This image graphs four gases released ("evolved") when powdered rock from the target rock "Cumberland" was heated inside the Sample Analysis at Mars (SAM) instrument suite on NASA's Curiosity Mars rover. The data come from the second Cumberland sample analyzed by SAM. The released gases were detected by SAM's quadrupole mass spectrometer.
The graphic shows four gases (oxygen, hydrochloric acid, carbon dioxide, and nitric oxide) evolved.
The mass spectrometer signal for each gas is scaled separately so that the same graph can illustrate the temperatures that caused the gas to be released (for example, nitric oxide, NO, has been scaled up 25 times). These evolved gases and the temperatures at which they evolved suggest the presence of oxychlorine compounds, such as perchlorates, and of carbon- and nitrogen-bearing components in the rock-powder sample.
The Cumberland target rock is in the "Yellowknife Bay" area of Mars' Gale Crater.
NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Mars Science Laboratory Project and the mission's Curiosity rover for NASA's Science Mission Directorate in Washington. The rover was designed and assembled at JPL, a division of the California Institute of Technology in Pasadena.
More information about Curiosity is online at http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl/.