A newly released NASA video features MAVEN Deputy Project Manager Sandra Cauffman speaking in Spanish about her work on the mission. Released today with English subtitles, the video highlights Cauffman’s career at the NASA Goddard Space Flight Center and details her integral role in coordinating the MAVEN budget and schedule. The video is the first in a two-part Spanish-language series that aims to make MAVEN more accessible to Spanish-speaking communities.

The video compliments the MAVEN Red Planet: Read, Write, Explore! program, an educational project with a Spanish focus. The video may be particularly useful during Red Planet teacher training workshops, which target English as a Second Language, Spanish as a Second Language, and bilingual educators.

For more information about MAVEN Red Planet, please visit: http://lasp.colorado.edu/home/maven/education-outreach/for-educators/red-planet/.

This photo taken on March 3 shows the large hydrazine propellant tank prior to integration with the core structure of the MAVEN spacecraft at a Lockheed Martin clean room near Denver. The tank will hold 450 gallons of hydrazine propellant and is 6 feet 2 inches tall. The tank was built by ATK Aerospace Group, Commerce, Calif. The primary structure in the background is cube shaped at 7.5 feet x 7.5 feet x 6.5 feet high. Built out of composite panels comprised of aluminum honeycomb sandwiched between graphite composite face sheets, the entire structure only weighs 275 pounds. (Courtesy Lockheed Martin)

Lockheed Martin has installed the propellant tank on NASA’s MAVEN spacecraft, which it is building at its Space Systems Company facilities near Denver. In addition to the large tank, many of the primary propulsion components including all 20 of the spacecraft’s thrusters have been installed.

Mission Information

The goal of the Mars Atmosphere and Volatile EvolutioN (MAVEN) program is to determine the role that loss of atmospheric gas to space played in changing the Martian climate through time. MAVEN will determine how much of the Martian atmosphere has been lost over time by measuring the current rate of escape to space and gathering enough information about the relevant processes to allow extrapolation backward in time.

MAVEN’s principal investigator is based at the University of Colorado at Boulder’s Laboratory for Atmospheric and Space Physics. The university will provide science operations, build instruments, and lead Education/Public Outreach. NASA Goddard Space Flight Center in Greenbelt, Maryland, will manage the MAVEN mission and provide instruments. Lockheed Martin of Littleton, Colo., will build the spacecraft and perform mission operations. The University of California-Berkeley Space Sciences Laboratory will build instruments for the mission. NASA’s Jet Propulsion Laboratory, Pasadena, Calif., will provide Program management via the Mars Program Office, as well as navigation support, the Deep Space Network, and the Electra telecommunications relay hardware and operations.

To read the complete Lockheed Martin release, visit:
http://www.lockheedmartin.com/us/news/press-releases/2012/april/0416-ss-maven.html

Media Contacts

Gary Napier, Lockheed Martin Space Systems Company
(303) 971-4012; gary.p.napier@lmco.com

The MAVEN spacecraft core structure is lifted out of the reaction chamber after its static loads test. The structure provides the framework that supports all of the pieces that make up the MAVEN spacecraft. (Courtesy Lockheed Martin)

As I stood watching the static loads test of the MAVEN spacecraft structure, my thoughts went back to my high school physics class, where we built bridges out of balsa wood. To see which bridge was the strongest, the teacher applied a force to the center until the bridge broke. Each student would cringe as the pressure increased, waiting for the sound of splintering wood. I had that same feeling now.

The static test is one of the key tests for the structure. It’s designed to ensure that the structure will withstand the extreme forces of launch. The structure provides the framework that supports all of the pieces that together make up the MAVEN spacecraft. Science instruments, computers, batteries, radios, solar arrays, propulsion—nearly everything gets attached to the structure. It has to be strong enough to withstand the intense shaking and acceleration during launch, but light enough for a single Atlas V to lift it, and the other equipment, away from Earth and send it all the way to Mars. An all-metal structure would be too heavy, so we make it primarily out of composite panels. The core structure weighs less than an average NFL lineman, but it has to support a fully-fueled spacecraft weighing as much as a full size SUV, all while the rocket is accelerating it six times faster than a Ferrari.

