The Phobos-Grunt spacecraft is scheduled blastoff on November 9, 2011 from Baikonur Cosmodrome. It will reach Mars orbit in 2012 and eventually land on Phobos and return the first ever soil samples back to Earth in 2014. Credit Roscosmos
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Russia’s Space Agency, Roscosmos, has set November 9 as the launch date for the Phobos-Grunt mission to Mars and its tiny moon Phobos. Roscosmos has officially announced that the audacious mission to retrieve the first ever soil samples from the surface of Phobos will blastoff from the Baikonur Cosmodrome in Kazakhstan atop a Zenit-2SB rocket at 00:16 a.m. Moscow time.
Roscosmos said that engineers have finished loading all the propellants into the Phobos-Grunt main propulsion module (cruise stage), Phobos lander and Earth return module at Facility 31 at Baikonur.
Russian Phobos-Grunt spacecraft is set to launch to Mars on November 9, 2011.
L-shaped soil sample transfer tube extends from Earth return module ( top -yellow) and solar panel to bottom (left) of lander module. 2 landing legs, communications antenna, sampling arm, propulsion tanks and more are visible. Credit Roscosmos
Technicians also fueled the companion Yinghou-1 mini-satellite, provided by China, that will ride along inside a truss segment between the MDU propulsion module and the Phobos-Grunt lander.
The 12,000 kg Phobos-Grunt interplanetary spacecraft is being moved to an integration and test area at Facility 31 for integration with the departure segments of the Zenit rocket.
The next step is to enclose Phobos-Grunt inside the protective payload fairing and transport it to Facility 42 for mating atop the upper stage of the stacked Zenit-2SB booster rocket.
After about an 11 month journey, the spaceship will enter Mars orbit and spend several months searching for a suitable landing site on Phobos. The goal of the bold mission is to retrieve up to 200 grams of soil and rock from Phobos and return them to Earth in August 2014. The samples will help unlock the mysteries of the origin and evolution of Phobos, Mars and the Solar System.
Phobos-Grunt is equipped with a powerful 50 kg payload of some 20 international science instruments.
The 110 kg Yinghou-1, which translates as Firefly-1, is China’s first spaceship to voyage to Mars. It will be jettisoned by Phobos-Grunt into a separate orbit about Mars. The probe will photograph the Red planet with two cameras and study it with a magnetometer to explore Mars’ magnetic field and science instruments to explore its upper atmosphere.
Earth’s other mission to Mars in 2011, NASA’s Curiosity rover, is set to blast off for Mars on Nov. 25
Labeled Schematic of Phobos-Grunt and Yinghou-1 (YH-1) orbiter
In this image an Orion MultiPurpose Crew Vehicle jettison motor or JM, which is produced by Aerojet is test-fired. Photo Credit: Aerojet
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When it comes to space flight pedigrees, few companies have one that can compare to Aerojet’s. The California-based company has a resume on space operations that is as lengthy as it is impressive. Universe Today sat down with Julie Van Kleeck – the firm’s vice-president of space and launch systems business unit.
Van Kleeck spoke extensively about the company’s rich history, its legacy of accomplishments – as well as what it has planned for space missions of the future.
Universe Today:Hi Julie, thanks for taking the time to chat with us today.
Van Kleeck: “My pleasure!”
Universe Today:How long has Aerojet been in business and what exactly is it that your company produces?
Van Kleeck: “We’ve been in the space business – since there was a space program – so since at least the 50s. We’ve dealt with both launch systems as well as space maneuvering systems, those components that enable spacecraft to move while in space.”
Aerojet propulsion systems have helped many of NASA's deep-space probes explore the solar system. Image Credit: NASA.gov
Universe Today:What about in terms of human space flight, when did Aerojet get involved with that?
Van Kleeck: “We first started working on the manned side of the house back during the Gemini Program, from there we progressed to Apollo, then shuttle and we hope to be involved with SLS (Space Launch System) as well.”
Universe Today: I understand that your company also has an extensive history when it comes to unmanned missions as well, care to tell us a bit about that?
Van Kleeck: “We have been on every discovery mission that has ever been launched, we have touched every part of space that you can touch.”
It is Aerojet's solid rocket motors that provide that extra-added “punch” to the versions of the Atlas V launch vehicle that utilize them. Photo Credit: Alan Walters/awaltersphoto.com
Universe Today:Some aerospace companies only produce one product or service, why is Aerojet’s list of offerings so diversified?
Van Kleeck: “We’re quite different than our competitors in that we provide a very wide-range of products to our customers. We’ve provided the liquid engines that went on Titan and now we provide the solids that go on the Atlas V launch vehicle as well as the small chemical and electrical propulsion systems that are utilized on some satellites.”
An Aerojet AJ26 rocket engine is prepared for testing in this image. These engines, as well as a license to produce them, were purchased from Russia and were originally designated the NK-33. Picture Credit: Aerojet
Universe Today:Does this mean that Aerojet places more importance on one space flight system over others?
