place in 2006 and delivered the P3 and P4 truss segments to the space station. His next shuttle flight was STS-126 on shuttle Endeavour, this mission saw water reclamation and habitation systems transported to the ISS (as well as conducting a crew swap out). Ferguson has over 40 days of space flight experience.
Ferguson joined NASA’s astronaut corps in 1998. Upon his completion of initial astronaut training, he performed technical duties related to the shuttle’s main engines (SSMEs), the orbiter’s large, orange external tank, solid rocket boosters (SRBs) as well as software utilized on the shuttles. Before he was given the nod to be the commander of STS-135, Ferguson was the deputy chief of the Astronaut Office at NASA’s Johnson Space Center located in Houston, Texas.
“Chris has been a true leader at NASA,” said NASA Administrator Charles Bolden, “not just as a commander of the space shuttle, but also as an exemplary civil servant, a distinguished Navy officer and a good friend. I am confident he will succeed in his next career as he brings his skill and talents to new endeavors.”
Chris Ferguson has served NASA in a variety of roles since being accepted as an astronaut in 1998. Photo Credit: NASA.gov
The Orbital Test Vehicle or OTV has been launched twice by the United States Air Force. There is one currently on orbit that has had its mission extended - past the officially stated endurance time that the USAF had previously announced. Photo Credit: USAF
Video provided courtesy of United Launch Alliance
The United States Air Force’s second flight of the X-37B – is headed into extra innings. Known as the Orbital Test Vehicle 2 (OTV-2) this robotic mini space shuttle launched from Cape Canaveral Air Force Station’s Space Launch Complex 41 (SLC-41) on Mar. 5, 2011. Although the U.S. Air Force has kept mum regarding details about the space plane’s mission – it has announced that the OTV-2 has exceeded its endurance limit of 270 days on orbit as of the end of November.
The OTV is launched atop a United Launch Alliance (ULA) Atlas V 501 rocket. The space plane is protected within a fairing until it reaches orbit. After separation, the diminutive shuttle begins its mission.
OTV mission USA-226, as it is officially known, is by all accounts going smoothly and the spacecraft is reported to be in good health. The U.S. Air Force has not announced when OTV-2 will be directed to land.
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The fact that the space plane will continue to orbit beyond what its stated limits are highlights that the OTV has greater capabilities than what was officially announced. The first OTV flight launched in April of 2011 and landed 224 days later at Vandenberg Air Force Base in California. The U.S. Air Force is undoubtedly being more judicious with fuel stores on board the robotic spacecraft, allowing for a longer duration flight.
Much like NASA’s retired fleet of space shuttle orbiters, the OTV has a payload bay that allows for payloads and experiments to be conducted on-orbit. What payloads the U.S. Air Force has had on either mission – remains a secret.
Boeing has announced that the X-37B could be modified to conduct crewed missions to and from orbit. Tentatively named the X-37C, this spacecraft would be roughly twice the size of its unmanned cousin. If this variant goes into service it would be used to transport astronauts to and from the orbiting International Space Station (ISS).
OTV USA-226 launched on Mar. 5, 2011 and has helped prove out the mini space plane's design. Photo Credit: Alan Walters/awaltersphoto.com
The X-37B has become a bit controversial of late. Members of the Chinese press have stated that the space plane raises concerns of an arms race in space. Xinhua News Agency and China Daily have expressed concern that the OTVs could be used to deliver weapons to orbit. The Pentagon has flatly denied these allegations. The clandestine nature of these flights have led to a wide variety of theories as to what the OTVs have been used to ferry to orbit.
Curiosity Mars Science Laboratory Spacecraft During Cruise. Artist's concept of Curipsity during its cruise phase between launch on Nov. 26, 2011 and final approach to Mars in August 2012. The spacecraft includes a disc-shaped solar powered cruise stage (on the left) attached to the aeroshell (right). Curiosity and the descent stage are tucked inside the aeroshell. Along the way to Mars, the cruise stage will perform several trajectory correction maneuvers to adjust the spacecraft's path toward its final, precise landing site on Mars. Credit: NASA/JPL-Caltech
For a birds-eye view of where it all started, watch the cool close-up launch video, below taken from within the Atlas pad security fence.
