Jupiter, the largest and most massive planet in our solar system, may be its own worst enemy. It turns out that its central core may in fact be self-destructing, gradually liquifying and dissolving over time. This implies it was previously larger than it is now, and may dissolve altogether at some point in the future. Will Jupiter eventually destroy itself completely? No, probably not, but it may lose its heart…
The core is composed of iron, rock and ice and weighs about ten times as much as Earth. That’s still small though, compared to the overall mass of Jupiter itself, which weighs as much as 318 Earths! The core is buried deep within the thick atmosphere of hydrogen and helium. Conditions there are brutal, with a temperature of about 16,000 kelvin – hotter than the surface of the Sun – and a pressure about 40 million times greater than the atmospheric pressure on Earth. The core is surrounded by a fluid of metallic hydrogen which results from the intense pressure deep down in the atmosphere. The bulk of Jupiter though is the atmosphere itself, hence why Jupiter (and Saturn, Uranus and Neptune) are called gas giants.
One of the primary ingredients in the rock of the core is magnesium oxide (MgO). Planetary scientists wanted to see what would happen when it is subjected to the conditions found at the core; they found that it had a high solubility and started to dissolve. So if it is in a state of dissolution, then it was probably larger in the past than it is now and scientists would like to understand the process. According to David Stevenson of the California Institute of Technology, “If we can do that, then we can make a very useful statement about what Jupiter was like at genesis. Did it have a substantial core at that time? If so, was it 10 Earth masses, 15, 5?”
The findings also mean that some exoplanets which are even larger and more massive than Jupiter, and thus likely even hotter at their cores, may no longer have any cores left at all. They would be indeed be gas giants in the most literal sense.
The conditions inside Jupiter’s core can’t be duplicated in labs yet, but the spacecraft Juno should provide much more data when it arrives at and starts orbiting Jupiter in 2016.
NASA's Mars Science Laboratory Curiosity rover will investigate Mars' past or present ability to sustain microbial life. Curiosity is cruising to Mars and has already investigating the lethality of the space radiation environment to humans. Credit: NASA/JPL-Caltech
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Barely two weeks into the 8 month journey to the Red Planet, NASA’sCuriosity Mars Science Lab (MSL) rover was commanded to already begin collecting the first science of the mission by measuring the ever present radiation environment in space.
Engineers powered up the MSL Radiation Assessment Detector (RAD) that monitors high-energy atomic and subatomic particles from the sun, distant supernovas and other sources.
RAD is the only one of the car-sized Curiosity’s 10 science instrument that will operate both in space as well as on the Martian surface. It will provide key data that will enable a realistic assessment of the levels of lethal radiation that would confront any potential life forms on Mars as well as Astronauts voyaging between our solar systems planets.
“RAD is the first instrument on Curiosity to be turned on. It will operate throughout the long journey to Mars,” said Don Hassler, RAD’s principal investigator from the Southwest Research Institute in Boulder, Colo.
These initial radiation measurements are focused on illuminating possible health effects facing future human crews residing inside spaceships.
Video Caption: The Radiation Assessment Detector is the first instrument on Curiosity to begin science operations. It was powered up and began collecting data on Dec. 6, 2011. Credit: NASA
“We want to characterize the radiation environment inside the spacecraft because it’s different from the radiation environment measured in interplanetary space,” says Hassler.
RAD is located on the rover which is currently encapsulated within the protective aeroshell. Therefore the instrument is positioned inside the spacecraft, simulating what it would be like for an astronaut with some shielding from the external radiation, measuring energetic particles.
“The radiation hitting the spacecraft is modified by the spacecraft, it gets changed and produces secondary particles. Sometimes those secondary particles can be more damaging than the primary radiation itself.”
“What’s new is that RAD will measure the radiation inside the spacecraft, which will be very similar to the environment that a future astronaut might see on a future mission to Mars.”
Curiosity Mars Science Laboratory (MSL) Spacecraft During Cruise with Navigation Stars. Artist's concept of Curiosity during its cruise phase between launch on Nov. 26, 2011 and final approach to Mars in August 2012. Credit: NASA/JPL-Caltech
Curiosity’s purpose is to search for the ingredients of life and assess whether the rovers landing site at Gale Crater could be or has been favorable for microbial life.