Van Kleeck: “We view each of the products that we produce as equally important. Having said that, the fact that Aerojet offers a diversity of products and understands each of them well – sets us apart from our competitors. Firms that only produce one type of product tend to work to sell just that one product, whereas Aerojet’s extensive catalog of services allows us to be more objective when offering those services to our customers.”
During a tour of the Vertical Integration Facility, Aerojet's Solid Rocket Motors or SRms -were on full display attached to the Atlas V rocket that is set to send the Mars Science Laboratory rover "Curiosity" to Mars. Photo Credit: Alan Walters/awaltersphoto.com
Universe Today:When you look back, what is one of the most interesting projects that Aerojet has been involved with?
Van Kleeck: “I think as I look back over the past decade, New Horizons comes to mind, it was the first Atlas to launch with five solids on it. I look at that mission in particular as a major accomplish for not just us – but the country as well.”
In this image an AJ26 liquid rocket engine is tested. These engines are utilized as part of Orbital Science's Taurus II program. Photo Credit: Aerojet
Universe Today:What does the future hold for Aerojet?
Van Kleeck: ”We’re working on the Orion crew capsule right now with both liquid propulsion for it as well as solid propulsion for the abort test motor. We’re very much looking forward to seeing Orion fly in the coming years. We are currently putting into place the basic infrastructure to support human space exploration. We are working with both commercial crewed as well as Robert Bigelow to provide propulsion systems that work with their individual system – because no one system fits everyone. We are pleased to be offer systems for a wide variety of space exploration efforts.”
Universe Today:Julie, thanks for taking the time to chat with us today!
Van Kleeck: “No problem at all – it was my pleasure!”
Aerojet’s products will be on full display Nov. 25 as, if everything goes as planned the Mars Science Laboratory (MSL) rover Curiosity is set to launch on that day. Four of the company’s solid rocket motors or SRMs will help power the Curiosity rover on its way to the red planet.
For a taste of what Aerojet’s SRMs provide – please view the NASA video below.
Artist's rendering of the distant dwarf planet Eris. New suggests that Eris is almost exactly the same diameter as Pluto. Eris is very reflective - possibly due to the frozen remains of its atmosphere. Image Credit: ESO/L. Calçada
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Back a couple of weeks ago, I wrote an article highlighting the debate between scientists on which dwarf planet is bigger, Pluto or Eris. During a planetary science conference earlier this month in France, word “leaked” out that Eris was still more massive, but likely smaller in diameter.
Today, the latest findings were published in Nature, and as such are now “official”. There’s also some additional information, so I’d like to revisit this topic and include some new details which may help answer the question:
Bruno Sicardy of the Paris Observatory and his team calculated the diameter of Eris in 2010. The technique they used took advantage of an occultation between Eris and a faint background star. Sicardy’s results provided a diameter of 2,326 kilometers for Eris, slightly less than his 2009 estimate of Pluto’s diameter at 2,338 kilometers.
Combining the diameter estimate with mass estimates yielded a density estimate for Eris which suggests, and is supported by its extra mass, that its composition is far more rocky than Pluto, with Eris being only 10-15% ice by mass.
In this week’s announcement by the European Southern Observatory, additional information was presented which sheds new light on cold, distant Eris.
Regarding the new density estimates, Emmanuel Jehin, one of Sicardy’s team members mentions, “This density means that Eris is probably a large rocky body covered in a relatively thin mantle of ice”.
Further supporting Jehin’s assertion, The surface of Eris was found to be extremely reflective, (96% of the light that falls on Eris is reflected, making it nearly as reflective as a backyard telescope mirror). Based on the current estimate, Eris is more reflective than freshly fallen snow on Earth. Based on spectral analysis of Eris, its surface reflectivity is most likely due to a surface of nitrogen-rich ice and frozen methane. Some estimates place the thickness of this layer at less than one millimeter.
Jehin also added, “This layer of ice could result from the dwarf planet’s nitrogen or methane atmosphere condensing as frost onto its surface as it moves away from the Sun in its elongated orbit and into an increasingly cold environment. The ice could then turn back to gas as Eris approaches its closest point to the Sun, at a distance of about 5.7 billion kilometers.”
Based on the new information on surface composition and surface reflectivity, Sicardy and his team were able to make temperature estimates for Eris. The team estimates daytime temperatures on Eris of -238 C, and that temperatures on the night side of Eris would be much lower.
Sicardy concluded with, “It is extraordinary how much we can find out about a small and distant object such as Eris by watching it pass in front of a faint star, using relatively small telescopes. Five years after the creation of the new class of dwarf planets, we are finally really getting to know one of its founding members.”
