Msl landing

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Msl landing

  1. 1. Press Kit/JULY 2012Mars Science Laboratory Landing
  2. 2. Media ContactsDwayne Brown NASA’s Mars 202-358-1726Steve Cole Program 202-358-0918Headquarters dwayne.c.brown@nasa.govWashington stephen.e.cole@nasa.govGuy Webster Mars Science Laboratory 818-354-5011D.C. Agle Mission 818-393-9011Jet Propulsion Laboratory guy.webster@jpl.nasa.gov Pasadena, Calif. agle@jpl.nasa.gov Science Payload InvestigationsAlpha Particle X-ray Spectrometer: Ruth Ann Chicoine, Canadian Space Agency, Saint-Hubert, Québec,Canada; 450-926-4451; ruthann.chicoine@asc-csa.gc.caChemistry and Camera: James Rickman, Los Alamos National Laboratory, Los Alamos, N.M.; 505-665-9203;elvis@lanl.govChemistry and Mineralogy: Rachel Hoover, NASA Ames Research Center, Moffett Field, Calif.; 650-604-0643;rachel.hoover@nasa.govDynamic Albedo of Neutrons: Igor Mitrofanov, Space Research Institute, Moscow, Russia;011-7-495-333-3489; imitrofa@space.ruMars Descent Imager, Mars Hand Lens Imager, Mast Camera: Michael Ravine, Malin Space ScienceSystems, San Diego; 858-552-2650 extension 591; ravine@msss.comRadiation Assessment Detector: Donald Hassler, Southwest Research Institute; Boulder, Colo.;303-546-0683; hassler@boulder.swri.eduRover Environmental Monitoring Station: Luis Cuesta, Centro de Astrobiología, Madrid, Spain;011-34-620-265557; cuestacl@cab.inta-csic.esSample Analysis at Mars: Nancy Neal Jones, NASA Goddard Space Flight Center, Greenbelt, Md.;301-286-0039; nancy.n.jones@nasa.gov Engineering InvestigationMSL Entry, Descent and Landing Instrument Suite: Kathy Barnstorff, NASA Langley Research Center,Hampton, Va.; 757-864-9886; kathy.barnstorff@nasa.gov
  3. 3. ContentsMedia Services Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Quick Facts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Mars at a Glance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Mars Science Laboratory Investigations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Mission Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Comparing Two Mars Rover Projects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Spacecraft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Curiosity’s Landing Site . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46Recent, Current and Upcoming Missions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Mars Science: A Story of Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54Historical Mars Missions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59Program and Project Management. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61
  4. 4. Media Services InformationNASA Television Transmission Propulsion Laboratory, Pasadena, Calif., will present in- formation about the mission’s science goals and capa-NASA Television is available in continental North bilities at 10 a.m. PDT, and about the flight and plannedAmerica, Alaska and Hawaii by C-band signal via landing at 11 a.m. Pre-landing update briefings at JPLSatellite AMC-18C, at 105 degrees west longitude, are scheduled for 9:30 a.m. PDT on Aug. 4 and 9:30transponder 3C, 3760 MHz, vertical polarization. A a.m. on Aug. 5. A post-launch briefing at JPL will beginDigital Video Broadcast-compliant Integrated Receiver within about an hour of the anticipated landing timeDecoder is needed for reception. Transmission format (10:31 p.m. PDT) under most conditions, and withinis DVB-S, 4:2:0. Data rate is 38.80 Mbps; symbol rate about three hours of the landing time if the spacecraft’s28.0681, modulation QPSK/DVB-S, FEC 3/4. status is unknown. All of these briefings will be carried on NASA TV and on http://www.ustream.tv/nasajpl.NASA-TV Multichannel Broadcast includes: Public Specific information about upcoming briefings, as theyChannel (Channel 101) in high definition; Education are scheduled, will be kept current on the Internet atChannel (Channel 102) in standard definition; and Media http://www.nasa.gov/msl.Channel (Channel 103) in high definition. Live FeedFor digital downlink information for each NASA TV chan-nel, access to all three channels online, and a schedule Two live feeds of video during key landing activitiesof programming for Mars Science Laboratory activities, from mission control rooms at JPL will be carried onvisit http://www.nasa.gov/ntv. NASA TV and on http://www.ustream.tv between 8:30 and 11:00 p.m. PDT on Aug. 5 (11:30 p.m. Aug. 5 toMedia Credentialing 2:00 a.m. Aug. 6 EDT), and between 12:30 and 1:30 a.m. PDT on Aug. 6 (3:30 to 4:30 a.m. EDT).News media representatives who would like to cover The NASA TV Public Channel and http://www.ustream.the launch in person must be accredited through the tv/nasajpl will carry a feed including commentary andNASA Jet Propulsion Laboratory’s Media Relations interviews. The NASA TV Media Channel and http://Office. To apply for credentials, visit http://media- www.ustream.tv/nasajpl2 will carry an uninterrupted,credentials.jpl.nasa.gov. Specific questions about the clean feed.credentialing process may be submitted to media-credentials@list.jpl.nasa.gov. Journalists may con- Internet Informationtact the JPL newsroom at 818-354-5011 for moreinformation. Information about NASA’s Mars Science Laboratory mission, including an electronic copy of this press kit,News Conferences press releases, status reports and images, is available at http://www.nasa.gov/mars and http://marsprogram.An overview of the mission will be presented in a news jpl.nasa.gov/msl. Frequent updates about the mission,conference broadcast on NASA TV and on http://www. together with public feedback, are available by follow-ustream.tv/nasajpl, originating from NASA Headquarters ing Curiosity on Twitter at http://www.twitter.com/in Washington, at 1 p.m. EDT on July 16, 2012. Back- marscuriosity and on Facebook at http://www.to-back briefings on Aug. 2, 2012, at NASA’s Jet facebook.com/marscuriosity.Mars Science Laboratory Landing 5 Press Kit
  5. 5. Quick FactsSpacecraft MissionCruise vehicle dimensions (cruise stage and aeroshell Time of Mars landing: 10:31 p.m. Aug. 5 PDT (1:31with rover and descent stage inside): Diameter: 14 feet, a.m. Aug. 6 EDT, 05:31 Aug. 6 Universal Time) plus or9 inches (4.5 meters); height: 9 feet, 8 inches (3 meters) minus a minute. This is Earth-received time, which in- cludes one-way light time for radio signal to reach EarthRover name: Curiosity from Mars. The landing will be at about 3 p.m. localRover dimensions: Length: 9 feet, 10 inches (3.0 meters) time at the Mars landing site.(not counting arm); width: 9 feet, 1 inch (2.8 meters); Landing site: 4.6 degrees south latitude, 137.4 degreesheight at top of mast: 7 feet (2.1 meters); arm length: east longitude, near base of Mount Sharp inside Gale7 feet (2.1 meters); wheel diameter: 20 inches (0.5 Cratermeter) Earth–Mars distance on landing day: 154 million milesMass: 8,463 pounds (3,893 kilograms) total at launch, (248 million kilometers)consisting of 1,982-pound (899-kilogram) rover;5,293-pound (2,401-kilogram) entry, descent and land- One-way radio transit time, Mars to Earth, on landinging system (aeroshell plus fueled descent stage); and day: 13.8 minutes1,188-pound (539-kilogram) fueled cruise stage Total distance of travel, Earth to Mars: About 352 millionPower for rover: Multi-mission radioisotope thermoelec- miles (567 million kilometers)tric generator and lithium-ion batteries Primary mission: One Martian year (98 weeks)Science payload: 165 pounds (75 kilograms) in 10 in-struments: Alpha Particle X-ray Spectrometer, Chemistry Expected near-surface atmospheric temperatures atand Camera, Chemistry and Mineralogy, Dynamic landing site during primary mission: minus 130 F to 32Albedo of Neutrons, Mars Descent Imager, Mars Hand F (minus 90 C to zero C)Lens Imager, Mast Camera, Radiation Assessment ProgramDetector, Rover Environmental Monitoring Station, andSample Analysis at Mars Cost: $2.5 billion, including $1.8 billlion for spacecraftLaunch development and science investigations and additional amounts for launch and operations.Launch Time and Place: Nov. 26, 2011, 10:02 a.m.EST, from Launch Complex 41, Cape Canaveral AirForce Station, Fla.Launch Vehicle: Atlas V 541 provided by United LaunchAllianceEarth–Mars distance at launch: 127 million miles(204 million kilometers)Mars Science Laboratory Landing 6 Press Kit
  6. 6. Mars at a GlanceGeneral Environment• One of five planets known to ancients; Mars was • Atmosphere composed chiefly of carbon dioxide the Roman god of war, agriculture and the state (95.3 percent), nitrogen (2.7 percent) and argon• Yellowish brown to reddish color; occasionally the (1.6 percent) third-brightest object in the night sky after the moon • Surface atmospheric pressure less than 1/100th and Venus that of Earth’s average • Surface winds of 0 to about 20 miles per hour (0 toPhysical Characteristics about 9 meters per second), with gusts of about 90 miles per hour (about 40 meters per second)• Average diameter 4,212 miles (6,780 kilometers); • Local, regional and global dust storms; also whirl- about half the size of Earth, but twice the size of winds called dust devils Earth’s moon • Surface temperature averages minus 64 F (minus• Same land area as Earth, reminiscent of a cold, 53 C); varies from minus 199 F (minus 128 C) rocky desert during polar night to 80 F (27 C) at equator during• Mass 1/10th of Earth’s; gravity only 38 percent as midday at closest point in orbit to sun strong as Earth’s• Density 3.9 times greater than water (compared with Features Earth’s 5.5 times greater than water)• No planet-wide magnetic field detected; only local- • Highest point is Olympus Mons, a huge shield vol- ized ancient remnant fields in various regions cano about 16 miles (26 kilometers) high and 370 miles (600 kilometers) across; has about the same area as ArizonaOrbit • Canyon system of Valles Marineris is largest and• Fourth planet from the sun, the next beyond Earth deepest known in solar system; extends more than 2,500 miles (4,000 kilometers) and has 3 to 6 miles• About 1.5 times farther from the sun than Earth is (5 to 10 kilometers) relief from floors to tops of sur-• Orbit elliptical; distance from sun varies from a mini- rounding plateaus mum of 128.4 million miles (206.7 million kilometers) to a maximum of 154.8 million miles (249.2 million Moons kilometers); average is 141.5 million miles (227.7 million kilometers) • Two irregularly shaped moons, each only a few• Revolves around sun once every 687 Earth days kilometers wide• Rotation period (length of day): 24 hours, 39 min- • Larger moon named Phobos (“fear”); smaller is utes, 35 seconds (1.027 Earth days) Deimos (“terror”), named for attributes personified• Poles tilted 25 degrees, creating seasons similar to in Greek mythology as sons of the god of war Earth’sMars Science Laboratory Landing 7 Press Kit