The static test is conducted by using hydraulic rams to apply controlled force to critical points on the structure. Load cells, strain gages, and displacement transducers are used to precisely measure the effects. The forces we apply are higher than what we expect to actually see at launch. We always design and test with this margin because of the unexpected. The total forces from all of the rams we applied during the most stressing test exceeded 35 tons. The success criteria is simple: if the structure does not break and its deflections match our computer models, then we know it was properly designed and built correctly.

I listened to the groans of the structure as the test progressed and wondered if I would hear the sound of splintering composite panels, just like the sound of my bridge breaking all those years ago. I didn’t hear it. The structures team had done an outstanding job designing and building the structure, and we passed the test with flying colors. The structure was now ready to be handed over to the propulsion team so that they could start installing the fuel tanks, thrusters and propellant tubes. I could breathe a little easier, at least for awhile.

–Guy Beutelschies, MAVEN Flight Systems Manager, Lockheed Martin

MAVEN Principal Investigator Bruce Jakosky discusses the mission with Crum Middle School students during a visit in September 2011. (Courtesy Susan Sparacino)

In September, MAVEN Principal Investigator, Bruce Jakosky, and MAVEN Deputy Project Manager for Resources, Susan Sparacino, visited Crum Middle School and Tolsia High School in West Virginia. The visit represents one avenue through which the MAVEN team is bringing the science of the mission directly to a variety of public audiences.

Jakosky and Sparacino brought the science of MAVEN and the excitement of Mars exploration to rural middle and high school students. Over the course of two days, Jakosky and Sparacino visited a total of 12 science classrooms, reaching approximately 225 students.

At Crum Middle School, MAVEN team members worked primarily with science teacher Tara Crabtree and librarian Jamie Meddings, who are excited about the science of the MAVEN mission. Crum administrators have committed to using MAVEN as a theme for mandatory science fair projects this year; Meddings will serve as a resource to help connect students with available information and related content.

MAVEN will measure the upper atmosphere of Mars to determine the climate history of the planet. (Courtesy NASA/GSFC)

Maybe because it appears as a speck of blood in the sky, the planet Mars was named after the Roman god of war. From the point of view of life as we know it, that’s appropriate. The Martian surface is incredibly hostile for life. The Red Planet’s thin atmosphere does little to shield the ground against radiation from the Sun and space. Harsh chemicals, like hydrogen peroxide, permeate the soil. Liquid water, a necessity for life, can’t exist for very long here—any that does not quickly evaporate in the diffuse air will soon freeze out in subzero temperatures common over much of the planet.

It wasn’t always this way. There are signs that in the distant past, billions of years ago, Mars was a much more inviting place. Martian terrain is carved with channels that resemble dry riverbeds. Spacecraft sent to orbit Mars have identified patches of minerals that form only in the presence of liquid water. It appears that in its youth, Mars was a place that could have harbored life, with a thicker atmosphere warm enough for rain that formed lakes or even seas.

Two new NASA missions, one that will roam the surface and another that will orbit the planet and dip briefly into its upper atmosphere, will try to discover what transformed Mars. “The ultimate driver for these missions is the question, did Mars ever have life?” says Paul Mahaffy of NASA’s Goddard Space Flight Center in Greenbelt, Md. “Did microbial life ever originate on Mars, and what happened to it as the planet changed? Did it just go extinct, or did it go underground, where it would be protected from space radiation and temperatures might be warm enough for liquid water?”

