Image: Artist's concept of NASA's Curiosity rover
NASA/JPL-Caltech
An artist's concept of NASA's Curiosity rover searching for samples on the Martian surface.
By
updated 10/23/2012 6:32:37 PM ET 2012-10-23T22:32:37

There’s growing buzz about data gleaned by NASA’s Curiosity rover on Mars, specifically over the issue of methane detection on the Red Planet.

On one hand, methane can be geological in origin. But then there’s the prospect that the gas is biotic, or caused by living organisms — meaning it could be the gaseous residue of long-extinct microbes or even the output of Martian organisms alive and well today.

Curiosity is toting the Sample Analysis at Mars instrument suite, or SAM, an onboard lab that accounts for more than half of the science payload on the 1-ton rover. Though SAM's components would ordinarily fill a laboratory here on Earth, they have been miniaturized to roughly the size of a microwave oven in order to fit inside the robot.

SAM's duty is to analyze gases that are either "sniffed" directly from the Martian atmosphere (which it has done several times) or extracted from soil or powdered rock samples by heating or chemically treating the samples.

Provided by NASA’s Goddard Space Flight Center, SAM is on the search for compounds of the element carbon, including methane, that are associated with life. SAM will also explore ways in which those compounds are generated and destroyed in the Martian ecosphere. [Mars Methane: Could It Mean Life? (Video)]

According to Goddard's SAM website, determining the presence or absence of organic molecule would yield important science results. Either presence or absence would provide important information about the environmental conditions of Gale Crater, where Curiosity touched down on Aug. 5.

If SAM does find organic material, the next step would be to determine the origin and the nature of preservation of the molecules.

But if SAM does not find organic material, a better place to look might be below the surface.

Key question
"The key question about methane on Mars is not its presence, but its variability," said Chris McKay, space scientist and Mars specialist at NASA's Ames Research Center in Mountain View, Calif. As shown by many engaged in the methane-on-Mars issue, it is known that organics are falling onto the surface of Mars and that ultraviolet light produces methane from them, he told Space.com.

"So there will certainly be methane at some level, possibly well below one part per billion," McKay said.

  1. Space news from NBCNews.com
    1. KARE
      Teen's space mission fueled by social media

      Science editor Alan Boyle's blog: "Astronaut Abby" is at the controls of a social-media machine that is launching the 15-year-old from Minnesota to Kazakhstan this month for the liftoff of the International Space Station's next crew.

    2. Buzz Aldrin's vision for journey to Mars
    3. Giant black hole may be cooking up meals
    4. Watch a 'ring of fire' solar eclipse online

"But what was surprising in the Mars Express results and the Earth-based observations was the variability," he added, referring to the European Space Agency's Mars Express orbiter. "Methane on Mars should have a lifetime of 300 years and should not be variable. If it is variable, this is very hard to explain with present theory. It requires unexpected sources and unexpected sinks."

In terms of Curiosity’s SAM instrument, McKay said that the key will be the tracking of whatever methane is seen over time.

"If it’s constant, then this can be reconciled with normal processes and a meteoritic source of organics. If it’s highly variable, then all bets are off." [5 Bold Claims of Alien Life]

Waiting to exhale
"Methane should be there," said astrobiologist Dirk Schulze-Makuch of Washington State University in Pullman. One of his research interests focuses on the interaction of microbes with their natural geological environment in an aqueous medium.

Schulze-Makuch says his view is based on three independent earlier studies, with methane usually associated with biological activity or ancient biology activity.

"Methane is really quite a rare gas in hydrothermal/volcanic exhalations; thus a methane detection with the rover would be exciting and could point to biology, especially if detected in relatively large amounts," Schulze-Makuch told Space.com.

"Even more exciting," Schulze-Makuch said, "would be if the carbon in the methane has an isotopic fractionation that is consistent with biology. If the methane is produced by organisms — for example, metabolism — then we expect a shift to the lighter isotopes. In essence because life is lazy, same effect, with less work compared to inorganically produced carbon."

