Planning for NASA's 2020 Mars rover envisions a basic structure that capitalizes on re-using the design and engineering work done for the NASA rover Curiosity, which landed on Mars in 2012, but with new science instruments selected through competition for accomplishing different science objectives with the 2020 mission.
Seeking signs of past life on Mars would be a multi-step process, according to the Science Definition Team for NASA's Mars 2020 mission. The process would begin with using the 2020 rover's instruments to assess whether past conditions were favorable for microbial life and for preserving evidence about Martian life, if it existed. The next step would be searching for possible evidence of any past life, or "potential biosignatures." This search could be done both on Mars, with instruments on the rover, and using laboratories on Earth to examine selected Martian samples returned to Earth. The Mars 2020 rover would collect and package selected samples for possible return to Earth by a future mission. Return of Martian samples for analysis in laboratories on Earth would also enable the next step: recognizing a definitive sign of past Martian life -- a "definitive biosignature."
This shows one prototype for hardware to cache samples of cores drilled from Martian rocks for possible future return to Earth. A major objective for NASA's Mars 2020 rover, as described by the Mars 2020 Science Definition Team, would be to collect and package a carefully selected set of up to 31 samples in a cache that could be returned to Earth by a later mission. The capabilities of laboratories on Earth for detailed examination of cores drilled from Martian rocks would far exceed the capabilities of any set of instruments that could feasibly be flown to Mars. The exact hardware design for the 2020 mission is yet to be determined. For scale, the diameter of the core sample shown in the image is 0.4 inch (1 centimeter).
NASA/JPL-Caltech/LANL/CNES/IRAP/LPGNantes/CNRS/LGLyon/Planet-Terre, M. Fries
These two images illustrate the value of being able to identify different compositions at very small scales. At left, a mosaic of images from the remote micro-imager of the Chemistry and Camera (ChemCam) instrument on NASA's Mars rover Curiosity covers a scene about 3.5 inches (about 9 centimeters) across. ChemCam's ability to zap a target with a laser and analyze the resulting spark identified different compositions in the matrix rock and the lighter-toned veins. The image at right covers an area about three one-thousandths of one inch (about 75 microns) across in a meteorite from Mars examined on Earth. At this much finer scale, too, the veins have different composition from the matrix around them, as determined using Raman spectroscopy. The color-coding for composition is red for jarosite, green for goethite and blue for clay minerals. NASA's Mars 2020 rover, as described by the Mars 2020 Science Definition Team, would have capabilities for nested-scale observations and localized composition identification down to microscopic scale.
Observations at large scales, such as panoramas of Martian landscapes, help researchers identify smaller-scale features of special interest for examination in more detail. This concept of nested scales is illustrated here with images from the right Mast Camera (Mastcam) on NASA's Mars rover Curiosity that show the lower stratigraphy at "Yellowknife Bay" inside Gale Crater on Mars. The location of the right-side image within the left-side image is indicated by the white box. The white box in the right image indicates a smaller feature of interest that requires even higher spatial resolution. NASA's Mars 2020 rover, as described by the Mars 2020 Science Definition Team, would have capabilities for nested-scale observations down to microscopic scale.
The next rover to Mars should search for signs of past microbial life and collect a cache of rocks that a later mission could bring back to Earth, a NASA-appointed panel said Tuesday.
The recommended science goals are the most ambitious yet for any Mars mission.
Scientists have long wanted to examine Martian rocks and dirt under a microscope on Earth, but spacecraft sent to the surface so far don't have the capability to store samples.
Though the 2020 rover should be designed to collect rocks, the panel said NASA isn't obligated to bring them back.
NASA has the final say on what the future rover will accomplish.
The space agency said last year said it planned to launch another spacecraft to the red planet in 2020 following the success of Curiosity, which touched down in Gale Crater to much fanfare.
To keep costs down, engineers will recycle spare parts where possible and use the same landing technology that delivered the car-size Curiosity to the surface.
Curiosity recently departed on a monthslong trek toward a mountain rising from the middle of the crater.
The team's report, posted online Tuesday, describes recommended science goals for the mission slated to launch in 2020.