  7. 7. Mars Science Laboratory InvestigationsMars Science Laboratory Investigations croorganisms or their fossil equivalents. However, if this mission finds that the field site in Gale Crater has hadNASA’s Mars Science Laboratory mission will study conditions favorable for habitability and for preservingwhether the Gale Crater area of Mars has evidence of evidence about life, those findings can shape futurepast and present habitable environments. These studies missions that would bring samples back to Earth forwill be part of a broader examination of past and present life-detection tests or for missions that carry advancedprocesses in the Martian atmosphere and on its surface. life-detection experiments to Mars. In this sense, theThe research will use 10 instrument-based science Mars Science Laboratory is the prospecting stage in ainvestigations. The mission’s rover, Curiosity, carries the step-by-step program of exploration, reconnaissance,instruments for these investigations and will support their prospecting and mining evidence for a definitive an-use by providing overland mobility, sample-acquisition swer about whether life has existed on Mars. NASA’scapabilities, power and communications. The primary Astrobiology Program has aided in development of themission will last one Mars year (98 weeks). Mars Science Laboratory science payload and in stud- ies of extreme habitats on Earth that can help in under-The payload includes mast-mounted instruments to standing possible habitats on Mars.survey the surroundings and assess potential samplingtargets from a distance; instruments on Curiosity’s Three conditions considered crucial for habitability arerobotic arm for close-up inspections; laboratory instru- liquid water, other chemical ingredients utilized by lifements inside the rover for analysis of samples from and a source of energy. The Mars Science Laboratoryrocks, soils and atmosphere; and instruments to moni- mission advances the “follow the water” strategy oftor the environment around the rover. In addition to the NASA Mars exploration since the mid-1990s to ascience payload, engineering sensors on the heat shield strategy of determining the best settings for seeking anwill gather information about Mars’ atmosphere and the answer to whether Mars ever supported life.spacecraft’s performance during its descent through theatmosphere. Every environment on Earth where there is liquid water sustains microbial life. For most of Earth’s history, theTo make best use of the rover’s science capabilities, a only life forms on this planet were microorganisms, ordiverse international team of scientists and engineers will microbes. Microbes still make up most of the living mat-make daily decisions about the rover’s activities for the ter on Earth. Scientists who specialize in the search forfollowing day. Even if all the rover’s technology performs life on other worlds expect that any life on Mars, if it hasflawlessly, some types of evidence the mission will seek existed at all, has been microbial.about past environments may not have persisted in therock record. While the possibility that life might have Curiosity will land in a region where this key item on theexisted on Mars provokes great interest, a finding that checklist of life’s requirements has already been deter-conditions did not favor life would also pay off with valu- mined: It was wet. Observations from Mars orbit duringable insight about differences and similarities between five years of assessing candidate landing sites haveearly Mars and early Earth. made these areas some of the most intensely studied places on Mars. Researchers have used NASA’s MarsHabitability Reconnaissance Orbiter to map the area’s mineralogy, finding exposures of clay minerals. Clays, other phyllosili-The mission will assess whether the area Curiosity ex- cates and sulfates form under conditions with adequateplores has ever been a potential habitat for Martian life. liquid water in a life-supporting, medium range between very acidic and very alkaline.Whether life has existed on Mars is an open questionthat this mission, by itself, is not designed to answer. Curiosity will inventory other basic ingredients for life,Curiosity does not carry experiments to detect active seek additional evidence about water and investigateprocesses that would signify present-day biological how conditions in the area have changed over time.metabolism, nor does it have the ability to image mi- The wet environment in which the clay minerals formedMars Science Laboratory Landing 8 Press Kit
  8. 8. is long gone, probably occurring more than 3 billion process would favor increased concentration of heavieryears ago. Examining the geological context for those isotopes in the retained, modern atmosphere. Suchminerals, such as the minerals in younger rock layers, processes can be relevant to habitability and biology.could advance understanding of habitat change to drier Curiosity will assess isotopic ratios in methane if thatconditions. The rover can also check for traces of water gas is in the air around the rover. Methane is an organicstill bound into the mineral structure of rocks at and near molecule, and its carbon isotope ratio can be verythe surface. distinctive. Observations from orbit and from Earth indi- cate traces of it may be present in Mars’ atmosphere.Carbon-containing compounds called organic mol- Isotopic ratios could hold clues about whether methaneecules are an important class of ingredients for life that is being produced by microbes or by a non-biologicalCuriosity can detect and inventory. This capability adds process.a trailblazing “follow the carbon” aspect to the MarsScience Laboratory, as part of the sequel to the “follow The mission has four primary science objectives tothe water” theme. meet NASA’s overall habitability assessment goal: • Assess the biological potential of at least one targetOrganic molecules contain one or more carbon atoms environment by determining the nature and inven-bound to hydrogen and, in many cases, additional ele- tory of organic carbon compounds, searching forments. They can exist without life, but life as we know the chemical building blocks of life and identifyingit cannot exist without them, so their presence would features that may record the actions of biologicallybe an important plus for habitability. If Curiosity detects relevant processes.complex organics that are important to life on Earth, • Characterize the geology of the rover’s field site atsuch as amino acids, these might be of biological origin, all appropriate spatial scales by investigating thebut also could come from non-biological sources, such chemical, isotopic and mineralogical composition ofas carbonaceous meteorites delivered to the surface of surface and near-surface materials and interpretingthe planet. the processes that have formed rocks and soils.Curiosity will also check for other chemical elements • Investigate planetary processes of relevance to pastimportant for life, such as nitrogen, phosphorus, sulfur habitability (including the role of water) by assessingand oxygen. the long-time-scale atmospheric evolution and de- termining the present state, distribution and cyclingThe rover will definitively identify minerals, which provide of water and carbon dioxide.a lasting record of the temperatures, pressures and • Characterize the broad spectrum of surface ra-chemistry present when the minerals were formed or diation, including galactic cosmic radiation, solaraltered. Researchers will add that information to obser- proton events and secondary neutrons.vations about geological context, such as the patternsand processes of sedimentary rock accumulation, to Preservation and Past Environmentschart a chronology of how the area’s environments havechanged over time. Energy for life on Mars could come Some of the same environmental conditions favorablefrom sunlight, heat or mixtures of chemicals (food) with for life can, paradoxically, be unfavorable for preserv-an energy gradient that could be exploited by biological ing evidence about life. Water, oxidants and heat, all ofmetabolism. The information Curiosity collects about which can contribute to habitability, can destroy organicminerals and about the area’s modern environment will molecules and other possible markers left by life, orbe analyzed for clues about possible past and present biosignatures.energy sources for life. Life has thrived on Earth for more than 3 billion years,Curiosity will measure the ratios of different isotopes of but only a miniscule fraction of Earth’s past life hasseveral elements. Isotopes are variants of the same ele- left evidence of itself in the rock record on this planet.ment with different atomic weights. Ratios such as the Preserving evidence of life from the distant past hasproportion of carbon-13 to carbon-12 can provide in- required specific, unusual conditions. On Earth, thesesight into planetary processes. For example, Mars once windows of preservation have included situations suchhad a much denser atmosphere than it does today, and as insects encased in amber and mastodons im-if the loss occurred at the top of the atmosphere, thatMars Science Laboratory Landing 9 Press Kit