Whether any Mars methane detections would be sufficiently high to determine the isotope ratio, Schulze-Makuch said, is a wait-and-see moment. "But it would be very exciting. To try and determine the isotopic fractionation and a good inorganic baseline for carbon would be the next step in my view." [7 Biggest Mysteries of Mars]

Modeling research
Malynda Chizek, an astronomy graduate student at New Mexico State University, recently outlined her research results on mapping the simulated methane distribution during different seasons on Mars. She presented her findings during last week’s American Astronomical Society’s Division for Planetary Sciences meeting in Reno, Nev.

Chizek told Space.com that she too is eager to see the Curiosity results announced.

Chizek is working on computer simulations using the NASA/Ames Mars Atmospheric General Circulation Model to replicate trace gases in the Martian atmosphere. Her modeling research enables the tracing back of detected methane to its source location to see whether it is coming from something like a volcanic source, water surface chemistry interaction or bacteria living on or near the surface.

Counting cows
Chizek said that there have been several claims of methane detection in the past decade, from Mars-orbiting spacecraft as well as telescopic observations from Earth. But those claims tend to be controversial, she said, because observations suggest that it’s varying in abundance on a very quick time scale, which is unexpected.

Detecting methane on Mars could lead to evidence of life, as roughly 95 percent of the methane in Earth’s atmosphere is a product of biology, Chizek said. In her recent talk at the DPS meeting, she underscored the volume and significance of methane on Mars by using a very Earthly creature that produces the gas: cows.

So how many cows would be required to equal the amount of methane that scientists have observed on Mars? "Depending on which observations I am looking at, that number is close to 5 million cows, or roughly 200,000 tons of methane production per year," Chizek reported.

What next?
Whatever methane news the Curiosity rover uncovers, more work is ahead, Chizek said.

"In order to constrain the Martian methane origin, I would need to know about the variation in methane measurements by Curiosity over time. So, I would want the rover to take many more measurements, which I assume is the plan if they do detect methane," Chizek said.

Chizek said that if there is only about a plus/minus 10 percent variation over time, then it might suggest that the methane is leftover from some unknown event in the past.

"If the methane abundance variation has a definite seasonal variation, then it might suggest some sort of biological origin, although there are also some geological mechanisms which might respond to seasonal change," Chizek said. "If there is a random, sporadic change in methane abundance, then I think it would likely be a geological production or release mechanism."

Chizek added that the latter two also require an as-yet unknown mechanism for methane destruction or removal, while the 10 percent variation is what would be expected, shored up by current knowledge of long-lived, non-condensing gases in the Martian atmosphere.

"Mars is thought to be a geologically dead planet," Chizek said in a statement released by New Mexico State University. "If the methane detections are confirmed, and we do not find any signs of bacterial life, this means there are likely some interesting geological processes happening on Mars that we don’t yet know about."

Leonard David has been reporting on the space industry for more than five decades. He is a winner of last year's National Space Club Press Award and a past editor-in-chief of the National Space Society's Ad Astra and Space World magazines. He has written for Space.com since 1999.

© 2013 Space.com. All rights reserved. More from Space.com.

Photos: Curiosity's space odyssey to Mars

loading photos...
  1. Caring for Curiosity

    NASA's Curiosity rover is as big as a compact car and weighs a ton ... and it's on Mars. Here's where the journey began. A white-room team works on the six-wheeled spacecraft on Aug. 13, 2011, at the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center in Florida. (NASA via Getty Images) Back to slideshow navigation
  2. Liftoff!

    An Atlas 5 rocket rises from Cape Canaveral Air Force Station in Florida on Nov. 26, 2011, with NASA's Mars Science Laboratory spacecraft sealed inside its payload fairing. That spacecraft, in turn, enclosed and protected the Curiosity rover. (NASA via Getty Images) Back to slideshow navigation
  3. Mohawk Guy at work

    Activity lead Bobak Ferdowsi works inside the Spaceflight Operations Facility for NASA's Curiosity rover at NASA's Jet Propulsion Laboratory in Pasadena, Calif., on Aug. 5, 2012 - the rover's landing day. Ferdowsi, who adopts a fresh hairdo for each space mission, became an Internet sensation thanks to his stars-and-stripes Mohawk and his youthful manner. (Brian van der Brug / Pool via Getty Images) Back to slideshow navigation
  4. Curious about Curiosity

