Forum für Wissenschaft, Industrie und Wirtschaft

Hauptsponsoren:     3M 
Datenbankrecherche:

 

Curiosity Shakes, Bakes, and Tastes Mars with SAM

04.12.2012
NASA's Curiosity rover analyzed its first solid sample of Mars in Nov. with a variety of instruments, including the Sample Analysis at Mars (SAM) instrument suite.

Developed at NASA's Goddard Space Flight Center in Greenbelt, Md., SAM is a portable chemistry lab tucked inside the Curiosity rover. SAM examines the chemistry of samples it ingests, checking particularly for chemistry relevant to whether an environment can support or could have supported life.


This artist's concept features NASA's Mars Science Laboratory Curiosity rover, a mobile robot for investigating Mars' past or present ability to sustain microbial life. Credit: NASA/JPL-Caltech

The sample of Martian soil came from the patch of windblown material called "Rocknest," which had provided a sample previously for mineralogical analysis by Curiosity's Chemistry and Mineralogy (CheMin) instrument. CheMin also received a new sample from the same Rocknest scoop that fed SAM. SAM has previously analyzed samples of the Martian atmosphere.

SAM can get a solid sample of Mars from either a drill or a scoop attached to the end of Curiosity's robotic arm. Since Rocknest is essentially a pile of loose soil, the scoop was used this time.

"This is the first time we've analyzed a solid sample using all three instruments that comprise SAM," said Paul Mahaffy, SAM Principal Investigator at NASA Goddard. "We also cleaned Curiosity's sample manipulation system and successfully tested our ability to move the sample from the manipulation system through the instrument suite."

A complex choreography was required to get the sample inside SAM for analysis, according to Mahaffy. First, since the scoop might still have had contamination from Earth, the first three scoops were shaken, run through a sieve, then dumped right back on the surface with the idea that they would carry away any contaminants with them. A sieved portion of the fourth scoop – just a few thousandths of a gram – was then delivered to SAM. A cover that protects SAM from accidentally ingesting windblown material was opened, and Curiosity's arm positioned the sample over SAM's inlet funnels. Before the sample was dropped, SAM turned on its inlet funnel vibrators, which move the sample into a tiny quartz cup. After the sample dropped, the vibrator was turned off, the cover was closed, and the cup, which is on a carousel holding 74 sample cups, was lowered and moved to one of two ovens.

After the sample was baked to release its gases, SAM's three instruments "digested" them and gave Curiosity its first "taste" of Mars. A basic three-step process will be used to analyze future samples as well:

Separate the molecules:
Gas from the sample first travels to the Gas Chromatograph (GC) instrument. The purpose of this instrument is to sort out all the different molecules in the sample, and tell how much of each kind there is. It accomplishes this by using a stream of helium gas to push the sample down a long, narrow tube (which is wound into a coil to save space). Helium is used because it is inert, meaning it won't react with and change any of the sample molecules. The inside of the tube is coated with a thin film. As molecules travel through the tube, they stick for a bit on the film, and the heavier the molecule, the longer it sticks. Thus, the lighter molecules emerge from the tube first, followed by the middleweight molecules, with the heaviest molecules bringing up the rear.

Identify the molecules:

Since molecules of different weights emerge from the tube of the gas chromatograph at different times, the GC can send groups of different weights, one at a time, to SAM's next instrument, which will determine exactly what kind of molecule makes up each of the groups. This is the Quadrupole Mass Spectrometer (QMS) instrument. It fires high-speed electrons at the molecules, breaking them up into fragments and giving the molecules and their fragments an electric charge. These molecules and their fragments with an electric charge can be moved by electric fields. The QMS uses both direct current and alternating current fields to sort the electrically charged molecules and fragments based on their weight (mass). Molecules and fragments of different mass are counted by a detector at different times to generate a mass spectrum, which is a pattern that uniquely identifies molecules.

Identify the volatiles and determine the isotopes:

After the QMS identifies the molecules, the sample is directed into the Tunable Laser Spectrometer (TLS), which can identify and analyze certain volatile molecules, like methane and carbon dioxide. The sample enters a chamber with precisely positioned mirrors at both ends. A laser is fired through a tiny hole in one of the mirrors. As the laser light bounces between the mirrors, it illuminates the sample. Different molecules will absorb certain colors (frequencies) of light, so the TLS identifies the molecules by which colors of the laser are blocked (since the laser is tunable, it can be adjusted to shine in a range of colors).

The TLS can also identify isotopes the same way. Isotopes are versions of an element that are a little bit heavier because their nucleus contains more neutrons. For example, carbon 13 is an atom of carbon with an extra neutron, so it is a heavier version of the more common carbon 12. Occasionally, a carbon 13 will take the place of a carbon 12 in an organic molecule. This is important since life prefers to use the lighter isotopes, because chemical reactions with them require less energy. So if we measure the isotopes of carbon in a material and discover that there is more light carbon relative to heavy carbon than would be found randomly, we might guess that we are seeing the effects of life.

Finally, since volatile molecules are found in the atmosphere as well as in soil and rock, samples of the Martian air can be sent directly to the TLS without going through SAM's other instruments.

SAM was developed at NASA Goddard, but with significant elements provided by industry, university, and NASA partners. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Curiosity/Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington. JPL designed and built the rover.