The Mars Science Laboratory (MSL) mission features Curiosity, the largest and most advanced rover ever sent to the Red Planet. The Curiosity rover bristles with multiple cameras and instruments, including Goddard’s Sample Analysis at Mars (SAM) instrument suite. By looking for evidence of water, carbon, and other important building blocks of life in the Martian soil and atmosphere, SAM will help discover whether Mars ever had the potential to support life. Scheduled to launch in late November or December 2011, Curiosity will be delivered to Gale crater, a 96-mile-wide crater that contains a record of environmental changes in its sedimentary rock, in August 2012.

The Mars Atmosphere and Volatile EvolutioN (MAVEN) mission, scheduled to launch in late 2013, will orbit Mars and is devoted to understanding the Red Planet’s upper atmosphere. It will help determine what caused the Martian atmosphere—and water— to be lost to space, making the climate increasingly inhospitable for life.

“Both MAVEN and Curiosity/SAM will determine the history of the Martian climate and atmosphere using multiple approaches,” said MAVEN Principal Investigator Bruce Jakosky of the University of Colorado’s Laboratory for Atmospheric and Space Physics. “Measurements of isotope ratios are an approach shared by both missions.”

Isotopes are heavier versions of an element. For example, deuterium is a heavy version of hydrogen. Normally, two atoms of hydrogen join to an oxygen atom to make a water molecule, but sometimes the heavy (and rare) deuterium takes a hydrogen atom’s place.

When water gets lofted into Mars’ upper atmosphere, solar radiation can break it apart into hydrogen (or deuterium) and oxygen. Hydrogen escapes faster because it is lighter than deuterium. Since the lighter version escapes more often, over time, the Martian atmosphere has less and less hydrogen compared to the amount of deuterium remaining. The Martian atmosphere therefore becomes richer and richer in deuterium.

The MAVEN team will measure the amount of deuterium compared to the amount of hydrogen in Mars’ upper atmosphere, which is the planet’s present-day deuterium to hydrogen (D/H) ratio. They will compare it to the ratio Mars had when it was young—the early D/H ratio. (The early ratio can be measured from the D/H ratio in ancient Martian minerals and estimated from observations of the D/H ratio in comets and asteroids, which are believed to be pristine, “fossil” remnants of our solar system’s formation.)

Comparing the present and early D/H ratios will allow the team to calculate how much hydrogen (and, therefore, water) has been lost over Mars’ lifetime. MAVEN will also determine how much Martian atmosphere has been lost over time by measuring the isotope ratios of other elements in the very high atmosphere, such as nitrogen, oxygen, carbon, and noble gases like argon.

MAVEN is expected to reach Mars in 2014. By then, SAM on board the Curiosity rover will have made similar measurements from Gale crater, which will help guide the interpretation of MAVEN’s upper atmosphere measurements.

Measuring isotopes in the atmosphere will reveal its present state. To find out what the Martian atmosphere was like in the past, scientists will use what they discover with MAVEN about the various ways the atmosphere is being removed. With that data, they will build computer simulations, or models, to estimate the condition of the Red Planet’s atmosphere billions of years ago.

Scientists estimate Gale crater may have formed more than three billion years ago. Curiosity will grind up Gale crater minerals and deliver them to SAM so the isotope ratios can be measured, giving a glimpse at the Martian atmosphere from long ago, perhaps when it could have supported life. “SAM’s inputs from the surface of past Martian history will help the MAVEN team work backwards to discover how the Martian atmosphere evolved,” said Joseph Grebowsky of NASA Goddard, MAVEN Project Scientist.

“For example, MAVEN will focus primarily on how solar activity erodes the Martian atmosphere,” adds Mahaffy. Things like the solar wind, a tenuous stream of electrically conducting gas blown from the surface of the Sun, and explosions in the Sun’s atmosphere called solar flares, and eruptions of solar material called coronal mass ejections can all strip away the upper atmosphere of Mars in various ways. “If we figure out how much atmosphere is removed by changes in solar activity, we can extrapolate back to estimate what the isotope ratios should have been billions of years ago. However, if the measurements of the ancient ratios from SAM don’t match up, this suggests that we may have to look at other ways the atmosphere could have been lost, such as giant impacts from asteroids,” says Mahaffy, who is Principal Investigator for SAM and Instrument Lead for the Neutral Gas and Ion Mass Spectrometer instrument on MAVEN. Some scientists believe giant impacts could have blasted significant amounts of the Martian atmosphere into space.