  9. 9. mersed in tar pits. Mars won’t have fossils of insects or ing conditions over a range of times. Analyzing samplesmastodons; if Mars has had any life forms at all, they from different points in that range could identify which, ifwere likely microbes. Understanding what types of any, hold organics. The rover might find that the answerenvironments may have preserved evidence of microbial is none. While such an answer could shrink prospectslife from billions of years ago, even on Earth, is still an for finding evidence of ancient life on Mars, it wouldemerging field of study. strengthen the contrast between early Mars and early Earth. The history of environmental changes on anTo determine whether Mars ever supported life, a key Earth-like planet without life would be valuable for un-step is learning where biosignatures could persist. derstanding the history of life’s interaction with Earth’sCuriosity’s findings about windows of preservation will environment.serve this mission’s prospector role: identifying goodhunting grounds for possible future investigations about Modern EnvironmentMartian life’s existence and characteristics. They canalso guide this mission’s own course, informing deci- The Mars Science Laboratory will study the current envi-sions about where to drive and which rocks to sample ronment in its landing region as well as the records left byin Curiosity’s search for organics. past environments. Curiosity carries a weather station, an instrument for monitoring natural high-energy radiationAccumulation of rock-forming sediments writes a record and an instrument that can detect soil moisture and wa-of environmental conditions and processes into those ter-containing minerals in the ground beneath the rover.sedimentary rocks. The layers of the mountain inside The investigations of organics and other potential ingre-Gale Crater provide a record of events arranged in dients for life can analyze samples of modern-day soil forthe order in which they occurred. Researchers using what nutrients would be available to soil microbes. TheCuriosity can look at how environments changed over ability to check for methane in the atmosphere is a studytime, possibly including transitions from habitable condi- of modern processes, too. Methane would break downtions to non-habitable conditions. Some of the clues are and disappear from the atmosphere within a few centu-in the textures of the rocks, and Curiosity will be look- ries if not replenished by an active source, so its pres-ing for distinctive rock textures. Other clues are in the ence would be surprising.mineral and chemical compositions. Selection of Curiosity’s landing site was not based onSome conditions and processes, such as low tempera- traits favoring present-day habitability. However, much oftures and rapid entrapment in the sediments, can favor the information this mission contributes about the mod-preservation of organics and evidence about life. As ern environment will enhance our general understandingCuriosity looks for organics by analyzing samples drilled of Mars. For example, can organic compounds deliveredfrom sedimentary rocks, it will be reading the history of by meteorites persist in the soil close to the surface?past environments whether or not it finds organics. How does the modern atmosphere affect the ultraviolet and high-energy radiation that reaches the surface, pos-Some minerals and other geologic materials, such as ing a hazard to life and to preservation of organics? Howsulfates, phosphates, carbonates and silica, can help might we better estimate levels in the past? The rover’spreserve biosignatures. All of these materials, forming monitoring of radiation levels from cosmic rays and theunder just the right balance of environmental conditions, sun also is designed to address astronaut safety onhave the potential to preserve fragments of organic mol- eventual human missions to Mars.ecules derived from microbes or carbonaceous mete-orites. But not just any rock formed of suitable minerals Science Payloadwill do. Most on Earth do not. Expectations for Mars aresimilar, and the chances of a discovery — even if life had On April 14, 2004, NASA announced an opportunitybeen present — are very small. If this sounds sobering, for researchers to propose science investigations forit should be, but this is the only known way to prospect the Mars Science Laboratory mission. The solicitationfor the vestiges of life on the early Earth. for proposals said, “The overall science objective of the MSL mission is to explore and quantitatively assess aThe area at Gale Crater accessible to Curiosity as it potential habitat on Mars.” Eight months later, the agencydrives during the mission contains rocks and soils announced selection of eight investigations proposedthat may have been originally deposited under differ- competitively. In addition, Spain and Russia would eachMars Science Laboratory Landing 10 Press Kit
  10. 10. provide an investigation through international agree- complementary capabilities for showing the rover’s sur-ments. The instruments for these 10 investigations make roundings in exquisite detail and in motion.up the science payload on Curiosity. The right-eye Mastcam looks through a telephoto lens,The two instruments on the mast are a versatile, revealing details near or far with about three-fold betterhigh-definition imaging system, and a laser-equipped, resolution than any previous landscape-viewing cameraspectrum-reading camera that can hit a rock with a on the surface of Mars. The left-eye Mastcam provideslaser and observe the resulting spark for information broader context through a medium-angle lens. Eachabout what chemical elements are in the rock. The can acquire and store thousands of full-color images.tools on the turret at the end of Curiosity’s 7-foot-long Each is also capable of recording high-definition video.(2.1-meter-long) robotic arm include a radiation-emitting Combining information from the two eyes can yield 3-Dinstrument that reads X-ray clues to targets’ composi- views where the images overlap.tion and a magnifying-lens camera. The arm can deliversoil and powdered-rock samples to an instrument that Mastcam imaging of the shapes and colors of land-uses X-ray analysis to identify minerals in the sample scapes, rocks and soils will provide clues about the his-and to an instrument that uses three laboratory methods tory of environmental processes that have formed themfor assessing carbon compounds and other chemicals and modified them over time. Images and videos of theimportant to life and indicative of past and present pro- sky will document contemporary processes, such as thecesses. For characterizing the modern environment, the movement of clouds and dust.rover also carries instruments to monitor the weather,measure natural radiation and seek evidence of water The telephoto Mastcam is called “Mastcam 100” for itsbeneath the surface. To provide context for all the other 100-millimeter focal-length lens. Its images cover an areainstruments, a camera will record images of the landing about six degrees wide and five degrees tall, in 1,600 pix-area during descent. els by 1,200 pixels. This yields a scale of 2.9 inches (7.4 centimeters) per pixel at a distance of about six-tenths ofThe 10 science instruments on the Mars Science a mile (1 kilometer) and about 0.006 inch (150 microns)Laboratory have a combined mass of 165 pounds (75 per pixel at a distance of 6.6 feet (2 meters). The camerakilograms), compared with a five-instrument science provides enough resolution to distinguish a basketballpayload totaling 11 pounds (5 kilograms) on each of the from a football at a distance of seven football fields, or totwin rovers, Spirit and Opportunity, that landed on Mars read “ONE CENT” on a penny on the ground beside thein 2004. The mass of just one of Curiosity’s 10 instru- rover.ments, 88 pounds (40 kilograms) for Sample Analysis atMars, is nearly four times the 23-pound (10.6-kilogram) Its left-eye partner, called “Mastcam 34” for its 34-mil-total mass of the first Mars rover, 1997’s Sojourner on limeter lens, catches a scene three times wider — aboutthe Mars Pathfinder mission. 18 degrees wide and 15 degrees tall — on an identical detector. It can obtain images with 8.7 inches (22 cen-Assessing past and present habitability of environments timeters) per pixel at a distance of about six-tenths of aat sites visited by Curiosity will require integrating the mile (1 kilometer) and 0.018 inch (450 microns) per pixelresults of the various instruments, not any single instru- at a distance of 6.6 feet (2 meters).ment. Science operations and analysis will be coor-dinated through the Mars Science Laboratory Project The centers of Mastcam’s lenses sit about 6.5 feet (2.0Science Group, whose members are Project Scientist meters) above ground level. The eyes are farther apart —John Grotzinger, of the California Institute of Technology, about 10 inches (25 centimeters) — than the stereo eyesPasadena, Calif.; Program Scientist Michael Meyer of on earlier Mars surface robots. The cameras can focusNASA Headquarters, Washington; and the principal on features at any distance from about 6 feet (just underinvestigator for each of the following investigations. 2 meters) to infinity.Mast Camera (Mastcam) When Curiosity drives to a new location, the Mastcam 34 can record a full-color, full-circle panorama showing ev-Two two-megapixel color cameras on Curiosity’s mast erything from the nearby ground to the horizon by takingare the left and right eyes of the Mast Camera, or 150 images in about 25 minutes. For a first look, theseMastcam investigation. These versatile cameras have may be sent to Earth initially as compressed “thumbnail”Mars Science Laboratory Landing 11 Press Kit