Curiosity Mars Science Laboratory (MSL)- all elements assembled into flight configuration in the Payload Hazardous Servicing Facility at NASA’s Kennedy Space Center in Florida. The top portion is the cruise stage attached to the aeroshell (containing the compact car-sized rover) with the heat shield on the bottom. Launch of MSL aboard a United Launch Alliance Atlas V rocket is scheduled for Nov. 25 from Space Launch Complex 41 on Cape Canaveral Air Force Station in Florida. Credit: NASA/Glenn Benson
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Take a good last, long look at the magnificent robot that is Curiosity, because she’s been all buttoned up for her long Martian voyage in search of the ingredients of life. After years of exhaustive work, the most technologically advanced surface robotic rover ever to be sent beyond Earth has been assembled into the flight configuration, a NASA spokesperson informed Universe Today.
The next time Curiosity opens her eyes she will have touched down at the foot of a layered mountain inside the planet’s Gale crater.
Curiosity Mars rover folded for flight and mated to the cruise stage. The cruise stage provides solar power, thrusters for navigation, and heat exchangers to the rover during its flight from Earth to Mars. Credit: NASA/Glenn Benson
Curiosity – NASA’s next Mars rover – is formally known as the Mars Science Laboratory (or MSL) and has entered the final stages of preflight processing.
After extensive quality assurance testing, Curiosity has been encapsulated for the final time inside the aeroshell that will be her home during the 10 month long interplanetary cruise to Mars. Furthermore, she’s been attached to the cruise stage that will guide her along the path from the home planet to the red planet.
Curiosity Mars Science Laboratory (MSL) assembled into flight configuration in the Payload Hazardous Servicing Facility at NASA’s Kennedy Space Center in Florida. The rover Curiosity has 10 science instruments designed to search for evidence on whether Mars has had environments favorable to microbial life, including chemical ingredients for life. Credit: NASA/Glenn Benson
The work to combine all the components into an integrated assembly was carried out inside the clean room facilities of the Payload Hazardous Servicing Facility at NASA’s Kennedy Space Center (KSC) in Florida.
The aeroshell is comprised of the heat shield and back shell.
The job of the aeroshell is to protect Curiosity from the intense heat of several thousand degrees F(C) generated by friction as the delicate assemblage smashes into the Martian atmosphere at about 13,200 MPH (5900 m/s) and plummets some 81 miles during the terrifying seven minute long entry, descent and landing (EDL) on the surface.
The massive 2000 lb (900 kg) rover is folded up and mated to the back shell powered descent vehicle, known as the PDV or Sky Crane. The spacecraft is designed to steer itself through a series of S-curve maneuvers to slow the spacecraft’s descent through the Martian atmosphere.
In the final moments, the rocket powered Sky crane will lower the robot on tethers and then safely set Curiosity down onto the ground at a precise location inside the chosen landing site astride a layered mountain in Gale Crater believed to contain phyllosilicate clays and hydrated sulfate minerals that formed in liquid water.
The robot is the size of a compact car and measures three meters in length, roughly twice the size of the MER rovers; Spirit and Opportunity. It is equipped with 10 science instruments for a minimum two year expedition across Gale crater.
NASA's Curiosity Mars Science Laboratory Rover
Inside the Clean room at the Payload Hazardous Servicing Facility at the Kennedy Space Center.
The science payload weighs ten times more than any prior Mars rover mission. Curiosity will zap rocks with a laser and deftly maneuver her outstretched robotic arm to retrieve and analyze dozens of Martian soil samples. Credit: Ken Kremer
Curiosity will search for the ingredients of life including water and organic molecules and environmental conditions that could have been hospitable to sustaining Martian microbial life forms if they ever existed in the past or survived to the present through dramatic alterations in Mars climatic and geologic history.
Liftoff of the $2.5 Billion Curiosity rover is slated for Nov. 25 from Cape Canaveral Air Force Station in Florida on a United Launch Alliance Atlas V booster rocket. The launch window to Mars extends until Dec. 18.
This coming week, Curiosity will be encapsulated into the clamshell like payload fairing and the MSL logo will then be applied to the fairing, KSC spokesman George Diller told Universe Today. It will then be hoisted onto the payload transporter and carefully conveyed to Space Launch Complex 41 on Nov. 2, for mating atop the Atlas V rocket.
Mars Science Laboratory Aeroshell with Curiosity enclosed inside. Credit: NASA
Russia’s Phobos-Grunt sample return spacecraft is uncrated after arriving at the Baikonur Cosmodrome on Oct. 17, 2011. Launch to Mars is scheduled for sometime in November 2011. Folded solar panels and Phobos sample return vehicle at left. Phobos Lander and Yinghou-1 Orbiter at center, right. Credit: Roskosmos.
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Barely in the nick of time, Russia’s groundbreaking Phobos-Grunt interplanetary spacecraft to Mars finally arrived on Monday (Oct. 17) at the Baikonur Cosmodrome launch site in Kazakhstan – and today (Oct. 18) an eye-popping collection of great images (see below) was at last published by Roskosmos, the Russian Federal Space Agency.
This first-of-its-kind spaceship is due to blast off quite soon – sometime in the first half of November – although Roskosmos has yet to announce an official launch date and time is running out. The deadline to Mars is Nov. 25.