Also, Curiosity will carry a weather station, which will help the MAVEN team understand how changes in the upper atmosphere are related to changes at the surface. “For example, if the rover detects a dust storm, it may have an effect higher up because of the winds and the gravity waves (the bobbing up and down of a parcel of air) it sets up,” says Grebowsky.

“Curiosity will focus on geology and minerals to determine if the environment on Mars in the distant past had the potential to support life,” said Mahaffy. “It will be digging in the dirt trying to understand the habitability issue in a place where water may have flowed, where there could have been a lake. Habitability is also the basic theme of MAVEN—it will be trying to understand from the top down how the atmosphere evolved over time and how it was lost, which ties back to how clement it was early on.”

MAVEN is part of NASA’s Mars Scout program, funded by NASA Headquarters, Washington, D.C. The project is led out of the University of Colorado and managed by NASA Goddard. The Mars Science Laboratory is managed for NASA’s Science Mission Directorate, Washington, D.C., by NASA’s Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena.

Bill Steigerwald
NASA’s Goddard Space Flight Center, Greenbelt, Md.

To read the original NASA feature story, visit http://www.nasa.gov/topics/solarsystem/features/hostile_mars.html.

Technicians from Lockheed Martin inspect the MAVEN primary structure following its completion at the company’s Composites Lab in this Sept. 8, 2011 photo. (Courtesy Lockheed Martin)

NASA’s Mars Atmosphere and Volatile EvolutioN (MAVEN) mission has reached a new milestone. Lockheed Martin has completed building the primary structure of the MAVEN spacecraft at its Space Systems Company facility near Denver. The MAVEN spacecraft is scheduled to launch in November 2013 and will be the first mission devoted to understanding the Martian upper atmosphere. The mission’s principal investigator is Bruce Jakosky from the Laboratory for Atmospheric and Space Physics at the University of Colorado.

In the photo taken on Sept. 8, technicians from Lockheed Martin are inspecting the MAVEN primary structure following its recent completion at the company’s Composites Lab. The primary structure is cube shaped at 7.5 feet x 7.5 feet x 6.5 feet high (2.3 meters x 2.3 meters x 2 meters high). Built out of composite panels comprised of aluminum honeycomb sandwiched between graphite composite face sheets and attached to one another with metal fittings, the entire structure only weighs 275 pounds (125 kilograms). At the center of the structure is the 4.25 feet (1.3 meters) diameter core cylinder that encloses the hydrazine propellant tank and serves as the primary vertical load-bearing structure. The large tank will hold approximately 3,615 pounds (1640 kilograms) of fuel.

“It’s always a significant milestone when the project moves from a paper design to real hardware and software,” said Guy Beutelschies, MAVEN program manager at Lockheed Martin Space Systems Company. “Seeing the core structure really reinforces the fact that MAVEN is no longer just a set of ideas that scientists and engineers have come up with, it is starting to become a spacecraft.”

In mid October, the structure will be moved to Lockheed Martin’s Structures Test Lab and undergo static load testing, which simulates and tests the many dynamic loads the spacecraft will experience during launch.

Despite the primary structure’s light weight, it’s designed to support the entire spacecraft mass during the launch, which applies an equivalent axial force at the launch vehicle interface of approximately 61,000 pounds when including accelerations up to 6 Gs. After completion of the static tests, the structure will be moved into a clean room to start propulsion subsystem integration. The Assembly, Test and Launch Operations (ATLO) phase begins July 2012.

“There’s still a lot of work to go before we have the complete spacecraft, but this is a major step in getting us to the launch pad in two years,” said Bruce Jakosky, MAVEN principal investigator from the Laboratory for Atmospheric and Space Physics at the University of Colorado. “All of the team’s hard work now will pay off when we get to Mars and see the science results.”