    Jasper Goldberg and Andreas Bastian, both 22, watch live NASA coverage of Curiosity's descent to Mars on the giant video screen in New York's Times Square. (Andrew Burton / Reuters) Back to slideshow navigation
  5. Watching and waiting

    Steve Collins waits for word at the Jet Propulsion Laboratory's mission control room during the "seven minutes of terror" as Curiosity approaches the surface of Mars on Aug. 5. Collins was working at JPL in 1993 when NASA's Mars Observer probe was lost just before its scheduled arrival at the Red Planet. (Fred Prouser / Reuters) Back to slideshow navigation
  6. Touchdown!

    The Mars Science Laboratory team in the Mission Support Area at NASA's Jet Propulsion Laboratory reacts after learning that the Curiosity rover has landed safely on Mars. The happy news came at 10:31 p.m. PT Aug. 5 (1:31 a.m. ET Aug. 6). (Bill Ingalls / NASA via Reuters) Back to slideshow navigation
  7. From Mars to Times Square

    Spectators in New York's Times Square cheer the announcement that NASA's Curiosity rover successfully landed on Mars. (Peter Foley / EPA) Back to slideshow navigation
  8. Great catch!

    As it flew high above, NASA's Mars Reconnaissance Orbiter captured this picture of the Curiosity rover and its parachute descending to the Martian surface on Aug. 5. The inset image has been processed to bring out additional detail in the view of the rover and the chute. (NASA / JPL-Caltech via AP) Back to slideshow navigation
  9. Flying saucer

    A color image shows the Mars Science Laboratory's heat shield, as seen by a camera on the Curiosity rover during the spacecraft's descent on Aug. 5. The picture was obtained by the Mars Descent Imager instrument, also known as MARDI, and shows the 15-foot (4.5-meter) diameter heat shield when it was flying away 50 feet (16 meters) below the spacecraft. This image shows the inside surface of the heat shield, with its protective multilayered insulation. (NASA / JPL-Caltech / MSSS) Back to slideshow navigation
  10. The mountain ahead

    One of the first views from NASA's Curiosity rover, which landed on Mars on Aug. 5, shows the rover's shadow in the foreground and a 3-mile-high mountain known as Aeolis Mons or Mount Sharp in the distance. That mountain is the rover's eventual destination. The picture was taken through a "fisheye" wide-angle lens by one of the rover's hazard avoidance cameras. (NASA / JPL-Caltech via AFP - Getty) Back to slideshow navigation
  11. Miles and miles on Mars

    This image, released on Aug. 9, shows part of the deck of NASA's Curiosity rover as seen by one of the rover's navigation cameras. The rover's pointy low-gain antenna and its paddle-shaped high-gain antenna are among the pieces of hardware visible in the foreground. The rim of Gale Crater can be seen at the horizon. (NASA / JPL-Caltech via AFP - Getty) Back to slideshow navigation
  12. Curiosity's crime scene

    The four main pieces of hardware that arrived on Mars with NASA's Curiosity rover are pinpointed in this image from NASA's Mars Reconnaissance Orbiter, taken 24 hours after landing. The heat shield was the first piece to hit the ground, followed by the back shell attached to the parachute. The rover itself was lowered to the ground on cables by its rocket-powered sky crane. The cables were cut, and then the sky crane flew away to its own crash landing. (NASA / JPL-Caltech via Getty Images) Back to slideshow navigation
  13. What a blast!

    This is a portion of the first 360-degree black-and-white panoramic view acquired by the navigation cameras aboard NASA's Curiosity rover. Two disturbed areas are visible in the foreground, where the rocket thrusters on Curiosity's sky crane blasted away the surface gravel to reveal bedrock below. The high country of Gale Crater's rim can be seen in the distance. (NASA / JPL-Caltech via AFP - Getty) Back to slideshow navigation
  14. First color picture

    An image from the Curiosity rover's Mars Hand Lens Imager, or MAHLI, provides the first color view of the north wall and rim of Gale Crater. The picture was taken by the MAHLI camera at the end of Curiosity's stowed robotic arm. The view appears fuzzy because of the dust that has settled on the camera's removable cover. (NASA / JPL-Caltech / MSSS via AP) Back to slideshow navigation
  15. Mars in living color