  11. 11. versions. Mastcam thumbnail frames — roughly 150-by- include science spectral filters for examining the ground150-pixel versions of each image — can be sent as or sky in narrow bands of visible-light or near-infraredan index of the full-scale images held in the onboard wavelengths. These science filters can be used formemory. follow-up observations to gain more information about rocks or other features of interest identified in red-green-Using the Mastcam 100, the team will be able to see blue images. One additional filter on each camera allowsfarther off to the sides of the rover’s path, compared with it to look directly at the sun to measure the amount ofwhat has been possible with earlier Mars rovers. That dust in the atmosphere, a key part of Mars’ weather.will help with selection of the most interesting targets toapproach for analyzing with Curiosity’s other instruments Mastcam’s color-calibration target on the rover deckand will provide additional geological context for inter- includes magnets to keep the highly magnetic Martianpreting data about the chosen targets. dust from accumulating on portions of color chips and white-gray-balance reference chips. Natural lighting onThe Mastcams will provide still images and video to Mars tends to be redder than on Earth due to dust instudy motions of the rover — both for science, such Mars’ atmosphere. “True color” images can be pro-as seeing how soils interact with wheels, and for en- duced that incorporate that lighting effect — compa-gineering, such as aiding in use of the robotic arm. In rable to the warm, orange lighting that is experienced atother videos, the team may use cinematic techniques sunset on Earth. Alternatively, a white-balance calcula-such as panning across a scene and using the rover’s tion can be used to adjust for the tint of the lighting, asmovement for “dolly” shots. Video from the cameras is the human eye tends to do and digital cameras can do.720p high definition at four to seven frames per second, The Mastcams are capable of producing both true-colordepending on exposure time. and white-balanced images.Malin Space Science Systems, San Diego, built the The Mastcam principal investigator is Michael Malin, aMastcams and two of Curiosity’s other science instru- geologist who founded Malin Space Science Systemsments: the Mars Hand Lens Imager and the Mars and has participated in NASA Mars exploration since theDescent Imager. Mariner 9 mission in 1971–72.The four cameras from Malin Space Science Systems Chemistry and Camera (ChemCam)share several design features. They use a Bayer patternfilter, as found in many commercial digital cameras, for The investigation using a rock-zapping laser and a tele-color imaging. Bayer filtering means that the charge- scope mounted atop Curiosity’s mast is the Chemistrycoupled device (CCD) that detects each pixel of the and Camera suite, or ChemCam. It also includes spec-image is covered with a grid of green, red and blue filters trometers and electronics down inside the rover.so that the camera gets the three color componentsover the entire scene in a single exposure. This is a The laser can hit rock or soil targets up to about 23change from color cameras on earlier Mars landers and feet (7 meters) away with enough energy to excite arovers, which took a series of exposures through differ- pinhead-size spot into a glowing, ionized gas, calledent filters to be combined into color composites by pro- plasma. The instrument observes that spark with thecessing on Earth. The filter design used for Curiosity’s telescope and analyzes the spectrum of light to identifyscience cameras results in pictures in which the color the chemical elements in the target.closely mimics the way the average human eye sees theworld. Each of the cameras uses a focusing mechanism The telescope, with a diameter of 4.33 inches (110from MDA Information Systems Space Division, formerly millimeters), doubles as the optics for the camera ofAlliance Spacesystems, Pasadena, Calif. Each uses ChemCam, which records monochrome images ona Kodak CCD with an array of 1,600 by 1,200 active a 1,024-pixel-by-1,024-pixel detector. The telescopicpixels. Each has an eight-gigabyte flash memory. camera, called the remote micro-imager, or RMI, will show context of the spots hit with the laser. It can alsoBesides the affixed red-green-blue filter grid, the be used independently of the laser for observations ofMastcams have wheels of other color filters that can be targets at any distance.rotated into place between the lens and the CCD. TheseMars Science Laboratory Landing 12 Press Kit
  12. 12. Information from ChemCam will help researchers survey extreme environments, such as inside nuclear reactorsthe rover’s surroundings and choose which targets to and on the sea floor, and has had experimentalapproach for study with the tools on the arm and the applications in environmental monitoring and canceranalytical laboratory instruments. ChemCam can also detection, but ChemCam is its first use in interplanetaryanalyze many more targets than those instruments exploration.can. It can be used on multiple targets the same day,while the analytical laboratory investigations — SAM Roger Wiens, a geochemist with the U.S. Departmentand CheMin — take multiple days per target. It can also of Energy’s Los Alamos National Laboratory incheck the composition of targets inaccessible to the Los Alamos, N.M., is the principal investigator forrover’s other ingredient-identifying instruments, such as ChemCam. For developing, building and testing therock faces beyond the reach of Curiosity’s robotic arm. instrument, Los Alamos partnered with researchers in France funded by the French national space agency,The spot hit by ChemCam’s infrared laser gets more Centre National d’Études Spatiales. The deputy prin-than a million watts of power focused on it for five cipal investigator is Sylvestre Maurice, a spectroscopyone-billionths of a second. Light from the resulting flash expert with the Institut de Recherche en Astrophysiquecomes back to ChemCam through the telescope, then et Planétologie at the Observatoire Midi-Pyrénées,through about 20 feet (6 meters) of optical fiber down Toulouse, France.the mast to three spectrometers inside the rover. Thespectrometers record intensity at 6,144 different wave- France provided ChemCam’s laser and telescope. Thelengths of ultraviolet, visible and infrared light (wave- laser was built by Thales, Paris, France. Los Alamoslengths from 240 to 850 nanometers). Different chemical National Laboratory supplied the spectrometers andelements in the target, in their ionized state, emit light data processors. The optical design for the spectrome-at different wavelengths. Dozens of laser pulses on the ters came from Ocean Optics, Dunedin, Fla. NASA’s Jetsame spot will be used to achieve the desired accuracy Propulsion Laboratory, Pasadena, Calif., provided fiber-in identifying elements. Among the many elements that optic connections linking the two parts of the instru-the instrument can identify in rocks and soils are sodium, ment and a cooling machine to keep the spectrometersmagnesium, aluminum, silicon, calcium, potassium, cold. The ChemCam team includes experts in mineral-titanium, manganese, iron, hydrogen, oxygen, beryllium, ogy, geology, astrobiology and other fields, with somelithium, strontium, nitrogen and phosphorus. members also on other Curiosity instrument teams.If a rock has a coating of dust or a weathered rind, Alpha Particle X-Ray Spectrometer (APXS)hundreds of repeated pulses from the laser can removethose layers to provide a reading of the rock’s interior The Alpha Particle X-Ray Spectrometer (APXS) oncomposition and a comparison between the interior and Curiosity’s robotic arm, like its predecessors on thethe coating. arms of all previous Mars rovers, will identify chemical elements in rocks and soils.Researchers also plan to use ChemCam to study thesoil at each place Curiosity stops. These observations The APXS instruments on Sojourner, Spirit andwill document local and regional variations in the soil’s Opportunity produced important findings from thosecomposition and — from images taken through the missions, including salty compositions indicative of atelescope by the remote micro-imager — in the size wet past in bedrocks examined by Opportunity anddistribution of soil particles. the signature of an ancient hot spring or steam vent in soil examined by Spirit. The APXS on Curiosity deliv-Another capability will be to check for water, either ers greater sensitivity, better scheduling versatility and abound into mineral composition or as frost. By quickly new mode for optimal positioning.identifying hydrogen and oxygen, ChemCam can pro-vide unambiguous identification of water if any is on the The Canadian Space Agency contributed thissurface in the area Curiosity explores. Canadian-made instrument for the Mars Science Laboratory. A pinch of radioactive material emits radia-ChemCam uses a technology called laser-induced tion that “queries” the target and an X-ray detectorbreakdown spectroscopy. This method of determining “reads” the answer.the composition of an object has been used in otherMars Science Laboratory Landing 13 Press Kit