Indeed the launch precision was so good that mission controllers at NASA’s Jet Propulsion Lab in Pasadsena, Calif., have announced they postponed the first of six planned course correction burns for the agency’s newest Mars rover by at least a month. The firing had been planned for some two weeks after liftoff.
Curiosity is merrily sailing on a 254 day and 352-million-mile (567-million-kilometer) interplanetary flight from the Earth to Mars that will culminate on August 6, 2012 with a dramatic first-of-its-kind precision rocket powered touchdown inside Gale Crater.
“This was among the most accurate interplanetary injections ever,” said Louis D’Amario of NASA’s Jet Propulsion Laboratory, Pasadena, Calif. He is the mission design and navigation manager for the Mars Science Laboratory.
Video Caption: View from inside the Pad 41 Security Fence at Cape Canaveral. Shot by a Canon 7D still camera during the launch of the Atlas V rocket carrying the MSL Curiosity rover to Mars. Thanks to a sound trigger my camera started firing at three frames per second from just after main engine ignition up until the exhaust plume finally envelops the camera and deadens all sound around it. The frames have been slowed down quite a bit for dramatic effect. Enjoy seeing what it is like for us media personnel who set out our remote cameras for launches at Kennedy Space Center and Cape Canaveral, Florida. Credit: Chase Clark/shuttlephotos.com
As of midday Friday, Dec. 2, the spacecraft had already traveled 10.8 million miles (17.3 million kilometers) and is moving at 7,500 mph (12,000 kilometers per hour) relative to Earth and at 73,800 mph (118,700 kilometers per hour) relative to the sun.
An interesting fact is that engineers deliberately planned the spacecraft’s initial trajectory to miss Mars by about 35,000 miles (56,400 kilometers) so that the Centaur upper stage does not hit Mars by accident. Both Centaur and Curiosity are currently following the same trajectory through the vast void of space and the actual trajectory puts them on course to miss Mars by about 38,000 miles (61,200 kilometers).
The Centaur has not been thoroughly cleaned of earthly microbes in the same way as Curiosity – and therefore cannot be permitted to impact the Martian surface and potentially contaminate the very studies Curiosity seeks to carry out in searching for the “Signs of Life”.
For the 8.5 month voyage to Mars, Curiosity and the rocket powered descent stage are tucked inside an aeroshell and are attached to the huge solar powered cruise stage.
Deceleration of Mars Science Laboratory in Martian Atmosphere
Artist's Concept depicts the interaction of NASA's Mars Science Laboratory spacecraft with the upper atmosphere of Mars during the entry, descent and landing (EDL) of the Curiosity rover onto the Martian surface. EDL begins when the spacecraft reaches the top of Martian atmosphere, about 81 miles (131 kilometers) above the surface of the Gale crater landing area, and ends with the rover safe and sound on the surface of Mars some 7 minutes later. During EDL, the spacecraft decelerates from a velocity of about 13,200 miles per hour (5,900 meters per second) at the top of the atmosphere, to stationary on the surface. Credit: NASA/JPL-Caltech
The cruise stage is rotating at 2.05 rounds per minutes and is continuously generating electric power – currently about 800 watts – from the gleaming solar arrays. It also houses eight miniature hydrazine fueled thrusters. The propellant is stored inside titanium tanks.
Atlas V rocket and Curiosity Mars rover poised at Space Launch Complex 41 at Cape Canaveral, Florida prior to Nov. 26, 2011 liftoff. Credit: Ken Kremer/kenkremer.com
The historic voyage of the largest and most sophisticated Martian rover ever built by humans seeks to determine if Mars ever offered conditions favorable for the genesis of microbial life.
Curiosity is packed to the gills with 10 state of the art science instruments that are seeking to detect the signs of life in the form of organic molecules – the carbon based building blocks of life as we know it.
The car sized robot is equipped with a drill and scoop at the end of its 7 ft long robotic arm to gather soil and powdered samples of rock interiors, then sieve and parcel out these samples into two distinct analytical laboratory instruments inside the rover.