    A color image from NASA's Curiosity Rover shows the pebble-covered surface of Mars. This is a portion of the first color 360-degree panorama from NASA's Curiosity rover, made up of thumbnails, which are small copies of higher-resolution images. The mission's destination, a mountain at the center of Gale Crater called Aeolis Mons or Mount Sharp, can be seen in the distance rising up toward the left. Blast marks from the rover's descent stage are in the foreground. (NASA / JPL-Caltech / MSSS / Getty Images) Back to slideshow navigation
  16. Pew-pew

    This composite image, with magnified insets, shows the results of the first laser test by the ChemCam instrument aboard NASA's Curiosity rover on Mars. The composite incorporates a Navcam image taken prior to the test, with insets taken by the camera in ChemCam. The circular insert highlights the rock before the laser test. The square inset is further magnified and processed to show the effect of the laser blasts on Aug. 19. (LANL / MSSS / JPL-Caltech / NASA via Reuters) Back to slideshow navigation
  17. Looking ahead

    The Mars Curiosity rover's robotic arm takes aim at Mount Sharp in a mosaic that combines navigation-camera imagery from Sols 2, 12 and 14 (Aug. 8, 18 and 20). Mount Sharp, also known as Aeolis Mons, is a 3-mile-high mountain within Gale Crater that will be the rover's ultimate destination. (Marco Di Lorenzo / Ken Kremer / JPL-Caltech / NASA) Back to slideshow navigation
  18. Future mapped out

    NASA's Curiosity rover landed inside Gale Crater at the green dot, within the Yellowknife quadrangle, on Aug. 5. The team has decided to send it first to the region marked by a blue dot, that is nicknamed Glenelg. That area marks the intersection of three kinds of terrain. Then the rover will aim for the blue spot marked "Base of Mt. Sharp," where a natural break in Martian sand dunes will provide an opening for Curiosity to begin scaling the lower reaches of Mount Sharp. (Univ. of Ariz. / JPL-Caltech / NASA via Reuters) Back to slideshow navigation
  19. First steps

    Curiosity's navigation camera system looks back at the wheel tracks from the rover's first test drive on Aug. 22. The $2.5 billion rover made its first moves a little more than two weeks after its arrival on Mars. (JPL-Caltech / NASA via AFP - Getty Images) Back to slideshow navigation
  20. Mount Sharp

    Mount Sharp is seen in the distance in an image taken Aug. 23 by the 34-millimeter Mast Camera on Curiosity. The gravelly area around Curiosity's landing site is visible in the foreground. Farther away, about a third of the way up from the bottom of the image, the terrain falls off into a depression (a swale). Beyond the swale, in the middle of the image, is the boulder-strewn, red-brown rim of a moderately-sized impact crater. Father off in the distance, there are dark dunes and then the layered rock at the base of Mount Sharp. Some haze obscures the view, but the top ridge, depicted in this image, is 10 miles (16.2 kilometers) away. Scientists enhanced the color to show the Martian scene under the lighting conditions we have on Earth. (NASA via AFP - Getty Images) Back to slideshow navigation
  21. Hip-hop on Mars

    Will.i.am of the Black Eyed Peas sings at NASA's Jet Propulsion Laboratory on Aug. 28. Will.i.am's "Reach for the Stars" officially became the first song broadcast from Mars, thanks to a signal beamed from Curiosity. (Nick Ut / AP) Back to slideshow navigation
  22. Mmm, Marsberries!