Top view of Phobos-Grunt, sample return vehicle. Credit: Roskosmos.
The explicit close-up photos show both the Phobos-Grunt orbiter/lander vehicle and her companion Yinghou-1 Mars orbiter, built by China, being uncrated from a huge shipping container, uprighted and then showcased from many revealing angles from top to bottom, tilted from side to side and looking inside her hardware stack.
The photos illustrate the solar panels, landing legs, J-shaped soil sampling tube, Earth return vehicle and descent capsule, star trackers, communications antennae, maneuvering thrusters and more.
Top view of Phobos-Grunt, sample return vehicle. Credit: Roskosmos.
The Yinghou-1 mini-satellite is clearly visible tucked inside a truss situated between the Phobos-Grunt landing ship and the MDU propulsion stage.
Phobos-Grunt was just air shipped from Moscow to Baikonur inside an Antonov An-124-100 “Ruslan” cargo plane operated by “Polyot” airline.
The cargo canister was offloaded and transported by truck to Facility 31. The spacecraft was then placed on a test stand to begin an intense period of final prelaunch payload processing activites to ready the probe for launch.
The Zenit-2SB booster rocket also recently arrived at Baikonur for ongoing prelaunch processing at nearby Building 42.
Chinese Yinghou-1 mini-satellite tucked truss at right, situated below the Phobos-Grunt lander at left. Credit: Roskosmos.
Russia’s engineers and technicians will have to work diligently in the few weeks remaining in order to complete all preflight activities to achieve a liftoff to the Red Planet before the unforgiving and narrow launch window closes for another 26 months.
Phobos-Grunt Earth return spacecraft. Close-up view of solar panels, Earth descent capsule and soil sample transfer tube. Credit: Roskosmos.Phobos-Grunt sample collecting and sample return vehicle. Credit: Roskosmos.
Tilted view of Phobos-Grunt attached to test stand for final prelaunch processing. Credit: Roskosmos.
Earth is actually lofting two exciting science missions to Mars this November. NASA’s Curiosity Mars Science Laboratory rover is due to blastoff on Nov. 25 and her launch window extends until Dec. 18. Both spaceships missed their initially targeted launch windows in 2009 due to the need to fix unresolved technical issues.
Phobos-Grunt is a daring sample return mission whose goal is to retrieve up to 200 grams of soil and rock from the tiny Martian moon Phobos, that will help elucidate the origin and evolution of Phobos, Mars and the Solar System.
Tilted view of Phobos-Grunt attached to test stand for final prelaunch processing. Credit: Roskosmos.
Side view of Phobos-Grunt and Yinghou-1 orbiter (bottom) attached to test stand for final prelaunch processing. Credit: Roskosmos. Labeled Schematic of Phobos-Grunt and Yinghou-1 (YH-1) orbiter
The cracked ice surface of Europa. Credit: NASA/JPL
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Until fairly recently, the search for life elsewhere in the solar system has focused primarily on Mars, as it is the most Earth-like of all the other planets in the solar system. The possibility of finding any kind of life farther out in the outer solar system was considered very unlikely at best; too cold, too little sunlight, no solid surfaces on the gas giants and no atmospheres to speak of on any of the moons apart from Titan.
But now, some of the places that were previously considered the least likely to hold life have turned out to be perhaps some of the most likely to provide habitable environments. Moons that were thought be cold and frozen for eons are now known to be geologically active, in surprising ways. One of them is the most volcanically active place known in the solar system. At least two others appear to have oceans of liquid water beneath their surfaces. That’s right, oceans. And geysers. On the surface, they are ice worlds, but below, they are water worlds. Then there’s the one with rain, rivers, lakes and seas, but made of liquid methane instead of water. Billions of kilometres farther out from the Sun than the Earth. Who would have thought? Let’s look at those last three in a bit more detail…
Ever since the film 2001: A Space Odyssey first came out, Europa has been the subject of fascination. A small, icy moon orbiting Jupiter, its depiction in that movie, as an inhabited world beneath its ice crust was like a sort of foreshadowing, before the Voyager and Galileo spacecraft gave us our first real close-up looks of this intriguing place. Its surface shell of ice is covered with long cracks and fissures, giving it an appearance much like ice floes at the poles on Earth. More surprising though, was the discovery that, also like on Earth, this ice cover most likely is floating on top of a deep layer of liquid water below. In Europa’s case though, the water layer appears to cover the entire moon, a global subsurface ocean. How is this possible? If there is liquid water, there must be heat (or high concentrations of salts or ammonia), and if you have water and heat, could there be something living in those waters? Gravitational tugging from Jupiter indeed appears to provide enough heat to keep the water liquid instead of frozen. The environment is now thought to be similar to ocean bottoms on Earth. No sunlight, but if there are volcanic vents generating heat and minerals, as on Earth, such a spot could be ideal for at least simple forms of life. On Earth, places like these deep in the oceans are brimming with organisms which don’t require sunlight to survive.