The Martian surface is constantly bombarded by deadly radiation from space. Radiation can destroy the very organic molecules which Curiosity seeks.
“After Curiosity lands, we’ll be taking radiation measurements on the surface of another planet for the first time,” notes Hassler.
RAD was built by a collaboration of the Southwest Research Institute, together with Christian Albrechts University in Kiel, Germany with funding from NASA’s Human Exploration Directorate and Germany’s national aerospace research center, Deutsches Zentrum für Luft- und Raumfahrt.
“What Curiosity might find could be a game-changer about the origin and evolution of life on Earth and elsewhere in the universe,” said Doug McCuistion, director of the Mars Exploration Program at NASA Headquarters in Washington. “One thing is certain: The rover’s discoveries will provide critical data that will impact human and robotic planning and research for decades.”
Curiosity was launched from Florida on Nov. 26. After sailing on a 254 day and 352-million-mile (567-million-kilometer) interplanetary flight from the Earth to Mars, Curiosity will smash into the atmosphere at 13,000 MPH on August 6, 2012 and pioneer a nail biting and first-of-its-kind precision rocket powered descent system to touchdown inside layered terrain at Gale Crater astride a 3 mile (5 km) high mountain that may have preserved evidence of ancient or extant Martian life.
Miraculously, NASA’s Opportunity Mars rover and onboard instruments and cameras have managed to survive nearly 8 years of brutally harsh Martian radiation and arctic winters. Curiosity MSL science instruments are state-of-the-art tools for acquiring information about the geology, atmosphere, environmental conditions, and potential biosignatures on Mars. Credit: NASA
Dr. Alan Stern, Associate Vice President, Space Science and Engineering Division, Southwest Research Institute. Photo Credit: Southwest Research Institute
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We’re testing a new “Ask” article format here at Universe Today and we know you’ve got a question you’d like to ask Alan Stern!
Here’s how it works: Readers can submit questions they would like Universe Today to ask the guest responder. Simply post your question in the comments section of this article. We’ll take the top five (or so) questions, as ranked by “likes” on the discussion posts. If you see a question you think is good, click the “like” button to give it a vote.
Keep in mind that final question acceptance is based on the discretion of Universe Today and in some cases, the responder and/or their employer.
Our inaugural launch (pun intended) will feature Dr. Alan Stern, principal investigator for NASA’s “New Horizons” mission to Pluto.
Stern is a planetary scientist and an author who has published more than 175 technical papers and 40 popular articles. His research has focused on studies of our solar system’s Kuiper belt and Oort cloud, comets, satellites of the outer planets, Pluto and the search for evidence of solar systems around other stars. He has worked on spacecraft rendezvous theory, terrestrial polar mesospheric clouds, galactic astrophysics and studies of tenuous satellite atmospheres, including the atmosphere of the Moon.
Stern has a long association with NASA, serving the agency’s Associate Administrator for the Science Mission Directorate from 2007-2008; he was on the NASA Advisory Council and was the principal investigator on a number of planetary and lunar missions, including his current stint with the New Horizons Pluto-Kuiper Belt mission. He was the principal investigator of the Southwest Ultraviolet Imaging System, which flew on two space shuttle missions, STS-85 in 1997 and STS-93 in 1999.
He has been a guest observer on numerous NASA satellite observatories, including the International Ultraviolet Explorer, the Hubble Space Telescope, the International Infrared Observer and the Extreme Ultraviolet Observer.
Stern holds bachelor’s degrees in physics and astronomy and master’s degrees in aerospace engineering and planetary atmospheres from the University of Texas, Austin. In 1989, Stern earned a doctorate in astrophysics and planetary science from the University of Colorado at Boulder.
Aside from being the Principal Investigator for NASA’s “New Horizons” mission to Pluto, Currently Stern is the Associate Vice President of R&D – Space Science and Engineering Division at the Southwest Research Institute and recently was appointed director of the Florida Space Institute at Kennedy Space Center.
For those of you who are fans of Pluto, Dr. Stern went on the record against the IAU’s decision in 2006, stating “It’s an awful definition; it’s sloppy science and it would never pass peer review..”