The goal of MAVEN is to determine the role that loss of atmospheric gas to space played in changing the Martian climate through time. MAVEN will determine how much of the Martian atmosphere has been lost over time by measuring the current rate of escape to space and gathering enough information about the relevant processes to allow extrapolation backward in time.

NASA Goddard Space Flight Center in Greenbelt, Md. manages the project and will also build some of the instruments for the mission. In addition to the principal investigator coming from CU-LASP, the university will provide science operations, build instruments, and lead education/public outreach. Lockheed Martin of Littleton, Colo., is building the spacecraft and will perform mission operations. The University of California-Berkeley Space Sciences Laboratory is also building instruments for the mission. NASA’s Jet Propulsion Laboratory, Pasadena, Calif., will provide navigation support, the Deep Space Network, and the Electra telecommunications relay hardware and operations.

To view the full NASA press release, please visit: http://www.nasa.gov/mission_pages/maven/news/maven-structure.html

To view the Lockheed Martin press release, please visit: http://www.lockheedmartin.com/us/news/press-releases/2011/september/LockheedMartinCompletesPr.html

The Mars Atmosphere and Volatile Evolution (MAVEN) mission will be the first mission devoted to understanding the Martian upper atmosphere. (Courtesy NASA/GSFC)

The CU/LASP-led mission to Mars, devoted to understanding the Martian upper atmosphere, reached a major milestone last week when it successfully completed its Mission Critical Design Review (CDR) at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

An independent review board, comprised of reviewers from NASA and several external organizations, met from July 11-15 to validate the system design of the Mars Atmosphere and Volatile Evolution, or MAVEN, mission.

The CDR bridges the design and manufacturing stages of a project. A successful review means that the design is validated and will meet its requirements, is backed up with solid analysis and documentation, and has been proven to be safe. Completing the CDR grants permission to the mission team to begin manufacturing hardware.

The goal of MAVEN is to determine the role that loss of atmospheric gas to space played in changing the Martian climate through time. MAVEN will determine how much of the Martian atmosphere has been lost over time by measuring the current rate of escape to space and gathering enough information about the relevant processes to allow extrapolation backward in time.

LASP is leading the mission, which will carry three instrument suites to probe the atmosphere of Mars and its interactions with the sun. LASP Associate Director and CU professor Bruce Jakosky is the principal investigator for MAVEN.

“The Critical Design Review is a real benchmark for the MAVEN team as we progress toward launch,” said Jakosky. “We are on schedule and on track, which is good news and a tribute to the hard work by all of the MAVEN team members.” MAVEN is scheduled to launch in late November, 2013.

The three instrument suites on MAVEN will include a remote sensing package, built by LASP, that will determine global characteristics of the upper atmosphere and ionosphere. The MAVEN science team includes three LASP scientists heading up instrument teams—Nick Schneider, Robert Ergun, and Frank Eparvier—as well as a large supporting team of scientists, engineers and missions operations specialists.

The LASP team will also provide science operations, build two of the science instruments and lead education and public outreach efforts for the MAVEN mission. NASA Goddard is managing the project and Lockheed Martin, based in Littleton, Colorado, is building the spacecraft.

The MAVEN effort also includes participation by a number of CU graduate and undergraduate students. Currently there are more than 100 students working on research projects at LASP, which provides training for future careers as engineers and scientists.

To view the CU-Boulder press release, visit:
http://www.colorado.edu/news/r/0bff695f6804a80b842c21a06bc7b17d.html

To view the NASA press release, visit:
http://www.nasa.gov/mission_pages/maven/news/maven-cdr.html

The Atlas V launch site can be viewed in this photo from the top of the Vertical Integration Facility. (Courtesy ULA)

NASA has selected United Launch Services, LLC of Littleton, Colo., to launch the Mars Atmosphere and Volatile Evolution spacecraft known as MAVEN. MAVEN will launch in November 2013 aboard an Atlas V 401 rocket from Complex 41 at Cape Canaveral Air Force Station, Fla.