Water vapour geysers on Enceladus. Credit: NASA/JPL
Then there’s Enceladus. Another very small icy moon, orbiting Saturn. Geological activity was considered very unlikely on such a tiny world, only a few hundred kilometres in diameter. But then Cassini saw the geysers, plumes of material erupting from the south polar region through large, warmer cracks nicknamed “tiger stripes.” Cassini has now flown directly through the geysers, analyzing their composition, which is mostly water vapour, ice particles, salts and organics. The latest analysis based on the Cassini data indicates that they almost certainly originate from a sea or ocean of liquid water below the surface. Warm, salty water loaded with organics; could Enceladus be another possible niche for extraterrestrial life? As with Europa, only further missions will be able to answer these questions, but the possibilities are exciting.
Radar image of one of many methane lakes on Titan. Credit: NASA/JPL
Titan is even more fascinating in some ways, the largest moon of Saturn. It is perpetually shrouded in a thick smoggy atmosphere of nitrogen and methane, so the surface has never been visible until now, when Cassini, and its small lander probe Huygens, first looked below the smog and clouds. Titan is like an eerily alien version of Earth, with rain, rivers, lakes and seas, but being far too cold for liquid water (not much heat here), its “water cycle” is composed of liquid methane/ethane. Appearance-wise, the surface and geology look amazingly Earth-like, but the conditions are uniquely Titan. For that reason, it has long been considered that the chances of any kind of life existing here are remote at best. In the last few years however, some scientists are starting to consider the possibility of life forming in just such environments, using liquids other than water, even in such cold conditions. Could life occur in a liquid methane lake or sea? How would it differ from water-based life? Last year, a discovery was made which might be interpreted as evidence of methane-based life on Titan – a seeming disappearance of hydrogen from the atmosphere near the surface and a lack of acetylene on the surface. Previous theoretical studies had suggested that those two things, if ever found, could be evidence for methane-based lifeforms consuming the hydrogen and acetylene. All of this is still highly speculative, and while a chemical explanation is probably more likely according to the scientists involved, a biological one cannot be ruled out yet. Future proposed missions for Titan include a floating probe to land in one of the lakes and a balloon to soar over the landscape, pursuing such mysteries as never before. How cool is that?
Oh, and the moon that is the most volcanically active place in the solar system? Io, although with the only known forms of liquid there being extremely hot lavas on that sulfuric hothouse, the chances of life are still thought to be unbelievably slim. But that’s ok when you start to find out that worlds with oceans and lakes, etc. may be much more common than previously imagined…
Southern Hemisphere of Vesta; Rheasilvia and Older Basin. Colorized shaded-relief map showing identification of older 375-kilometer-wide impact basin beneath and overlapping with the more recent Rheasilvia impact structure at asteroid Vesta’s South Pole. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
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Scientists leading NASA’sDawn mission have discovered a 2nd giant impact basin at the south pole of the giant asteroid Vesta, which has been unveiled as a surprisingly “dichotomous” and alien world. Furthermore, the cosmic collisions that produced these two basins shuddered through the interior and created vast Vestan troughs, a Dawn scientist told Universe Today.
The newly discovered impact basin, nicknamed ‘Older Basin’, is actually significantly older in age compared to the initially discovered South Pole basin feature named ‘Rheasilvia’ – perhaps by more than a billion years. And that is just one of the many unexplained mysteries yet to be reconciled by the team as they begin to sift through the millions of bits of new data streaming back daily to Earth.
Scientists speculate that ‘Older Basin’ is on the order of 3.8 Billion years old, whereas ‘Rheasilvia’ might be as young as about 2.5 Billion years, but those are just tentative estimates at this time and subject to change. Measurements so far indicate Rheasilvia is composed of basaltic material.
Shaded-relief topographic map of Vesta southern hemisphere showing two large impact basins - Rheasilvia and Older Basin.
Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
“We found many surprising things at Vesta, which is quite unique and the results have exceeded our expectations”, said Dr. Carol Raymond, Dawn deputy principal investigator, of NASA’s Jet Propulsion Laboratory, Pasadena, Calif.
Researchers presented the latest findings from Dawn’s initial science mapping orbit at a news briefing at the annual meeting of the Geological Society of America in Minneapolis, Minn., on Oct. 13.
The team considers Vesta to be the smallest terrestrial planet.
Since achieving orbit in July, Dawn’s Framing Cameras (FC) have imaged most of Vesta at about 250 meter resolution and the Visible and Infrared mapping spectrometer(VIR) at about 700 meter resolution. The measurements were collected at the survey orbit altitude of 2700 km. Before Dawn, Vesta was just a fuzzy blob in humankind’s most powerful telescopes.
Vesta from Hubble (top) as a fuzzy blob and from Dawn in orbit (bottom) in crystal clear high resolution.