Before submitting your question, take a minute and read a bit more about Dr. Stern at: Dr. Alan Stern
We’ll take questions until 4:00PM (MST) Tuesday December 20th and provide a follow up article with Dr. Stern’s responses to your questions.
All these worlds are yours except Europa Attempt no landing there Use them together use them in peace
Despite that famous cryptic warning in the film 2010: The Year We Make Contact, NASA is planning for a possible attempted landing on Jupiter’s moon Europa. This is a mission that many people have been hoping for, since Europa is believed to have a liquid water ocean beneath the icy surface (as well as lakes within the surface crust itself), making it a prime location in the search for life elsewhere in the solar system. Two landers are being proposed which would launch in 2020 and land about six years later.
As stated by Kevin Hand of JPL, “Europa, I think, is the premier place to go for extant life. Europa really does give us this opportunity to look for living life in the ocean that is there today, and has been there for much of the history of the solar system.”
While the landers wouldn’t be able to access the ocean water which is well below the surface, they could analyze the surface composition with a mass spectrometer, seismometers and cameras. The mass spectrometer could detect organics on the surface if there are any. The landers probably wouldn’t last too long though, because of the intense radiation from Jupiter on the unprotected surface (as Europa has only a very slight, tenuous atmosphere). Accessing any of the water from its ocean or lakes would require drilling deep down, something for a more advanced future mission.
Another mission being considered is a Europa orbiter, which could also launch in 2020. In some ways that might be even better, as it could provide a broader detailed study of the moon over a longer time period. Of course if both missions could be done, that would be fantastic, but budgets will probably only allow for one of them. The lander mission is estimated to probably cost about $800 million to $2 billion, while an orbiter would cost about $4.7 billion.
It might be noted that a return mission to Saturn’s moon Enceladus would also be possible, especially since the water from its subsurface ocean or sea (depending on the various working models of its interior and geology) can be sampled directly from its water vapour geysers, no need to drill down. The Cassini spacecraft has already done that more than once, and has found organics of various complexities, but Cassini’s instruments can’t detect life itself.
Either destination would be exciting, as both are thought to be two of the most likely places in the solar system, besides Earth of course, to be inhabitable or even possibly inhabited. Everywhere on Earth where there is water, there is life. That may or may not be true for Europa or Enceladus, but we’ll never know unless we look.
Stratolaunch Systems Carrier Aircraft - Air Launch to Orbit Space Launch System. Developed by Scaled Composites, the aircraft manufacturer and assembler founded by Burt Rutan. The carrier will loft and drop the 500,000 multistage SpaceX rocket that will propel payloads to orbit at dramatically reduced costs. It will be the largest aircraft ever flown with a wing span of 385 feet and weighing 1.2 million pounds. Credit: Stratolaunch Systems. Watch complete video below.
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A mega quartet of luminaries led by Microsoft co-founder Paul G. Allen and legendary aerospace designer Burt Rutan have joined forces to create a revolutionary new approach to space travel. This new privately funded venture entails the development of a mammoth air-launched space transportation system that aims to dramatically cut the high costs and risks of launching both cargo and human crews to low Earth orbit.
Allen and Rutan are teaming up with Elon Musk, founder of Space Exploration Technologies Corp, or SpaceX, and Michael Griffin, former NASA Administrator, to build the world’s largest aircraft ever flown and use it as a platform to loft a multi-stage SpaceX rocket that will deliver a payload of some 13,500 pounds into earth orbit, about the same class as a Delta II.
Allen and Rutan hope to build upon the spaceflight revolution that they pioneered with the suborbital SpaceShipOne in 2004, which was the first privately funded spaceship to reach the edge of space, and now take the critical next step and actually vault all the way to orbit.
Video Caption: Stratolaunch Systems is pioneering innovative solutions to revolutionize space transportation to orbit.
To accomplish this innovative leap, Allen and Rutan, announced the formation of a new company, funded by Allen, called Stratolaunch Systems at a press briefing today, Dec. 13, held in Seattle, WA. Allen is a billionaire and philanthropist who has funded a host of projects to advance science,
“Our national aspirations for space exploration have been receding,” Allen lamented at the start of the briefing. “This year saw the end of NASA’s space shuttle program. Constellation, which would have taken us back to the moon, has been mothballed as well. For the first time since John Glenn, America cannot fly its own astronauts into space.”