The total cost value for the MAVEN launch service is approximately $187 million. This estimated cost includes the task ordered launch service for the Atlas plus additional services under other contracts for payload processing; launch vehicle integration; mission unique launch site ground support; and tracking, data and telemetry services.

MAVEN is a Mars orbiter that will greatly enhance our understanding of Mars’ climate history by providing a comprehensive picture of the planet’s upper atmosphere, ionosphere, solar energy drivers and atmospheric losses.

NASA’s Goddard Space Flight Center in Greenbelt, Md., manages the MAVEN project. MAVEN’s principal investigator is based at the University of Colorado at Boulder’s Laboratory for Atmospheric and Space Physics. The Launch Services Program at NASA’s Kennedy Space Center in Florida is responsible for launch vehicle program management of the Atlas V launch services. United Launch Alliance provides the launch services for United Launch Services.

To read the original NASA press release, visit:

http://www.nasa.gov/home/hqnews/2010/oct/HQ_C10-065_Maven_Services.html

The LASP-led Mars Atmosphere and Volatile Evolution (MAVEN) mission launches in November 2013. (Courtesy NASA/JPL)

The effort, known as the Mars Atmosphere and Volatile Evolution, or MAVEN, mission, will explore the past climate of Mars, including its potential for harboring life over the ages. LASP is leading the mission, which will carry three instrument suites to probe the atmosphere of Mars and its interactions with the sun. LASP Associate Director and CU professor Bruce Jakosky is principal investigator on the mission.

Jakosky said, “A better understanding of the upper atmosphere and the loss of volatile compounds like carbon dioxide, nitrogen dioxide and water to space is required to plug a major hole in our understanding of Mars. We’re really excited about having the opportunity to address these fundamental science questions.”

The LASP team also will provide science operations, build two of the science instruments and lead education and public outreach efforts for the MAVEN mission.

Clues on the Martian surface, including features resembling dry riverbeds and minerals that only form in the presence of water, suggest Mars once had a denser atmosphere that supported the presence of liquid water on the surface. Since most of the atmosphere was lost as part of a dramatic climate change, MAVEN will make definitive scientific measurement of present-day atmospheric loss that will offer insight into the Red Planet’s history.

Michael Luther, on behalf of Ed Weiler of the NASA Headquarters Science Mission Directorate, led a confirmation review panel that approved the detailed plan, instrument suite and budget for the mission.

MAVEN Project Manager David Mitchell, of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, said, “The team has successfully met every major milestone since selection two years ago. Looking forward, we are well positioned for the next push to critical design review in July 2011. In three short years we will be heading to Mars.” Launch is scheduled for November of 2013.

The three instrument suites on MAVEN will include a remote sensing package built by LASP that will determine global characteristics of the upper atmosphere. The MAVEN science team includes three LASP scientists heading up instrument teams—Nick Schneider, Frank Eparvier, and Robert Ergun—as well as a large supporting team of scientists, engineers and missions operations specialists.

The MAVEN effort also will include participation by a number of CU graduate and undergraduate students in the coming years, said Jakosky. Currently there are more than 100 students working on research projects at LASP, which provides training for future careers as engineers and scientists.

The confirmation review announced today authorized continuation of the project and set its cost and schedule. The next major mission milestone, the critical design review, will examine the detailed MAVEN system design. Assuming the critical design review is successful, the project team will assemble the spacecraft and its instruments.

The MAVEN contract is the largest ever awarded to CU-Boulder. NASA Goddard will manage the project, which will cost $438 million excluding the separately funded government-furnished launch vehicle and telecommunications relay package. Goddard also is building several science instruments for the mission.