  13. 13. The APXS sensor head, about the size of a cupcake, Additional improvement in sensitivity, mainly for heavyrides on the multi-tool turret at the end of Curiosity’s arm. elements such as iron, comes from increasing theThe rover will place the spectrometer’s contact-sensing amount X-rays emitted by the curium. Curiosity’s APXSsurface directly onto most rock targets selected for has about 700 micrograms (in mass) or 60 millicuriesAPXS readings or just above some soil targets. (in radioactivity), which is twice as much as Spirit’s or Opportunity’s. Curium is a synthetic element first identi-The instrument determines the abundance of elements fied in a laboratory in 1944. The specific isotope used infrom sodium to strontium, including the major rock- all Mars rovers’ APXS instruments is curium 244, whichforming and soil-forming elements sodium, magnesium, has a half-life of 18.1 years. This makes it ideal for long-aluminum, silicon, calcium, iron and sulfur. In 10-minute duration missions, where even after more than sevenquick looks, it can detect even minor ingredients down years of the Opportunity mission, the loss in activity isto concentrations of about one-half percent. In three- hardly noticeable.hour readings, it can detect important trace elementsdown to concentrations of 100 or fewer parts per million. The additional X-ray intensity will benefit use of a tech-It has a high sensitivity to salt-forming elements such as nique called the scatter peak method, which wassulfur, chlorine and bromine, which can indicate interac- developed by physicist Iain Campbell, an APXS co-tion with water in the past. investigator at the University of Guelph, Ontario, Canada. This method extracts information about elements invis-The APXS will characterize the geological context and ible to X-rays, such as oxygen. It was used to detect andinform choices about acquiring samples for analysis in- quantify water bound in the minerals of salty subsurfaceside the mission’s analytical laboratory instruments: SAM soils examined by Spirit at Gusev Crater.and CheMin. Learning which elements, in what concen-trations, are in the targets will help researchers identify When the spectrometer is in contact with the target, itprocesses that formed the rocks and soils in the area of examines a patch about 0.7 inch (1.7 centimeters) inMars where Curiosity is working. diameter. It detects elements to a depth of about 0.0002 inch (5 microns) for low-atomic-weight elements and toThe spectrometer uses the radioactive element curium about 10 times that depth for heavier elements. The dustas a source to bombard the target with energetic alpha removal tool on Curiosity’s arm turret can be used toparticles (helium nuclei) and X-rays. This causes each el- brush some rock surfaces clean before APXS examinesement in the target to emit its own characteristic X-rays, them.which are then registered by an X-ray detector chipinside the sensor head. The investigation’s main elec- For some soil targets, to avoid pushing the instrumenttronics package, which resides inside the rover, records into the soil, the spectrometer will not be placed in directall detected X-rays with their energy and assembles the contact with the target. In those cases, placement willdetections into the X-ray spectrum of this sample. use a standoff distance of about 0.4 inch (1 centimeter) or less.On Spirit and Opportunity, the need for the X-ray detec-tor chip to stay cold, and the length of time necessary Another new feature for Curiosity’s APXS is an autono-for acquiring a measurement, have restricted most mous placement mode. With this software, as the armAPXS measurements to Martian nighttime hours. One moves the spectrometer step-by-step closer to the soil,change in Curiosity’s APXS is the possibility to activate a the instrument checks X-rays from the target for severalsolid-state electric cooler for the detector, for use of the seconds at each step. When the count rate reaches aAPXS during Martian daytime. predetermined criterion of what would be adequate for a good compositional reading, the software knows, “OK.Curiosity’s APXS can make measurements in about That’s close enough.” The arm’s approach movementsone-third the time needed for equivalent readings by its cease and the longer-duration APXS reading begins. Apredecessors. This improvement in sensitivity results more complex variation of this autonomous placementmainly from shrinking the distance between the X-ray mode may use brief readings at several positions paralleldetector and the sample by about one-third, to 0.75 to the ground surface, scanning a larger area for certaininch (19 millimeters). compositional criteria, such as ratio of iron to sulfur, and quickly selecting the most distinctive spots for longer- duration readings.Mars Science Laboratory Landing 14 Press Kit
  14. 14. Besides examining rocks and soils in place, the science lights and adjustable focus. Also, it sits on a longer arm,team can use the APXS to check processed samples one that can hold MAHLI up higher than the camerasthat the arm places on the rover’s observation tray and on the rover’s mast for seeing over an obstacle or cap-soil freshly exposed by action of the rover’s wheels. An turing a rover self-portrait.onboard basaltic rock slab, surrounded by nickel plate,will be used periodically to check the performance and When positioned at its closest range — about 0.8 inchcalibration of the instrument. (21 millimeters) from its target — the camera’s images have a resolution of slightly less than one one-thou-The principal investigator for Curiosity’s APXS is Ralf sandth of an inch (14 microns) per pixel. The field ofGellert, a physicist at the University of Guelph in Ontario, view for that close-up is a rectangle about 0.9 inch (2.2Canada. He was part of the team that designed and centimeters) by 0.7 inch (1.7 centimeters).built the Spirit and Opportunity APXS instruments atthe Max Planck Institute in Mainz, Germany, and pro- The camera can be held at a series of different dis-vided the new scientific design for the Mars Science tances from a target to show context as well as detailLaboratory APXS based on the experience gained by adjusting the focus. At about 3 feet (1 meter) fromthrough the long operation of those predecessors. MDA, a target, it still has a pixel resolution of about 0.02 inchin Brampton, Ontario, Canada, built the instrument as (half a millimeter) in a view covering an area about 2 feetthe prime contractor for the Canadian Space Agency. (70 centimeters) wide. By manipulation of arm position and focus, the camera can be used to examine hard-Mars Hand Lens Imager (MAHLI) ware on the rover or record time-lapse views of activi- ties such as opening a sample inlet cover.The Mars Hand Lens Imager, or MAHLI, is a focusablecolor camera on the tool-bearing turret at the end of MAHLI has two sets of white light-emitting diodes toCuriosity’s robotic arm. Researchers will use it for magni- enable imaging at night or in deep shadow. Two otherfied, close-up views of rocks and soils, and also for light-emitting diodes on the instrument glow at the ultra-wider scenes of the ground, the landscape or even the violet wavelength of 365 nanometers. These will make itrover. Essentially, it is a hand-held camera with a macro possible to check for materials that fluoresce under thislens and autofocus. illumination.The investigation takes its name from the type of hand Malin Space Science Systems, San Diego, developed,lens magnifying tool that every field geologist carries for built and operates MAHLI. This camera shares someseeing details in rocks. Color, crystal shapes, mineral traits with three other cameras on Curiosity from thecleavage planes and other visible details from such same company. It uses a red-green-blue filter grid likeclose-up observation provide clues to a rock’s composi- the one on commercial digital cameras for obtaining ation. In sedimentary rocks, the sizes and shapes of the full-color image with a single exposure. Its image detec-grains in the rock, and the scale of fine layering, provide tor is a charge-coupled device with an array of 1,600 byinformation about how the grains were transported 1,200 active pixels. It stores images in an eight-gigabyteand deposited. Sharp-edge grains have not been worn flash memory, and it can perform an onboard focusdown by tumbling long distances, for example. The size merge of eight images to reduce from eight to two theof grains can indicate whether the water or wind that number of images returned to Earth in downlink-limitedcarried them was moving quickly or not. situations.These clues garnered from MAHLI images can aid both Curiosity carries a vertically mounted calibration targetin selection of which targets to analyze with other instru- for MAHLI, for checking color, white balance, resolution,ments and in directly reading the environmental history focus and the ultraviolet illumination.recorded in the rocks and soils the rover encounters. Ken Edgett of Malin Space Science Systems, a ge-As a close-up magnifying camera, MAHLI resembles ologist who has helped run cameras on several Marsthe Microscopic Imager instrument mounted at the orbiters, is the principal investigator for MAHLI. A unifiedend of the robotic arm on each of the twin Mars rovers imaging-science team for the three Malin-supplied in-Spirit and Opportunity. MAHLI has significantly greater struments combines experience in geologic field work,capabilities than those predecessors, however: full color, Mars exploration and space cameras.Mars Science Laboratory Landing 15 Press Kit