Credit: NASA/JPL-Caltech/ UCLA/MPS/DLR/IDA
“There is a global dichotomy on Vesta and a fundamental difference between the northern and southern hemispheres”, said Raymond. “The northern hemisphere is older and heavily cratered in contrast to the brighter southern hemisphere where the texture is more smooth and there are lots of sets of grooves. There is a massive mountain at the South Pole. One of the more surprising aspects is the set of deep equatorial troughs.”
“There is also a tremendous and surprising diversity of surface color and morphology. The south is consistent with basaltic lithology and the north with impacts. We are trying to make sense of the data and will integrate that with the high resolution observations we are now collecting.”
Indeed Vesta’s completely unique and striking dichotomy can be directly traced back to the basins which were formed by ancient cataclysmic impacts resulting in shockwaves that fundamentally altered the surface and caused the formation of the long troughs that ring Vesta at numerous latitudes.
“The troughs extend across 240 degrees of longitude,” said Debra Buczkowski, Dawn participating scientist, of the Applied Physics Laboratory at Johns Hopkins University, Laurel, Md. “Their formation can be tied back to the two basins at the South Pole.”
Asteroid Vesta and Equatorial Grooves
This full view of the giant asteroid Vesta was taken by NASA’s Dawn spacecraft, as part of a rotation characterization sequence on July 24, 2011, at a distance of 3,200 miles (5,200 kilometers). A rotation characterization sequence helps the scientists and engineers by giving an initial overview of the character of the surface as Vesta rotated underneath the spacecraft. This view of Vesta shows impact craters of various sizes and grooves parallel to the equator. The resolution of this image is about 500 meters per pixel. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
In an exclusive follow up interview with Universe Today, Raymond said “We believe that the troughs formed as a direct result of the impacts,” said “The two sets of troughs are associated with the two large basins [Rheasilvia and Older Basin].”
“The key piece of evidence presented was that the set of troughs in the northern hemisphere, that look older (more degraded) are circumferential to the older impact basin,” Raymond told me.
“The equatorial set are circumferential to Rheasilvia. That Rheasilvia’s age appears in places to be much younger is at odds with the age of the equatorial troughs. An explanation for that could be resurfacing by younger mass wasting features (landslides, slumps). We will be working on clarifying all these relationships in the coming months with the higher resolution HAMO (High Altitude Mapping Orbit) data.”
Dawn has gradually spiraled down closer to Vesta using her exotic ion thrusters and began the HAMO mapping campaign on Sept. 29.
Surface features are dated by crater counting methodology.
“Preliminary crater counting age dates for the equatorial trough region yields a very old age (3.8 Billion years). So there is a discrepancy between the apparent younger age for the Rheasilvia basin and the old age for the troughs. These could be reconciled if Rheasilvia is also 3.8 Billion years old but the surface has been modified by slumping or other processes,” Raymond elaborated.
Time will tell as further data is analyzed.
Dawn launch on September 27, 2007 by a Delta II Heavy rocket from Cape Canaveral Air Force Station, Florida. Credit: Ken Kremer
“Vesta is full of surprises, no more so than at the South Pole,” said Paul Schenk at the GSA briefing. Schenk is a Dawn participating scientist of the Lunar and Planetary Institute, Houston, Texas.
The ‘Rheasilvia’ basin was initially discovered in images of Vesta taken a decade ago by the Hubble Space Telescope which revealed it as a gaping hole in the southern hemisphere. But it wasn’t until Dawn entered orbit on July 16, 2011 after a nearly four year interplanetary journey that Earthlings got their first close up look at the mysterious polar feature and can now scrutinize it in detail to elucidate its true nature.
“The South Pole [Rheasilvia] basin is a roughly circular, impact structure and a deep depression dominated by a large central mound,” said Schenk. “It shows sharp scarps, smooth areas, landslide deposits, debris flows. It’s about 475 km in diameter and one of the deepest (ca. 20 -25 km) impact craters in the solar system.”
The central peak is an enormous mountain, about 22 km high and 180 km across- one of the biggest in the solar system. “It’s comparable in some ways to Olympus Mons on Mars,” Schenk stated.
“We were quite surprised to see a second basin in the mapping data outside of Rheasilvia. This was unexpected. It’s called ‘Older Basin’ for now.”
‘Older Basin’ is about 375 km in diameter. They overlap at the place where Rheasilvia has a missing rim.
“These basins are interesting because we believe Vesta is the source of a large number of meteorites, the HED meteorites that have a spread of ages,” Schenk explained.
Images showing key components of Rheasilvia impact basin on Vesta in high resolution ,referred to Shaded-relief topographic map. Credit: NASA/JPL-Caltech/ UCLA/MPS/DLR/IDA
Multiple large impacts over time may explain the source of the HED (Howardite, Eucrite and Diogenite) meteorites.
“We did expect large impacts on Vesta, likely associated with the late heavy bombardment recognized in the lunar impact record,” Raymond told Universe Today. “The surprising element is that the two apparently largest impacts – keeping in mind that other larger impact basins may be lurking under the regolith – are overlapping.”
