Catalog Page for PIA05468

Find a Node - Use these links to navigate to any of the 8 publicly accessible PDS Nodes.

This bar indicates that you are within the PDS enterprise which includes 6 science discipline nodes and 2 support nodes which are overseen by the Project Management Office at NASA's Goddard Space Flight Center (GSFC). Each node is led by an expert in the subject discipline, supported by an advisory group of other practitioners of that discipline, and subject to selection and approval under a regular NASA Research Announcement.

PIA05468: "McKittrick" Rich in Sulfur

These plots, or spectra, show that a rock dubbed 'McKittrick' near the Mars Exploration Rover Opportunity's landing site at Meridiani Planum, Mars, possesses the highest concentration of sulfur yet observed on Mars.

Target Name:	Mars
Is a satellite of:	Sol (our sun)
Mission:	Mars Exploration Rover (MER)
Spacecraft:	Opportunity
Instrument:	Alpha Particle X-ray Spectrometer Rock Abrasion Tool (RAT)
Product Size:	1920 x 1080 pixels (w x h)
Produced By:	JPL
Full-Res TIFF:	PIA05468.tif (546.9 kB)
Full-Res JPEG:	PIA05468.jpg (137.5 kB)

Click on the image above to download a moderately sized image in JPEG format (possibly reduced in size from original)

Original Caption Released with Image:

These plots, or spectra, show that a rock dubbed "McKittrick" near the Mars Exploration Rover Opportunity's landing site at Meridiani Planum, Mars, possesses the highest concentration of sulfur yet observed on Mars. These data were acquired with the rover's alpha particle X-ray spectrometer, which produces a spectrum, or fingerprint, of chemicals in martian rocks and soil. This instrument contains a radioisotope, curium-244, that bombards a designated area with alpha particles and X-rays, causing a cascade of reflective fluorescent X-rays. The energies of these fluorescent X-rays are unique to each atom in the periodic table, allowing scientists to determine a target's elemental composition.

The spectra shown here are taken from "McKittrick" and a soil patch nicknamed "Tarmac," both of which are located within the small crater where Opportunity landed. "McKittrick" measurements were acquired after the rover drilled a hole in the rock with its rock abrasion tool. Only portions of the targets' full spectra are displayed. The data are expressed as X-ray intensity (linear scale) versus energy. The measured area is 28 millimeters (1 inch) in diameter.

When comparing two spectra, the relative intensities at a given energy are proportional to the elemental concentrations, however these proportionality factors can be complex. To be precise, scientists extensively calibrate the instrument using well-analyzed geochemical standards.

Both the alpha particle X-ray spectrometer and the rock abrasion tool are located on the rover's instrument deployment device, or arm.

Image Credit:

NASA/JPL/Cornell/Max Planck Institute

Image Addition Date:

2004-03-02