  15. 15. Chemistry and Mineralogy (CheMin) the instrument. The other 27 are reusable holders for Martian samples.The Chemistry and Mineralogy experiment, or CheMin,is one of two investigations that will analyze powdered Each pair of cells is mounted on a metal holder that re-rock and soil samples delivered by Curiosity’s robotic sembles a tuning fork. A tiny piezoelectric buzzer excitesarm. It will identify and quantify the minerals in the the fork to keep the particles in the sample moving insidesamples. Minerals provide a durable record of past the cell during analysis of the sample. This puts the par-environmental conditions, including information about ticles in a random mix of orientations to the X-ray beam,possible ingredients and energy sources for life. improving detection of how the mineral crystals in the sample scatter the X-rays. The piezoelectric vibration,CheMin uses X-ray diffraction, a first for a mission to at about 200 cycles per second (middle C on a pianoMars. This is a more definitive method for identifying is 261 cycles per second) also helps keep the powderminerals than was possible with any instrument on previ- flowing during filling and dumping of the cell.ous missions. The investigation supplements the diffrac-tion measurements with X-ray fluorescence capability to CheMin generates X-rays by aiming high-energy elec-determine further details of composition by identifying trons at a target of cobalt. The X-rays emitted by theratios of specific elements present. cobalt are then directed into a narrow beam. During analysis, the sample sits between the incoming beamX-ray diffraction works by directing an X-ray beam at on one side and the instrument’s detector on the other.a sample and recording how X-rays are scattered by The detector is a charge-coupled device like the ones inthe sample at the atomic level. All minerals are crystal- electronic cameras, but sensitive to X-ray wavelengthsline, and in crystalline materials, atoms are arranged and cooled to minus 76 degrees Fahrenheit (minus 60in an orderly, periodic structure, causing the X-rays to degrees Celsius).be scattered at predictable angles. From those angles,researchers can deduce the spacing between planes Each CheMin analysis of a sample requires up toof atoms in the crystal. Each different mineral yields a 10 hours of accumulating data while the X-rays areknown, characteristic series of spacings and intensities, hitting the sample. The time may be split into two orits own fingerprint. more Martian nights of operation.On Curiosity’s deck, near the front of the rover, one fun- The X-ray diffraction data show the angles at which thenel with a removable cover leads through the deck top primary X-rays from the beam are deflected and theto the CheMin instrument inside the rover. The instru- intensity at each angle. The detector also reads second-ment is a cube about 10 inches (25 centimeters) on ary X-rays emitted by the sample itself when it is excitedeach side, weighing about 22 pounds (10 kilograms). by the primary X-rays. This is the X-ray fluorescence information. Different elements emit secondary X-rays atThe rover acquires rock samples with a percussive drill different frequencies. CheMin’s X-ray fluorescence capa-and soil samples with a scoop. A sample processing bility can detect elements with an atomic number greatertool on the robotic arm puts the powdered rock or soil than 11 (sodium) in the periodic table.through a sieve designed to remove any particles largerthan 0.006 inch (150 microns) before delivering the ma- Instruments that previous missions to Mars have usedterial into the CheMin inlet funnel. Vibration helps move for studying Martian minerals have not been able tothe sample material — now a gritty powder — down provide definitive identification of all types of minerals.the funnel. Each sample analysis will use about as much CheMin will be able to do so for minerals present inmaterial as in a baby aspirin. samples above minimal detection limits of about 3 per- cent of the sample composition. The instrument will alsoThe funnel delivers the sample into a disc-shaped cell, indicate the approximate concentrations of different min-about the diameter of a shirt button and thickness of a erals in the sample. X-ray fluorescence can add informa-business card. The walls of the sample cell are transpar- tion about the ratio of elements in types of minerals withent plastic. Thirty-two of these cells are mounted around variable elemental composition, such as the proportionthe perimeter of a sample wheel. Rotating the wheel can of iron to magnesium in iron magnesium silicate (olivine).position any cell into the instrument’s X-ray beam. Five It can also aid in identifying non-crystalline ingredients incells hold reference samples from Earth to help calibrate a sample, such as volcanic glass.Mars Science Laboratory Landing 16 Press Kit
  16. 16. Each type of mineral forms under a certain set of SAM’s analytical tools fit into a microwave-oven-size boxenvironmental conditions: the chemistry present (includ- inside the front end of the rover. While it is the biggesting water), the temperature and the pressure. Thus, of the 10 instruments on Curiosity, this tightly packedCheMin’s identification of minerals will provide informa- box holds instrumentation that would take up a goodtion about the environment at the time and place where portion of a laboratory room on Earth. One focus duringthe minerals in the rocks and soils formed or were al- development was power efficiency. For example, thetered. Some minerals the instrument might detect, such two ovens can heat powdered samples to about 1,800as phosphates, carbonates, sulfates and silica, can degrees Fahrenheit (1,000 degrees Celsius) drawing ahelp preserve biosignatures. Whether or not the mission maximum power of just 40 watts. More than a third of adetermines that the landing area has offered a favorable mile (more than 600 meters) of wiring is inside SAM.habitat for life, the inventory of minerals identified byCheMin will provide information about processes in the SAM can detect a fainter trace of organics and identifyevolution of the planet’s environment. a wider variety of them than any instrument yet sent to Mars. It also can provide information about other ingredi-David Blake, an expert in cosmochemistry and exobiol- ents of life and clues to past environments.ogy at NASA’s Ames Research Center, Moffett Field,Calif., is the principal investigator for CheMin. He began One of SAM’s tools, a mass spectrometer like thosework in 1989 on a compact X-ray diffraction instrument seen in many TV crime-solving laboratories, identifiesfor use in planetary missions. His work with colleagues gases by the molecular weight and electrical charge ofhas resulted in commercial portable instruments for use their ionized states. It will check for several elementsin geological field work on Earth, as well as the CheMin important for life as we know it, including nitrogen, phos-investigation. The spinoff instruments have found ap- phorous, sulfur, oxygen, hydrogen and carbon.plications in screening for counterfeit pharmaceuticals indeveloping nations and in analyzing archaeological finds. Another tool, a tunable laser spectrometer, uses absorp- tion of light at specific wavelengths to measure concen-NASA Ames Research Center won the 2010 Com- trations of methane, carbon dioxide and water vapor.mercial Invention of the Year Award from NASA for the It also identifies the proportions of different isotopes intuning-fork powder vibration system used on CheMin. those gases. Isotopes are variants of the same elementBlake and Philippe Sarazin of inXitu Inc., Campbell, with different atomic weights, such as carbon-13 andCalif., a co-investigator on the CheMin team, developed carbon-12, or oxygen-18 and oxygen-16. Ratios ofthe technology while Sarazin was working as a post- isotopes can be signatures of planetary processes,doctoral fellow at Ames. such as how Mars might have lost much of its former atmosphere.Sample Analysis at Mars (SAM) The suite’s third analytical tool, a gas chromatograph,The Sample Analysis at Mars investigation, or SAM, will separates different gases from a mixture to aid identifi-use a suite of three analytical tools inside Curiosity to cation. It detects organic compounds exiting a capillarystudy chemistry relevant to life. One key job is check- column, and then it feeds the separated fractions to theing for carbon-based compounds that on Earth are mass spectrometer for a more definitive identification.molecular building blocks of life. It will also examine thechemical state of other elements important for life, and SAM also includes a sample manipulation system, andit will assess ratios of different atomic weights of certain a chemical separation and processing laboratory to sup-elements for clues about planetary change and ongoing port the analytical tools. The sample manipulation sys-processes. tem maneuvers 74 sample cups, each about one-sixth of a teaspoon (0.78 cubic centimeter) in volume. TheSAM will examine gases from the Martian atmosphere chemical separation and processing laboratory includesand gases that ovens and solvents pull from powdered pumps, tubing, carrier-gas reservoirs, pressure monitors,rock and soil samples. Curiosity’s robotic arm will deliver ovens, temperature monitors and other components.the powdered samples to one of two inlet funnels on the Fifty-two specially designed microvalves direct the flow ofrover deck. Atmospheric samples enter through filtered gas through the system. Two soft-drink-can-size vacuuminlet ports on the side of the rover. pumps rotate 100,000 times per minute to allow all three instruments to operate at their optimal pressures.Mars Science Laboratory Landing 17 Press Kit