    Small spherical objects fill the field in this Martian mosaic combining four images from the Microscopic Imager on NASA's Opportunity rover. The Sept. 6 view covers an area about 2.4 inches (6 centimeters) across, at an outcrop called Kirkwood in the Cape York segment of the western rim of Mars' Endeavour Crater. Shortly after its landing in 2004, Opportunity spotted similar spherules that were nicknamed "blueberries," but these berries are not as rich in iron, posing a scientific puzzle. (NASA/JPL-Caltech/Cornell Univ./ USGS/Modesto Junior College via EPA) Back to slideshow navigation
  23. 'Do I look fat?' Curiosity checks its belly

    A mosaic of photos taken on Sept. 9 by the Mars Hand Lens Imager on NASA's Curiosity rover shows the underside of the rover and its six wheels, with Martian terrain stretching back to the horizon. The four circular features on the front edge of the rover are the lenses for the left and right sets of Curiosity's hazard avoidance cameras, or Hazcams. Because of the different perspectives used for different images, some of the borders of the photos don't line up precisely. (NASA via AFP - Getty Images) Back to slideshow navigation
  24. A Martian rock called Jake

    NASA's Curiosity rover stopped about 8 feet (2.5 meters) in front of this Red Planet rock on Sept. 19, the mission's 43rd Martian day, or sol. The pyramid-shaped chunk was the first rock that the Curiosity rover touched for science's sake. It was named "Jake Matijevic" in honor of a top engineer who worked on every one of NASA's rover missions — but passed away just days after Curiosity's landing. Jake the rock, which measures about 10 inches (25 centimeters) tall, provided a good reference point for the rover's sophisticated instruments. (NASA via Getty Images) Back to slideshow navigation
  25. Rover's footprint

    NASA's Curiosity rover cut a wheel scuff mark into a wind-formed ripple at the "Rocknest" site on Mars to give researchers a better opportunity to examine the particle-size distribution of the material forming the ripple. The rover's right navigation camera took this image of the scuff mark on the mission's 57th Martian day, or sol (Oct. 3), the same sol that a wheel created the mark. For scale, the width of the wheel track is about 16 inches (40 centimeters). (Handout / Reuters) Back to slideshow navigation
  26. Rover's self-portrait

    The Curiosity rover used the Mars Hand Lens Imager (MAHLI) to capture the set of thumbnail images stitched together to create this full-color self-portrait in this Oct. 31, 2012 image from NASA. (NASA via Reuters) Back to slideshow navigation
  27. Life on Mars?

    The first sample of powdered rock extracted by the drill of Curiosity is seen on Feb. 20, 2013. Powder drilled out of a rock on Mars contains the best evidence yet that the Red Planet could have supported living microbes billions of years ago, the team behind NASA's Curiosity rover said March 12, 2013.

    Curiosity rover sees life-friendly conditions in ancient Mars rock. (NASA/JPL/Caltech/MSSS via EPA) Back to slideshow navigation
  28. The big picture

    This picture isn't from the Curiosity rover - it's a 2003 image from the Hubble Space Telescope, showing the full disk of Mars. The big picture hints at how much we'll be learning about the Red Planet during Curiosity's two-year, $2.5 billion mission. And that's just the beginning: Scientists hope the nuclear-powered rover will last years or even decades longer. (NASA via AP) Back to slideshow navigation
  1. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  2. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  3. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  4. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  1. Image: NASA's Jet Propulsion Lab Holds Viewing Of Mars Curiosity Rover Landing
    NASA via Getty Images
    Above: Slideshow (28) Curiosity's space odyssey to Mars
  2. AURA / STSCI / NASA
    Slideshow (24) The greatest hits from Mars
  3. Image:
    Y. Beletsky / ESO
    Slideshow (12) Month in Space: January 2014

Explainer: 11 amazing things the Mars rover can do

  • The car-sized Curiosity rover is a 1-ton robotic beast that will take planetary exploration to the next level.

    Curiosity rover is the centerpiece of NASA's $2.5 billion Mars Science Laboratory. Its main goal is to assess whether the Red Planet is, or ever was, capable of supporting microbial life. The rover will employ 10 different science instruments to help it answer this question once it touches down on the Red Planet. Here's a brief rundown of these instruments (and one more on the rover's heat shield).

    — Mike Wall, Space.com

  • Mast Camera (MastCam)

    T.A. Dutch Slager / NASA / JPL-Caltech
    This view of the Curiosity rover's remote sensing mast shows the ChemCam in the white box at top, and the two cameras of the Mastcam system just below. Additional navigation cameras are placed farther outward from the Mastcam cameras.