Lockheed Martin of Littleton, Colorado, will build the spacecraft based on designs from NASA’s Mars Reconnaissance Orbiter and 2001 Mars Odyssey missions as well as perform mission operations. The University of California-Berkeley Space Sciences Laboratory also will build instruments for the mission and support education and public outreach efforts.

NASA’s Jet Propulsion Laboratory in Pasadena, California, will provide navigation support, the Deep Space Network, and the Electra telecommunications relay hardware and operations.

To view Lockheed Martin’s press release, visit:

http://www.lockheedmartin.com/news/press_releases/2010/1005_ss_maven.html

To view NASA’s Goddard Space Flight Center’s press release, visit:

http://www.nasa.gov/centers/goddard/news/releases/2010/10-087.html

In the upper left of this Hubble Space Telescope image, at high northern latitudes, a large chevron-shaped area of water ice clouds mark a storm front. Along the right limb, a large cloud system has formed around the Olympus Mons volcano. (Courtesy NASA)

The Red Planet bleeds. Not blood, but its atmosphere, slowly trickling away to space. The culprit is our sun, which is using its own breath, the solar wind, and its radiation to rob Mars of its air. The crime may have condemned the planet’s surface, once apparently promising for life, to a cold and sterile existence.

Features on Mars resembling dry riverbeds, and the discovery of minerals that form in the presence of water, indicate that Mars once had a thicker atmosphere and was warm enough for liquid water to flow on the surface. However, somehow that thick atmosphere got lost in space. It appears Mars has been cold and dry for billions of years, with an atmosphere so thin, any liquid water on the surface quickly boils away while the sun’s ultraviolet radiation scours the ground.

Such harsh conditions are the end of the road for known forms of life. Although it’s possible that Martian life went underground, where liquid water may still exist and radiation can’t reach.

The lead suspect for the theft is the sun, and its favorite M.O. may be the solar wind. All planets in our solar system are constantly blasted by the solar wind, a thin stream of electrically charged gas that continuously blows from the sun’s surface into space. On Earth, our planet’s global magnetic field shields our atmosphere by diverting most of the solar wind around it. The solar wind’s electrically charged particles, ions and electrons, have difficulty crossing magnetic fields.

“Mars can’t protect itself from the solar wind because it no longer has a shield, the planet’s global magnetic field is dead,” said Bruce Jakosky of the University of Colorado, Boulder. Jakosky is the Principal Investigator for NASA’s MAVEN mission, which will investigate what is responsible for the loss of the Martian atmosphere. NASA selected the MAVEN (Mars Atmosphere and Volatile Evolution Mission) on September 15, 2008.

Mars lost its global magnetic field in its youth billions of years ago. Once its planet-wide magnetic field disappeared, Mars’ atmosphere was exposed to the solar wind and most of it could have been gradually stripped away. “Fossil” magnetic fields remaining in ancient surfaces and other local areas on Mars don’t provide enough coverage to shield much of the atmosphere from the solar wind.

Although the solar wind might be the primary method, like an accomplished burglar, the sun’s emissions can steal the Martian atmosphere in many ways. However, most follow a basic M.O., the solar wind and the sun’s ultraviolet radiation turns the uncharged atoms and molecules in Mars’ upper atmosphere into electrically charged particles (ions). Once electrically charged, electric fields generated by the solar wind carry them away. The electric field is produced by the motion of the charged, electrically conducting solar wind across the interplanetary, solar-produced magnetic field, the same dynamic generators use to produce electrical power.

An exception to this dominant M.O. are atoms and molecules that have enough speed from solar heating to simply run away, they remain electrically neutral, but become hot enough to escape Mars’ gravity. Also, solar extreme ultraviolet radiation can be absorbed by molecules, breaking them into their constituent atoms and giving each atom enough energy that it might be able to escape from the planet.

There are other suspects. Mars has more than 20 ancient craters larger than 600 miles across, scars from giant impacts by asteroids the size of small moons. This bombardment could have blasted large amounts of the Martian atmosphere into space. However, huge Martian volcanoes that erupted after the impacts, like Olympus Mons, could have replenished the Martian atmosphere by venting massive amounts of gas from the planet’s interior.