  17. 17. SAM’s analysis of material from Martian rocks or soils whether any organics close enough to the surface forbegins after powder collected and processed by tools Curiosity to reach them can persist in the harsh condi-on the arm is dropped into one of SAM’s two solid-sam- tions there without the carbon in them transforming intople inlets while the inlet’s protective cover is open. The a more polymerized state.inlet tubes are highly polished funnels that vibrate to getthe powder to fall into a reusable sample cup. NASA’s investigation of organics on Mars began with the twin Viking landers in 1976. The original reports fromFifty-nine of the instrument’s 74 cups are quartz that Viking came up negative for organics. SAM renews thecan be heated to very high temperatures. The sample search with three advantages.manipulation system pushes the quartz cup holdingthe powder into an oven that heats it to about 1,800 The first is Curiosity’s access. Mars is diverse, notdegrees Fahrenheit (about 1,000 degrees Celsius). That uniform. Copious information gained from Mars orbitersprocess releases gas from the sample at various tem- in recent years has enabled the choice of a landing siteperatures, depending on the chemistry of the sample. with favorable attributes, such as exposures of clay andThe mass spectrometer measures the release continu- sulfate minerals good at entrapping organic chemicals.ously. Some of the gas goes to the tunable laser spec- Mobility helps too, especially with the aid of high-resolu-trometer for measurement of isotopes. Some goes to tion geologic mapping generated from orbital observa-a trap that concentrates any organics, then to the gas tions. The stationary Viking landers could examine onlychromatograph and mass spectrometer. After use, the what their arms could reach. Curiosity can use mappedquartz cup can be baked to prepare it for re-use with geologic context as a guide in its mobile search foranother sample. organics and other clues about habitable environments. Additionally, SAM will be able to analyze samples fromSix of the cups hold calibration solids. SAM also carries more protected interiors of rocks drilled into by Curiosity,samples of gases for calibration. rather than being restricted to soil samples, as Viking was.Nine of the cups are for using a solvent method calledderivatization, rather than high temperature, to pull gases Second, SAM has improved sensitivity, with a capabilityfrom samples of Martian rocks and soils. If the mis- to detect organic compounds at parts per billion levelssion finds a site rich in organics, this method could be over a wider mass range of molecules and after heatingused to identify larger and more reactive organic mol- samples to a higher temperature.ecules than is possible with the high-heat method. Eachderivatization cup contains a mixture of a solvent and a Third, the derivatization method for assessing organ-chemical that, after it reacts with a compound of interest, ics in some SAM samples can reveal a wider range ofturns it into a more volatile compound that can be sepa- organic compounds than was possible with the Vikingrated in the gas chromatograph. These chemicals are experiment. In doing so, it can also check a recent hy-entirely sealed in with a foil cover. For analysis of sample pothesis that a reactive chemical recently discovered inpowder from a Martian rock or soil by this method, the Martian soil — perchlorate — may have masked organ-sample manipulation system punctures the foil and adds ics in soil samples baked during Viking tests.the powder to the liquid in the cup, and the oven heatsthe sample to a modest temperature to let the reactions If SAM does not detect any organics, that would beproceed rapidly. useful information about the unfavorable conditions for life near the Martian surface. Future missions might lookCuriosity’s “follow the carbon” investigation of organic deeper.compounds begins as a check for whether any are pres-ent. Although organic molecules are not, in themselves, If SAM does detect organics, one challenge will beevidence of life, life as we know it cannot exist without to confirm that these molecules are truly Martian, notthem. Their presence would be important evidence stowaways from Earth carried to Mars on Curiosity. Theboth about habitability and about the site’s capability for rover carries five encapsulated bricks of organic checkpreserving evidence of life. Meteorites bearing organic material to enable control experiments. The checkcompounds have pelted Mars, as well as Earth, for material is a silicon-dioxide ceramic laced with smallbillions of years. Uncertainty remains, however, about amounts of synthetic fluorinated organic chemicals notMars Science Laboratory Landing 18 Press Kit
  18. 18. found in nature on Earth and not expected on Mars. states and Europe to develop, build and test SAM afterThe basic control experiment will collect a powdered NASA selected his team’s proposal for it in 2004.sample from an organic check brick with the samedrilling, processing and delivery system used for collect- NASA Goddard Space Flight Center built and testeding samples from Martian rocks, and then will ana- SAM. France’s space agency, Centre National d’Étudeslyze the sample with SAM. If SAM finds any organics Spatiales, provided support to French researchers whoother than the fluorine-containing markers, they will be developed SAM’s gas chromatograph. NASA’s Jetstowaway suspects. If only the markers are detected, Propulsion Laboratory, Pasadena, Calif., provided thethat would verify that organic-detection is working and tunable laser spectrometer. Honeybee Robotics, Newthat the sample-acquisition and handling pathway has York, designed SAM’s sample manipulation system.passed a test of being clean of organic stowaways.That control experiment can assess characteristics of Rover Environmental Monitoring Station (REMS)organic contamination at five different times during themission, using the five bricks of organic check material. The Rover Environmental Monitoring Station, or REMS,Researchers have a variety of tools at their disposal to will record information about daily and seasonal chang-distinguish organic compounds present in Mars soils es in Martian weather.and rocks from trace levels of organic compounds fromEarth that might make their way into these samples. This investigation will assess wind speed, wind direction, air pressure, relative humidity, air temperature, groundIf organic chemicals are present in Martian samples, temperature and ultraviolet radiation. Operational plansSAM’s inventory of the types and mixtures may provide call for taking measurements for at least five minutesclues to their origin. For example, organics delivered every hour of the full-Martian-year (98-week) mission.by meteorites without involvement of biology comewith more random chemical structures than the pat- Spain provided this instrument for the Mars Scienceterns seen in mixtures of organic chemicals produced Laboratory.by organisms. Patterns, such as a predominance ofmolecules with an even number of carbon atoms, could Information about wind, temperatures and humiditybe suggestive of biological origin. The derivatization comes from electronic sensors on two finger-like boomsprocess also allows searching for specific classes of extending horizontally from partway up the main verticalorganics with known importance to life on Earth. For mast holding the ChemCam laser and the Mastcam.example, it can identify amino acids, the chain links of Each of the booms holds a sensor for recording air tem-proteins. While these clues may not add up to a defini- perature and three sensors for detecting air movementtive case either for or against biological origin, they could in three dimensions. Placement of the booms at anprovide important direction for future missions. angle of 120 degrees from each other enables calculat- ing the velocity even when the main mast is blocking theMethane is one of the simplest organic molecules. wind from one direction. The boom pointing toward theObservations from Mars orbit and from Earth in recent front of the rover, Boom 2, also holds the humidity sen-years have suggested transient methane in Mars’ atmo- sor inside a downward-tilted protective cylinder. Boomsphere, which would mean methane is being actively 1, pointing to the side and slightly toward the rear, holdsadded and then removed from the atmosphere of Mars. an infrared sensor for measuring ground temperature.With SAM’s tunable laser spectrometer, researchers willcheck to confirm whether methane is present, moni- The pressure sensor sits inside the rover body, con-tor any changes in its concentration, and look for clues nected to the external atmosphere by a tube to a small,about whether Mars methane is produced by biological dust-shielded opening on the deck. Electronics control-activity or by processes that do not require life. ling REMS are also inside the rover body.The principal investigator for SAM is Paul Mahaffy, The ultraviolet sensor is on the rover deck. It measuresa chemist at NASA’s Goddard Space Flight Center, six different wavelength bands in the ultraviolet por-Greenbelt, Md. He is a veteran of using spacecraft tion of the electromagnetic spectrum, including wave-instruments to study planetary atmospheres. Mahaffy lengths also monitored from above by NASA’s Marshas coordinated work of hundreds of people in several Reconnaissance Orbiter. No previous mission to theMars Science Laboratory Landing 19 Press Kit
