Sample Analysis at Mars (SAM) Instrument Suite

SAM is a suite of instruments used in MSL. It is an international collaboration with components from NASA GSFC, JPL, the University of Paris, and Honeybee Robotics. There are five primary goals of this toolkit, distributed over three separate quests.

1. Carbon Quest - Goals:
   
   1. Identify carbon compounds, their sources, and their transformational processes.
   2. Detect molecules relevant to terrestrial life.


2. Water Quest - Goals:
   
   1. Determine spatial distribution and chemical states of key light elements and analyze the volatiles released from minerals that trace aqueous and geological processes.


3. Isotopes and Oxidants Quest - Goals:
   
   1. Examine oxidation chemistry and impact on organic molecules.
   2. Quantify isotopic signatures of planetary evolution.

Planned SAM Configuration

SAM will operate over the entire MSL surface mission. A set of pre-programmed analysis sequences available on SAM can be executed with a simple set of commands. SAM is also highly flexible and can respond to new discoveries with online re-programming. Consumables such as GC carrier are sufficient for more than 80 separate analyses over the nominal mission. A large subset of SAM science operations will continue after consumables are exhausted.

A fully capable SAM testbed facility will operate at NASA Goddard during MSL surface operations. Analog samples and sequences will be tested prior to execution on Mars. The SAM Science Team will participate, remotely and on-site, in MSL sequence definition.

The SAM GCMS is provided by the technical team that designed and fabricated the Cassini/Huygens GCMS, the first such instrument to be selected by NASA since the Viking Lander experiments more than 3 decades ago. Numerous elements of the Huygens GCMS are used in SAM. The TLS has a rich flight heritage including miniature instruments developed for Mars.

Sample Flow in SAM

Instruments

1. Quadrupole Mass Spectrometer (QMS)

QMS analyzes the atmosphere, gases thermally-evolved from solid samples, with or without preprocessing in the CSPL. QMS is the primary detector for GC.

2. Gas Chromatograph (GC)

GC separates complex mixtures into molecular components for QMS and GC stand alone analysis.

3. Tunable Laser Spectrometer (TLS)

Precise isotope ratios and abundances in targeted species:
H2O, CH4, CO, CO2, OCS, H2O2, and N2O.

Subsystems

1. Chemical Separation and Processing Laboratory (CSPL)

The CSPL uses reliable separation methods to extract compounds from solid samples and transform them into gases for GCMS and TLS analysis. The CSPL separates and enriches gases to maximize detection sensitivity and isotopic precision.

2. Sample Manipulation System (SMS)

The SMS receives ground sample from the MSL Sample Processing and Distribution System and delivers them to sealed vacuum ports for EGA.

3. Wide Range Pumps (WRP)
High-throughput WRPs evacuate the QMS and LDMS, as well as process gas for GCMS. WRPs and high-conductance valves enable static and dynamic QMS.