Dawn’s VIR spectrometer has detected pyroxene bands covering Vesta’s surface, which is indicative of typical basaltic material, said Federico Tosi, a VIR team member of the Italian Space Agency, Rome. “Vesta has diverse rock types on its surface.”
“VIR measured surface temperatures from 220K to 270 K at the 5 micron wavelength. The illuminated areas are warmer.”
So far there is no clear indication of olivine which would be a marker for seeing Vesta’s mantle, Tossi elaborated.
The VIR spectrometer combines images, spectral information and temperature that will allow researchers to evaluate the nature, composition and evolutionary forces that shaped Vesta’s surface.
The team is absolutely thrilled to see a complicated geologic record that’s been preserved for study with lots of apparent surface layering and surprisingly strong and complex structural features with a large range of color and brightness.
Stay tuned for a year of Vestan delights !
Asteroid Vesta from Dawn
South Pole Rheasilvia basin is at lower right. NASA's Dawn spacecraft obtained this image of the giant asteroid Vesta with its framing camera on July 24, 2011 from a distance of about 3,200 miles (5,200 kilometers). Dawn entered orbit around Vesta on July 16, and will spend a year orbiting the body.
Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
<>. Mission Poster for the Russian Phobos-Grunt soil sample return spacecraft set to launch to Mars and its moon Phobos in November 2011. Phobos-Grunt consistes Credit: Roskosmos - Russian Federal Space Agency
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Russia is marking the upcoming blastoff of their dauntingly complex Phobos-Grunt sample return mission to the Martian moon Phobos with the release of a quite cool looking mission poster – see above. Phobos-Grunt translates as Phobos-Soil and is due to liftoff on or about November 7, 2011 from the Baikonur Cosmodrome atop a Zenit rocket.
The holy grail of Mars exploration has long been a sample return mission. But with severe cutbacks to NASA’s budget that goal is realistically more than a decade away. That’s why Phobos- Grunt is so exciting from a scientific standpoint.
Phobos-Grunt Orbiter/Lander
Russia's Phobos-Grunt is designed to land on Mars' moon Phobos, collect soil samples and return them to Earth for study. The lander will also carry scientific instrumetns to study Phobos and its environment. It will travel to Mars together with Yinghuo-1, China's first mission to the Red Planet. Credit: NPO Lavochkin
Phobos-Grunt Robotic sampling arm. Credit: Roskosmos
If successful, this audacious probe will retrieve about 200 grams of soil from the diminutive moon Phobos and accomplish the round trip in three years time by August 2014. Scientists speculate that martian dust may coat portions of Phobos and could possibly be mixed in with any returned samples.
Included here are more photos and graphics of the Phobos-Grunt spacecraft which is equipped with two robotic arms and a sampling device to transfer regolith and rocks to the Earth return vehicle and an on board array of some 15 science instruments, including lasers, spectrometers, cameras and a microscope. Readers please feel free to help with Russian translations.
Phobos-Grunt Model
This is a full-scale mockup of Russia's Phobos-Grunt. The spacecraft will collect samples of soil on Mar's moon Phobos and to bring the samples back to Earth for detailed study. Credit: CNES
Phobos-Grunt is the first of Earth’s two missions launching to the Red Planet in 2011. NASA’s Curiosity Mars Science Laboratory is due to lift off on Nov. 25, 2011 from Cape Canaveral, Florida.
Hubble image of Pluto and some of its moons, Charon, Nix and Hydra. Image Credit: NASA, ESA, H. Weaver (JHU/APL), A. Stern (SwRI), and the HST Pluto Companion Search Team
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The controversy between Pluto and Eris regarding their status as “largest dwarf planet” continues. During a joint meeting of the American Astronomical Society Division for Planetary Sciences and the European Planetary Science Congress last week in Nantes, France, new data was presented that may help settle the debate. The new findings regarding this size of Eris may be a surprise to some, and to others a confirmation of what was believed to be true.
How were astronomers able to make the new measurements of Eris, and what implications will these new measurements have on the Pluto / Eris debate?
Using a celestial alignment known as an occultation, Bruno Sicardy of the Paris Observatory (University of Pierre and Marie Curie, France) and his team were able calculate the diameter of Eris in 2010. The occultation was caused by Eris moving past a background star, which blocked the star’s light and cast a small shadow on Earth. When Sicardy and his team compared the shadow’s size at two different sites in Chile, the calculations provided a diameter of 2,326 kilometers for Eris. A previous study by Sicardy in 2009 placed Pluto’s diameter to be at least 2,338 kilometers.
However, the first estimates of Eris’ size that were made shortly after its discovery put the diameter at 3,000 km, plus or minus 400 km. But a later estimate from observations with the Hubble Space Telescope said Eris might be 2,400 km in diameter, plus or minus 100 km.