“With government funded spaceflight diminishing, there’s a much expanded opportunity for privately funded efforts.”
Rutan said that Stratolaunch will build a 1.2 million pound carrier aircraft sporting a wingspan of 385 feet – longer than a football field – and which will be powered by six 747 engines on takeoff. The carrier will be a twin fuselage vehicle, like the WhiteKnight developed by Rutan to launch SpaceShipOne.
Air launch of SpaceX rocket to orbit
The 120 foot long SpaceX rocket, weighing up to 490,000 pounds, will be slung in between and dropped at an altitude of about 30,000 feet for the remaining ascent to orbit.
SpaceX will construct a shorter, less powerful version of the firms existing Falcon 9 rocket, which may be either a Falcon 4 or Falcon 5 depending on specifications.
The new launch system will operate from a large airport or spaceport like the Kennedy Space Center, require a 12,000 feet long runway for takeoff and landing and be capable of flying up to 1,300 nautical miles to the payload’s launch point. Crews aboard the huge carrier aircraft will also conduct the countdown and firing of the booster and will monitor payload blasting to orbit.
“I have long dreamed about taking the next big step in private space flight after the success of SpaceShipOne – to offer a flexible, orbital space delivery system,” Allen said. “We are at the dawn of radical change in the space launch industry. Stratolaunch Systems is pioneering an innovative solution that will revolutionize space travel.”
The goal of Stratolaunch is to “bring airport-like operations to the launch of commercial and government payloads and, eventually, human missions,” according to a company statement.
Plans call for a first orbital flight within five years by around 2016. Test flights could begin around 2015.
“We believe this technology has the potential to someday make spaceflight routine by removing many of the constraints associated with ground launched rockets,” said Mike Griffin. “Our system will also provide the flexibility to launch from a large variety of locations.”
Mike Griffin added that the venture is aiming for the small to medium class payload market similar to what has been served by the venerable Delta II rocket, which is now being retired after decades of service.
“At some point this vehicle could loft a crew of say six people,” Griffin stated.
“This is an exciting day,” concluded Allen.
“Stratolaunch will keep America at the forefront of space exploration and give tomorrow’s children something to search for in the night sky and dream about. Work has already started on our project at the Mojave Spaceport.”
SpaceX Dragon cargo spaceship propels commercial and science payloads to orbit following air-launch from gigantic carrier aircraft. Credit: Stratolaunch Systems
Dawn Orbiting Vesta. This artist's concept shows NASA's Dawn spacecraft orbiting the giant asteroid Vesta. The depiction of Vesta is based on images obtained by Dawn's framing cameras. Dawn is an international collaboration of the US, Germany and Italy. Credit: NASA/JPL-Caltech
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NASA’s Dawn Asteroid Orbiter successfully spiraled down today to the closest orbit the probe will ever achieve around the giant asteroid Vesta, and has now begun critical science observations that will ultimately yield the mission’s highest resolution measurements of this spectacular body.
“What can be more exciting than to explore an alien world that until recently was virtually unknown!” Dr. Marc Rayman gushed in an exclusive interview with Universe Today. Rayman is Dawn’s Chief Engineer from NASA’s Jet Propulsion Lab (JPL) in Pasadena, Calif., and a protégé of Star Trek’s Mr. Scott.
Before Dawn, Vesta was little more than a fuzzy blob in the world’s most powerful telescopes. Vesta is the second most massive object in the main Asteroid Belt between Mars and Jupiter.
Dawn is now circling about Vesta at the lowest planned mapping orbit, dubbed LAMO for Low Altitude Mapping Orbit. The spacecraft is orbiting at an average altitude of barely 130 miles (210 kilometers) above the heavily bombarded and mysterious world that stems from the earliest eons of our solar system some 4.5 Billion years ago. Each orbit takes about 4.3 hours.
“It is both gratifying and exciting that Dawn has been performing so well,” Rayman told me.
Dawn Orbiting Over Vesta - A Hi Res Taste of What's Ahead!
