12.13.2016 Now and Long Ago at Gale Crater, Mars
12.13.2016 Where's Boron? Mars Rover Detects It
10.03.2016 Curiosity Self-Portrait at 'Murray Buttes'
10.03.2016 Butte 'M9a' in 'Murray Buttes' on Mars
09.19.2016 Ribbon Cutting
09.09.2016 Farewell to Murray Buttes (Image 5)
09.09.2016 Farewell to Murray Buttes (Image 4)
09.09.2016 Farewell to Murray Buttes (Image 3)
09.09.2016 Farewell to Murray Buttes (Image 2)
09.09.2016 Farewell to Murray Buttes (Image 1)
08.26.2016 Out-of-this-World Records
03.30.2016 Erisa Hines
03.30.2016 Buzz Aldrin
02.12.2016 Women in Science
02.09.2016 Adam Steltzner, a JPL engineer
01.27.2016 Night Close-up of Martian Sand Grains
01.27.2016 Curiosity Self-Portrait at Martian Sand Dune
12.17.2015 Alteration Effects at Gale and Gusev Craters
12.17.2015 Full-Circle View Near 'Marias Pass' on Mars
12.11.2015 Surface Close-up of a Martian Sand Dune
12.11.2015 Martian Sand Disturbed by Rover Wheel
11.24.2015 Carbon Exchange and Loss Processes on Mars
11.17.2015 Chemical Laptop 1
Indication of Hydration in Veins and Nodules of 'Knorr' in 'Yellowknife Bay'At different locations on the surface of the same rock, scientists can use the Mast Camera (Mastcam) on NASA's Mars rover Curiosity to measure the amount of reflected light at a series of different wavelengths. This yields spectral information that can be an indicator of composition.
The inset photograph in the lower center of this graphic shows two locations on a rock target called "Knorr," where Mastcam spectral measurements were made: A light-toned vein and part of the host rock. Knorr is in the "Yellowknife Bay" area of Gale Crater, close to Curiosity's "John Klein" rock drilling site.
The main graph shows the spectra recorded at those two points, with increasing wavelengths of visible light and near-infrared light from left to right, and with increasing intensity of reflectance from bottom to top. The bright vein shows greater reflectance through the range of wavelengths assessed. The shapes of the two curves also differ, especially where the vein spectrum dips in the near-infrared wavelengths. The range of wavelengths included in box-outlined portion of the vein spectrum is shown at the top of the group of reference spectra to the right. These reference spectra show how the dip in reflectance at those wavelengths in the vein material corresponds to dips in those wavelengths in several types of hydrated minerals -- minerals that have molecules of water bound into their crystalline structure, including hydrated calcium-sulfates. Mastcam is not sensitive to all hydrated minerals, however, including many phyllosilicates.
The reference spectra are from the U.S. Geological Survey's Spectral Library and the University of Winnipeg Planetary Spectrophotometer Facility.
Image Credit: NASA/JPL-Caltech/MSSS/ASU