For more information about SAM, refer to the "SAM I am" site at: http://ssed.gsfc.nasa.gov/sam/samiam.html

For more information about the Curiosity rover, visit: http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl Nancy Neal-Jones / Bill Steigerwald
NASA's Goddard Space Flight Center, Greenbelt, Md.
Nancy.N.Jones@nasa.gov / William.A.Steigerwald@nasa.gov
Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
Guy.webster@jpl.nasa.gov

Bill Steigerwald | EurekAlert!
Further information:
http://www.nasa.gov
http://www.nasa.gov/mission_pages/msl/news/sam-tastes-mars.html

More articles from Physics and Astronomy:

nachricht Astronomers find unexpected, dust-obscured star formation in distant galaxy
24.03.2017 | University of Massachusetts at Amherst

nachricht Gravitational wave kicks monster black hole out of galactic core
24.03.2017 | NASA/Goddard Space Flight Center

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Wegweisende Erkenntnisse für die Biomedizin: NAD⁺ hilft bei Reparatur geschädigter Erbinformationen

Eine internationale Forschergruppe mit dem Bayreuther Biochemiker Prof. Dr. Clemens Steegborn präsentiert in 'Science' neue, für die Biomedizin wegweisende Forschungsergebnisse zur Rolle des Moleküls NAD⁺ bei der Korrektur von Schäden am Erbgut.

Die Zellen von Menschen und Tieren können Schäden an der DNA, dem Träger der Erbinformation, bis zu einem gewissen Umfang selbst reparieren. Diese Fähigkeit...

Im Focus: Designer-Proteine falten DNA

Florian Praetorius und Prof. Hendrik Dietz von der Technischen Universität München (TUM) haben eine neue Methode entwickelt, mit deren Hilfe sie definierte Hybrid-Strukturen aus DNA und Proteinen aufbauen können. Die Methode eröffnet Möglichkeiten für die zellbiologische Grundlagenforschung und für die Anwendung in Medizin und Biotechnologie.

Desoxyribonukleinsäure – besser bekannt unter der englischen Abkürzung DNA – ist die Trägerin unserer Erbinformation. Für Prof. Hendrik Dietz und Florian...

Im Focus: Fliegende Intensivstationen: Ultraschallgeräte in Rettungshubschraubern können Leben retten

Etwa 21 Millionen Menschen treffen jährlich in deutschen Notaufnahmen ein. Im Kampf zwischen Leben und Tod zählt für diese Patienten jede Minute. Wenn sie schon kurz nach dem Unfall zielgerichtet behandelt werden können, verbessern sich ihre Überlebenschancen erheblich. Damit Notfallmediziner in solchen Fällen schnell die richtige Diagnose stellen können, kommen in den Rettungshubschraubern der DRF Luftrettung und zunehmend auch in Notarzteinsatzfahrzeugen mobile Ultraschallgeräte zum Einsatz. Experten der Deutschen Gesellschaft für Ultraschall in der Medizin e.V. (DEGUM) schulen die Notärzte und Rettungsassistenten.

Mit mobilen Ultraschallgeräten können Notärzte beispielsweise innere Blutungen direkt am Unfallort identifizieren und sie bei Bedarf auch für Untersuchungen im...

Im Focus: Gigantische Magnetfelder im Universum

Astronomen aus Bonn und Tautenburg in Thüringen beobachteten mit dem 100-m-Radioteleskop Effelsberg Galaxienhaufen, das sind Ansammlungen von Sternsystemen, heißem Gas und geladenen Teilchen. An den Rändern dieser Galaxienhaufen fanden sie außergewöhnlich geordnete Magnetfelder, die sich über viele Millionen Lichtjahre erstrecken. Sie stellen die größten bekannten Magnetfelder im Universum dar.

Die Ergebnisse werden am 22. März in der Fachzeitschrift „Astronomy & Astrophysics“ veröffentlicht.

Galaxienhaufen sind die größten gravitativ gebundenen Strukturen im Universum, mit einer Ausdehnung von etwa zehn Millionen Lichtjahren. Im Vergleich dazu ist...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Alle Focus-News des Innovations-reports >>>

Anzeige

Anzeige

IHR
JOB & KARRIERE
SERVICE
im innovations-report
in Kooperation mit academics
Veranstaltungen

Rund 500 Fachleute aus Wissenschaft und Wirtschaft diskutierten über technologische Zukunftsthemen

24.03.2017 | Veranstaltungen

Lebenswichtige Lebensmittelchemie

23.03.2017 | Veranstaltungen

Die „Panama Papers“ aus Programmierersicht

22.03.2017 | Veranstaltungen

 
VideoLinks
B2B-VideoLinks
Weitere VideoLinks >>>
Aktuelle Beiträge

Rund 500 Fachleute aus Wissenschaft und Wirtschaft diskutierten über technologische Zukunftsthemen

24.03.2017 | Veranstaltungsnachrichten

Förderung des Instituts für Lasertechnik und Messtechnik in Ulm mit rund 1,63 Millionen Euro

24.03.2017 | Förderungen Preise

TU-Bauingenieure koordinieren EU-Projekt zu Recycling-Beton von über sieben Millionen Euro

24.03.2017 | Förderungen Preise