  19. 19. surface of Mars has measured the full ultraviolet spec- The team plans to post daily weather reports fromtrum of radiation. Curiosity. Air temperature around the rover mast will likely drop to about minus 130 degrees FahrenheitThe REMS investigation will strengthen understanding (about minus 90 degrees Celsius) on some winter nightsabout the global atmosphere of Mars and contribute to and climb to about minus 22 Fahrenheit (about minusthe mission’s evaluation of habitability. 30 Celsius) during winter days. In warmer seasons, afternoon air temperature could reach a balmyThe data will provide a way to verify and improve atmo- 32 Fahrenheit (0 degrees Celsius).sphere modeling based mainly on observations fromMars orbiters. For example, significant fractions of the Radiation Assessment Detector (RAD)Martian atmosphere freeze onto the ground as a southpolar carbon-dioxide ice cap during southern winter and The Radiation Assessment Detector, or RAD, investi-as a north polar carbon-dioxide ice cap during northern gation on Curiosity monitors high-energy atomic andwinter, returning to the atmosphere in each hemisphere’s subatomic particles coming from the sun, from distantspring. At Curiosity’s landing site, far from either pole, supernovae and other sources. These particles consti-REMS will check whether seasonal patterns of changing tute naturally occurring radiation that could be harmfulair pressure fit the existing models for effects of the com- to any microbes near the surface of Mars or to astro-ing and going of polar carbon-dioxide ice. nauts on a future Mars mission.Monitoring ground temperature with the other weather RAD’s measurements will help fulfill the Mars Sciencedata could aid in assessment of whether conditions have Laboratory mission’s key goals of assessing whetherbeen favorable for microbial life. Even in the extremely Curiosity’s landing region has had conditions favor-low-humidity conditions anticipated in the landing area, able for life and for preserving evidence about life. Thisthe combination of ground temperature and humidity investigation also has an additional job. Unlike the restinformation could provide insight about the interaction of of the mission, RAD has a special task and funding fromwater vapor between the soil and the atmosphere. If the the part of NASA that is planning human explorationenvironment supports, or ever supported, any under- beyond Earth orbit. It will aid design of human missionsground microbes, that interaction could be crucial. by reducing uncertainty about how much shielding from radiation future astronauts will need. RAD is mak-Ultraviolet radiation can also affect habitability. The ul- ing measurements during the trip from Earth to Mars,traviolet measurements by REMS will allow scientists to supplementing those it will make during Curiosity’sbetter predict the amount of ultraviolet light that reaches roving on Mars, because radiation levels in interplan-Mars’ surface globally in the present and past. Ultraviolet etary space are also important in the design of humanlight is destructive to organic material and the reason missions.that sunscreen is worn on Earth. The 3.8-pound (1.7-kilogram) RAD instrument has aThe principal investigator for REMS is Javier Gómez- wide-angle telescope looking upward from the hard-Elvira, an aeronautical engineer with the Center for ware’s position inside the left-front area of the rover.Astrobiology (Centro de Astrobiología), Madrid, Spain. The telescope has detectors for charged particles withThe center is affiliated with the Spanish National masses up to that of an iron ion. RAD can also de-Research Council (Consejo Superior de Investigaciones tect neutrons and gamma rays coming from the MarsCientíficas) and the National Institute for Aerospace atmosphere above or the Mars surface material belowTechnology (Instituto Nacional de Técnica Aerospacial). the rover.Spain’s Ministry of Science and Innovation (Ministerio deCiencia e Innovación) and Spain’s Center for Industrial Galactic cosmic rays make up one type of radiation thatTechnology Development (Centro para el Desarrollo RAD monitors. These are a variable shower of chargedTecnológico Industrial) supplied REMS. The Finnish particles coming from supernova explosions and otherMeterological Insitute developed the pressure sensor. events extremely far from our solar system.To develop the instrument and prepare for analyzing The sun is the other main source of energetic particlesthe data it will provide, Spain has assembled a team of that this investigation detects and characterizes. Theabout 40 researchers — engineers and scientists. sun spews electrons, protons and heavier ions in “solarMars Science Laboratory Landing 20 Press Kit
  20. 20. particle events” fed by solar flares and ejections of mat- watch so that it can catch any rare but vitally importantter from the sun’s corona. Astronauts might need to solar particle events.move into havens with extra shielding on an interplan-etary spacecraft or on Mars during solar-particle events. The first science data from the mission have come from RAD’s measurements during the trip from Earth to Mars.Earth’s magnetic field and atmosphere provide effective These en-route measurements are enabling correlationsshielding against the possible deadly effects of galac- with instruments on other spacecraft that monitor solartic cosmic rays and solar particle events. Mars lacks particle events and galactic cosmic rays in Earth’s neigh-a global magnetic field and has only about 1 percent borhood and also are yielding data about the radiationas much atmosphere as Earth does. Just to find high- environment farther from Earth.enough radiation levels on Earth for checking and cali-brating RAD, the instrument team needed to put it inside RAD’s principal investigator is physicist Don Hasslermajor particle-accelerator research facilities in the United of the Southwest Research Institute’s Boulder, Colo.,States, Europe, Japan and South Africa. branch. His international team of co-investigators includes experts in instrument design, astronaut safety,The radiation environment at the surface of Mars has atmospheric science, geology and other fields.never been fully characterized. NASA’s Mars Odysseyorbiter, which reached Mars in 2001, assessed radiation Southwest Research Institute in Boulder and in Sanlevels above the Martian atmosphere with an investiga- Antonio, together with Christian Albrechts University intion named the Mars Radiation Environment Experiment. Kiel, Germany, built RAD with funding from the NASACurrent estimates of the radiation environment at the Exploration Systems Mission Directorate and Germany’ssurface rely on modeling of how the thin atmosphere national aerospace research center, Deutsches Zentrumaffects the energetic particles, but uncertainty in the für Luft- und Raumfahrt.modeling remains large. A single energetic particle hittingthe top of the atmosphere can break up into a cascade Measurements of ultraviolet radiation by Curiosity’sof lower-energy particles that might be more damaging Rover Environmental Monitoring Station will supplementthan a single high-energy particle. RAD’s measurements of other types of radiation.In addition to its precursor role for human exploration, Dynamic Albedo of Neutrons (DAN)RAD will contribute to the mission’s assessment ofMars’ habitability for microbes and search for organics. The Dynamic Albedo of Neutrons investigation, or DAN,Radiation levels probably make the surface of modern can detect water bound into shallow underground min-Mars inhospitable for microbial life and would con- erals along Curiosity’s path.tribute to the breakdown of any near-surface organiccompounds. The measurements from RAD will feed The DAN instrument shoots neutrons into the groundcalculations of how deeply a possible future robot on a and measures how they are scattered, giving it a highlife-detection mission might need to dig or drill to reach a sensitivity for finding any hydrogen to a depth of aboutmicrobial safe zone. For assessing whether the surface 20 inches (50 centimeters) directly beneath the rover.radiation environment could have been hospitable formicrobes in Mars’ distant past, researchers will combine The Russian Federal Space Agency contributed DANRAD’s measurements with estimates of how the activity to NASA as part of a broad collaboration between theof the sun and the atmosphere of Mars have changed in United States and Russia in the exploration of space.the past few billion years. The instrument can be used in reconnaissance to iden-Radiation levels in interplanetary space vary on many tify places for examination with Curiosity’s other tools.time scales, from much longer than a year to shorter Also, rock formations that Curiosity’s cameras view atthan an hour. Assessing the modern radiation environ- the surface may be traced underground by DAN, ex-ment on the surface will not come from a one-time set of tending scientists’ understanding of the geology.measurements. Operational planning for Curiosity antici-pates that RAD will record measurements for 15 minutes DAN will bring to the surface of Mars an enhancementof every hour throughout the prime mission, on steady of nuclear technology that has already detected MartianMars Science Laboratory Landing 21 Press Kit

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