    The MastCam is Curiosity's workhorse imaging tool. It will capture high-resolution color pictures and video of the Martian landscape, which scientists will study and laypeople will gawk at.

    MastCam consists of two camera systems mounted on a mast that rises above Curiosity's main body, so the instrument will have a good view of the Red Planet environment as the rover chugs through it. MastCam images will also help the mission team drive and operate Curiosity. (Photos of NASA's Curiosity Rover)

  • Mars Hand Lens Imager (MAHLI)

    NASA / JPL-Caltech
    The Curiosity rover's Mars Hand Lens Imager will acquire color close-up images of rocks and surface materials. A Swiss Army knife is shown for scale.

    MAHLI will function much like a high-powered magnifying glass, allowing Earthbound scientists to get up-close looks at Martian rocks and soil. The instrument will take color pictures of features as tiny as 12.5 microns — smaller than the width of a human hair.

    MAHLI sits on the end of Curiosity's five-jointed, 7-foot (2.1-meter) robotic arm, which is itself a marvel of engineering. So mission scientists will be able to point their high-tech hand lens pretty much wherever they want.

  • Mars Descent Imager (MARDI)

    NASA / JPL-Caltech / MSSS
    The Mars Descent Imager is flying on the Curiosity rover. A Swiss Army knife is included in the picture for purposes of showing scale.

    MARDI, a small camera located on Curiosity's main body, will record video of the rover's descent to the Martian surface (which will be accomplished with the help of a hovering, rocket-powered sky crane). (Video: Curiosity's Peculiar Landing)

    MARDI will click on a mile or two above the ground, as soon as Curiosity jettisons its heat shield. The instrument will then take video at five frames per second until the rover touches down. The footage will help the MSL team plan Curiosity's Red Planet rovings, and it should also provide information about the geological context of the landing site, the 100-mile-wide (160-km) Gale Crater.

  • Sample Analysis at Mars (SAM)

    NASA / JPL-Caltech
    This illustration of the mechanical configuration of the SAM shows the three instruments and several elements of the Chemical Separation and Processing Laboratory.

    SAM is the heart of Curiosity; at 83 pounds (38 kilograms), it makes up about half of the rover's science payload.

    SAM is actually a suite of three separate instruments — a mass spectrometer, a gas chromatograph and a laser spectrometer. These instruments will search for carbon-containing compounds, the building blocks of life as we know it. They will also look for other elements associated with life on Earth, such as hydrogen, oxygen and nitrogen.

    The SAM instrument suite is located in Curiosity's main body. The rover's robotic arm will drop samples into SAM via an inlet on the rover's exterior. Some of these samples will come from the interior of rocks, powder bored out by a 2-inch (5-centimeter) drill situated at the end of the arm.

    None of Curiosity's predecessors could get deep into Martian rocks, so scientists are excited about the drill.

    "For a geologist that studies rocks, there's nothing better than getting inside," said MSL deputy project scientist Joy Crisp, of NASA's Jet Propulsion Laboratory in Pasadena, Calif.

  • Chemistry and Mineralogy (CheMin)

    NASA / JPL-Caltech
    Clean-room workers carefully steer the hoisted CheMin instrument toward its installation into the Curiosity rover.

    CheMin will identify different types of minerals on Mars and quantify their abundance, which will help scientists better understand past environmental conditions on the Red Planet.

    Like SAM, CheMin has an inlet on Curiosity's exterior to accept samples delivered by the rover's robotic arm. The instrument will shine a fine X-ray beam through the sample, identifying minerals' crystalline structures based on how the X-rays diffract.

    "This is like magic to us," Crisp told Space.com. X-ray diffraction is a leading diagnostic technique for Earthbound geologists, she explained, but it hasn't made it to Mars yet. So CheMin should help Curiosity provide more definitive mineral characterizations than previous Mars rovers such as Spirit and Opportunity have been able to achieve.

  • Chemistry and Camera (ChemCam)

    NASA / JPL-Caltech
    An artist's conception shows the Curiosity rover's ChemCam firing its laser at Martian rock.

    For sheer coolness, it's tough to beat ChemCam. This instrument will fire a laser at Martian rocks from up to 30 feet (9 meters) away and analyze the composition of the vaporized bits.