If Sicardy’s data calculations hold true, this places Pluto and Eris at nearly the exact same diameter. What has continued to not be up for debate, however, is that Eris is far more massive than Pluto. Given a nearly identical diameter for Eris and Pluto, Eris’s extra mass makes it the denser of the two dwarf planets. According to Sicardy and his team the increased density of Eris, “indicates that Eris is mainly composed of rocky material, with a relatively thin ice mantle.” Since Pluto’s density indicates it comprised of about equal parts ice and rock, Eris’s extra mass would appear to validate Sicardy’s assertion.
Eris and its moon, Dysnomia. Credit: NASA, ESA, and M. Brown (California Institute of Technology)
The Co-discoverer of Eris, and noted “Plutokiller” Mike Brown (Caltech) offers an interesting thought regarding the Pluto / Eris Debate:
“Scientifically, knowing which one is bigger will teach us…. absolutely nothing. The fact that they are nearly identical in size is scientifically interesting; which one is a few kilometers bigger than the other matters not one bit.” Brown also added, “But, still, I will admit to having a bit of an emotional attachment to Eris, so, deep down inside, I want to believe it will turn out to be a little bigger.
Russian Phobos-Grunt spacecraft set to Launch in November 2011.The flight version of the Phobos-Grunt spacecraft minus its main solar panels is being lowered into a vacuum chamber at NITs RKP test facility in Peresvet, north of Moscow, for thermal, vacuum and electric tests around beginning of June 2011. Credit: NPO Lavochkin
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In just over 3 weeks’ time, Russia plans to launch a bold mission to Mars whose objective, if successful , is to land on the Martian Moon Phobos and return a cargo of precious soil samples back to Earth about three years later.
The purpose is to determine the origin and evolution of Phobos and how that relates to Mars and the evolution of the solar system.
Liftoff of the Phobos-Grunt space probe will end a nearly two decade long hiatus in Russia’s exploration of the Red Planet following the failed Mars 96 mission and is currently scheduled to head to space just weeks prior to this year’s other Mars mission – namely NASA’s next Mars rover, the Curiosity Mars Science Laboratory (MSL).
Blastoff of Phobos-Grunt may come as early as around Nov. 5 to Nov. 8 atop a Russian Zenit 3-F rocket from the Baikonur Cosmodrome in Kazakhstan. The launch window extends until about Nov. 25. Elements of the spacecraft are undergoing final prelaunch testing at Baikonur.
Flight version of the Phobos-Grunt spacecraft during assembly in preparation for critical testing in thermal and vacuum chamber at NITs RKP facility closely imitating harsh conditions of the real space flight. Credit: NPO Lovochkin
Baikonur is the same location from which Russian manned Soyuz rockets lift off for the International Space Station. Just like NASA’s Curiosity Mars rover, the mission was originally intended for a 2009 launch but was prudently delayed to fix a number of technical problems.
“November will see the launch of the Phobos-Grunt interplanetary automatic research station aimed at delivering samples of the Martian natural satellite’s soil to Earth’” said Vladimir Popovkin, head of the Russian Federal Space Agency, speaking recently at a session of the State Duma according to the Voice of Russia, a Russian government news agency.
Phobos-Grunt spacecraft
The spacecraft will reach the vicinity of Mars after an 11 month interplanetary cruise around October 2012. Following several months of orbital science investigations of Mars and its two moons and searching for a safe landing site, Phobos-Grunt will attempt history’s first ever touchdown on Phobos. It will conduct a comprehensive analysis of the surface of the tiny moon and collect up to 200 grams of soil and rocks with a robotic arm and drill.
Russian Phobos-Grunt spacecraft prepares for testing inside the vacuum chamber. Credit: NPO Lavochkin
After about a year of surface operations, the loaded return vehicle will blast off from Phobos and arrive back at Earth around August 2014. These would be the first macroscopic samples returned from another body in the solar system since Russia’s Luna 24 in 1976.
“The way back will take between nine and 11 months, after which the return capsule will enter Earth’s atmosphere at a speed of 12 kilometers per second. The capsule has neither parachute nor radio communication and will break its speed thanks to its conical shape,” said chief spacecraft constructor Maksim Martynov according to a report from the Russia Today news agency. He added that there are two soil collection manipulators on the lander because of uncertainties in the characteristics of Phobos soil.
Phobos-Grunt was built by NPO Lavochkin and consists of a cruise stage, orbiter/lander, ascent vehicle, and Earth return vehicle.
The spacecraft weighs nearly 12,000 kg and is equipped with a sophisticated 50 kg international science payload, in particular from France and CNES, the French Space Agency.
Also tucked aboard is the Yinghou-1 microsatellite supplied by China. The 110 kg Yinghou-1 is China’s first probe to launch to Mars and will study the Red Planet’s magnetic and gravity fields and surface environment from orbit for about 1 year.
“It will be the first time such research [at Mars] will be done by two spacecraft simultaneously. The research will help understand how the erosion of Mars’ atmosphere happens,” said Professor Lev Zelyony from the Space Research Institute of the Russian Academy of Science, according to Russia Today.
Phobos-Grunt mission scenario. Credit: CNESPhobos seen by Mars Express. Credit: ESA