It’s possible that the hijacked Martian air was an organized crime, with both impacts and the solar wind contributing. Without the protection of its magnetic shield, any replacement Martian atmosphere that may have issued from volcanic eruptions eventually would also have been stripped away by the solar wind.

Earlier Mars spacecraft missions have caught glimpses of the heist. For example, flows of ions from Mars’ upper atmosphere have been seen by both NASA’s Mars Global Surveyor and the European Space Agency’s Mars Express spacecraft.

“Previous observations gave us ‘proof of the crime’ but only provided tantalizing hints at how the sun pulls it off — the various ways Mars can lose its atmosphere to solar activity,” said Joseph Grebowsky of NASA’s Goddard Space Flight Center in Greenbelt, Md. “MAVEN will examine all known ways the sun is currently swiping the Martian atmosphere, and may discover new ones as well. It will also watch how the loss changes as solar activity changes over a year. Linking different loss rates to changes in solar activity will let us go back in time to estimate how quickly solar activity eroded the Martian atmosphere as the sun evolved.” Grebowsky is the Project Scientist for MAVEN.

As the Martian atmosphere thinned, the planet got drier as well, because water vapor in the atmosphere was also lost to space, and because any remaining water froze out as the temperatures dropped when the atmosphere disappeared. MAVEN can discover how much water has been lost to space by measuring hydrogen isotope ratios.

Isotopes are heavier versions of an element. For example, deuterium is a heavy version of hydrogen. Normally, two atoms of hydrogen join to an oxygen atom to make a water molecule, but sometimes the heavy and rare, deuterium takes a hydrogen atom’s place.

On Mars, hydrogen escapes faster because it is lighter than deuterium. Since the lighter version escapes more often, over time, the Martian atmosphere has less and less hydrogen compared to the amount of deuterium remaining. The Martian atmosphere therefore becomes richer and richer in deuterium.

The MAVEN team will measure the amount of hydrogen compared to the amount of deuterium in Mars’ upper atmosphere, which is the planet’s present-day hydrogen to deuterium (H/D) ratio. They will compare it to the ratio Mars had when it was young — the original H/D ratio. The original ratio is estimated from observations of the H/D ratio in comets and asteroids, which are believed to be pristine, “fossil” remnants of our solar system’s formation.

Comparing the present and original H/D ratios will allow the team to calculate how much hydrogen, and therefore water, has been lost over Mars’ lifetime. For example, if the team discovers the Martian atmosphere is ten times richer in deuterium today, the planet’s original quantity of water must have been at least ten times greater than that seen today.

MAVEN will also help determine how much Martian atmosphere has been lost over time by measuring the isotope ratios of other elements in the air, such as nitrogen, oxygen, and carbon.

MAVEN is scheduled for launch between November 18 and December 7, 2013. If it is launched November 18, it will arrive at Mars on September 16, 2014 for its year-long mission.

MAVEN is part of NASA’s Mars Scout program, funded by NASA Headquarters in Washington, DC. The University of Colorado will coordinate the science team and science operations. NASA Goddard will manage the project and provide mission systems engineering, mission design, and safety and mission assurance. NASA’s Jet Propulsion Laboratory, Pasadena, Calif., will navigate the spacecraft, provide the Deep Space Network, and an Electra telecommunications relay package. Instruments on the spacecraft will be provided by the University of California, Berkeley, the University of Colorado, Boulder, and NASA Goddard, with the Centre d’Etude Spatiale des Rayonnements, Toulouse, France, providing the sensor for one instrument. Lockheed Martin Corp., Bethesda, Md., will develop the spacecraft, conduct assembly, test and launch operations, and provide mission operations at their Littleton, Colorado facility.

To read the original NASA feature story, visit:
http://www.nasa.gov/mission_pages/maven/news/confirmation.html