This image of the giant asteroid Vesta was obtained by Dawn in the evening Nov. 27 PST (early morning Nov. 28, UTC), as it was spiraling down from its high altitude mapping orbit to low altitude mapping orbit. Low altitude mapping orbit is the closest orbit Dawn will be making, at an average of 130 miles (210 kilometers) above the giant asteroid's surface. The framing camera obtained this image of an area in the northern mid-latitudes of Vesta from an altitude of about 140 miles (230 kilometers). Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
Dawn arrived in orbit at Vesta in July 2011 after a nearly 4 year interplanetary cruise since blasting off atop a Delta II rocket from Cape Canaveral, Florida in September 2007. The probe then spent the first few weeks at an initial science survey altitude of about 1,700 miles (2,700 kilometers).
Gradually the spaceship spiraled down closer to Vesta using her ion propulsion thrusters.
See Vesta science orbit diagram, below, provided courtesy of Dr. Marc Rayman.
Along the way, the international science and engineering team commanded Dawn to make an intermediate stop this past Fall 2011 at the High Altitude Mapping orbit altitude (420 miles, or 680 kilometers).
“It is so cool now to have reached this low orbit [LAMO]. We already have a spectacular collection of images and other fascinating data on Vesta, and now we are going to gain even more,” Rayman told me.
“We have a great deal of work ahead to acquire our planned data here, and I’m looking forward to every bit!
Dawn will spend a minimum of 10 weeks acquiring data at the LAMO mapping orbit using all three onboard science instruments, provided by the US, Germany and Italy.
While the framing cameras (FC) from Germany and the Visible and Infrared Mapping spectrometer (VIR) from Italy will continue to gather mountains of data at their best resolution yet, the primary science focus of the LAMO orbit will be to collect data from the gamma ray and neutron detector (GRaND) and the gravity experiment.
GRaND will measure the elemental abundances on the surface of Vesta by studying the energy and neutron by-products that emanate from it as a result of the continuous bombardment of cosmic rays. The best data are obtained at the lowest altitude.
Dawn spacecraft - Science orbits at Vesta
Credit: NASA/JPL-Caltech/Marc Rayman
By examining all the data in context, scientists hope to obtain a better understanding of the formation and evolution of the early solar system.
Vesta is a proto-planet, largely unchanged since its formation, and whose evolution into a larger planet was stopped cold by the massive gravitational influence of the planet Jupiter.
“Dawn’s visit to Vesta has been eye-opening so far, showing us troughs and peaks that telescopes only hinted at,” said Christopher Russell, Dawn’s principal investigator, based at UCLA. “It whets the appetite for a day when human explorers can see the wonders of asteroids for themselves.”
After investigating Vesta for about a year, the engineers will ignite Dawn’s ion propulsion thrusters and blast away to Ceres, the largest asteroid which may harbor water ice and is another potential outpost for extraterrestrial life
Dawn will be the first spaceship to orbit two worlds and is also the first mission to study the asteroid belt in detail.
Asteroid Vesta from Dawn - Exquisite Clarity from a formerly Fuzzy Blob
NASA's Dawn spacecraft obtained this image of the giant asteroid Vesta with its framing camera on July 24, 2011. It was taken from a distance of about 3,200 miles (5,200 kilometers). Before Dawn, Vesta was just a fuzzy blob in the most powerful telescopes. Dawn entered orbit around Vesta on July 15, and will spend a year orbiting the body before firing up the ion propulsion system to break orbit and speed to Ceres, the largest Asteroid. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDASouth Polar Region of Vesta - Enhanced View
An ancient cosmic collision blasted away much of the south pole of Vesta, leaving behind an enoumous mountain about 3 times the height of Mt. Everest. NASA's Dawn spacecraft obtained this image centered on the south pole of Vesta with its framing camera on July 18, 2011 as it passed the terminator. The image has been enhanced to bring out more surface details. It was taken from a distance of about 6,500 miles (10,500 kilometers) away from the protoplanet Vesta. The smallest detail visible is about 1.2 miles (2.0 km). Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA. Enhanced and annotated by Ken Kremer
Read continuing features about Dawn by Ken Kremer starting here:
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:
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.
'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