    ChemCam will thus enable Curiosity to study rocks that are out of reach of its flexible robotic arm. It will also help the mission team determine from afar whether or not they want to send the rover over to investigate a particular landform.

    ChemCam is composed of several different parts. The laser sits on Curiosity's mast, along with a camera and a small telescope. Three spectrographs sit in the rover's body, connected to the mast components by fiber optics. The spectrographs will analyze the light emitted by excited electrons in the vaporized rock samples.

  • Alpha Particle X-Ray Spectrometer (APXS)

    NASA / JPL-Caltech
    The sensor head for the Alpha Particle X-ray Spectrometer is installed during testing. The head is 7.8 centimeters or about 3 inches tall.

    APXS, which sits at the end of Curiosity's arm, will measure the abundances of various chemical elements in Martian rocks and dirt.

    Curiosity will place the instrument in contact with samples of interest, and APXS will shoot out X-rays and helium nuclei. This barrage will knock electrons in the sample out of their orbits, causing a release of X-rays. Scientists will be able to identify elements based on the characteristic energies of these emitted X-rays.

    Spirit and Opportunity were outfitted with a previous version of APXS and used the instrument to help elucidate the prominent role water has played in shaping the Martian landscape. (Latest Mars Photos From Spirit and Opportunity)

  • Dynamic Albedo of Neutrons (DAN)

    NASA / JPL-Caltech / Roscosmos
    This diagram shows how the Detector of Albedo Neutrons could be used to sense the presence of subsurface water on Mars.

    DAN, located near the back of Curiosity's main body, will help the rover search for ice and water-logged minerals beneath the Martian surface.

    The instrument will fire beams of neutrons at the ground, then note the speed at which these particles travel when they bounce back. Hydrogen atoms tend to slow neutrons down, so an abundance of sluggish neutrons would signal underground water or ice.

    DAN should be able to map out water concentrations as low as 0.1 percent at depths up to 6 feet (2 m).

  • Radiation Assessment Detector (RAD)

    NASA / JPL-Caltech
    The RAD instrument is mounted just below the Curiosity rover's top deck, with the charged particle telescope pointing toward the zenith.

    The toaster-size RAD is designed specifically to help prepare for future human exploration of Mars. The instrument will measure and identify high-energy radiation of all types on the Red Planet, from fast-moving protons to gamma rays.

    RAD's observations will allow scientists to determine just how much radiation an astronaut would be exposed to on Mars. This information could also help researchers understand how much of a hurdle Mars' radiation environment might have posed to the origin and evolution of life on the Red Planet.

  • Rover Environmental Monitoring Station (REMS)

    NASA
    This diagram shows the location of the REMS booms on the rover's mast, plus detailed views showing the location of wind, humidity and temperature sensors.

    This tool, which sits partway up Curiosity's mast, is a Martian weather station. REMS will measure atmospheric pressure, humidity, wind speed and direction, air temperature, ground temperature and ultraviolet radiation.

    All of this information will be integrated into daily and seasonal reports, allowing scientists to get a detailed look at the Martian environment.

  • MSL Entry, Descent and Landing Instrumentation (MEDLI)

    Lockheed Martin
    The MEDLI instrument package is the black box in the middle left of this photo, which shows the heatshield for the Mars Science Laboratory.

    MEDLI isn't one of Curiosity's 10 instruments, since it was built into the heat shield that protected the rover during its descent through the Martian atmosphere. But it's worth a few words here.

    MEDLI measured the temperatures and pressures that the heat shield experienced as the MSL spacecraft streaked through the Martian sky. This information can tell engineers how well the heat shield, and their models of the spacecraft's trajectory, performed.

    Researchers will use MEDLI data to improve designs for future Mars-bound spacecraft.

    You can follow Space.com senior writer Mike Wall on Twitter: @michaeldwall. Follow Space.com for the latest in space science and exploration news on Twitter @Spacedotcom and on Facebook.

  • More from Space.com:

Discuss:

Discussion comments

,

Most active discussions

  1. votes comments
  2. votes comments
  3. votes comments
  4. votes comments