I'm sitting in on a NASA Jet propulsion laboratory teleconference for science journalists, with an update for the world on the Mars Curiosity rover's mission. Curiosity completes her "checkout" phase today. Including an "intermission" of 13 sols, and one remaining sol to inspect the rover's robotic arm, 26 sols have been devoted to so-called checkout duties. Today is sol 37. Rover is currently facing a Southeast direction. Temperatures on the rover are between 7 and 33 C. She has covered a little over a football field's distance on the surface of Mars. Ability to move the arm has been confirmed, and the ability of the rover to perform sampling is confirmed.
Curiosity has so far driven 109 meters from its original landing site, and engineers are driving her about 40 meters per sol. The first drilling into the surface of Mars is expected to occur about a month from now, following various surface activities (scraping rock surfaces, and so on).
Three speakers in the teleconference: Jennifer Trosper, JPL; Curiosity mission manager. Ralf Gellert, University of Guelph, in Guelph, Ontario, Canada; principal investigator for the Alpha Particle X-Ray Spectrometer instrument (or APXS) on Curiosity. Ken Edgett, Malin Space Science Systems, San Diego; principal investigator for the Mars Hand Lens Imager (or MAHLI) on Curiosity.
At the top of this blog post, the first Mars image of the day (larger size here):
Opening and Closing SAM. This set of images from NASA's Curiosity rover shows the inlet covers for the Sample Analysis at Mars instrument opening and closing, as the rover continues to check out its instruments in the first phase after landing. These images were taken by the Navigation camera on the 36th Martian day, or sol, of the rover's operations on Mars (Sept. 11, 2012). The rover's mast is casting a shadow over the deck. (NASA/JPL-Caltech)
Above, the Alpha Particle X-Ray Spectrometer (APXS) on NASA's Curiosity rover, with the Martian landscape in the background.
The image was taken by Curiosity's Mast Camera on the 32nd Martian day, or sol, of operations on the surface (Sept. 7, 2012, PDT or Sept. 8, 2012, UTC). APXS can be seen in the middle of the picture. This image let researchers know that the APXS instrument had not become caked with dust during Curiosity's dusty landing. Scientists enhanced the color in this version to show the Martian scene as it would appear under the lighting conditions we have on Earth, which helps in analyzing the terrain.
JPL confirms that the APXS "Works great, good confirmation with the calibration target." And "There might be tweaking needed because of contamination," but scientists have all the tools they need working perfectly.
Tomorrow, a final set of checkouts, and special imaging events with cameras. Then, "drive, drive, drive," until the science team decides where to stop. Scientists packed a piece of Earth to take to Mars -- specifically, a chunk of New Mexico.
A sample of basaltic rock from a lava flow in New Mexico serves as a calibration target carried on the front of NASA's Mars rover Curiosity for the rover's Canadian-made Alpha Particle X-Ray Spectrometer (APXS) instrument. This image of the APXS calibration target was taken by the rover's Mars Hand Lens Imager (MAHLI) during the 34th Martian day, or sol, of Curiosity's work on Mars (Sept. 9, 2012). The image has been rotated to compensate for the tilted orientation of the camera when it was taken.
The prepared slab of well-characterized dark rock collected near Socorro, N.M., is held in a nickel mounting. The circular opening revealing the rock is about 1.4 inches (3.5 centimeters) in diameter. The Sol 34 imaging was part of characterization testing of the rover's arm and tools on the arm. A subsequent step commanded the arm-mounted APXS instrument to take a reading of the composition of the calibration target. Curiosity will use the target from time to time during the mission, checking the continuing performance and calibration of the APXS instrument.
APXS can identify chemical elements in rocks and soils. The spectrometer uses the radioactive element curium as a source to bombard the target with energetic alpha particles (helium nuclei) and X-rays. This causes each element in the target to emit its own characteristic X-rays, which are then registered by an X-ray detector chip inside the instrument's sensor head.
The rock in the calibration target is the hardest basalt of more than 200 types tested by the APXS team. Hardness was a desired attribute for preventing the target from breaking during the stresses of launch and landing. In addition, this basalt is low in sulfur, nickel and chlorine. Those elements are common in Martian dust. Thus, scientists using APXS will more easily detect and account for any Martian dust on the calibration target.
In the image below cropped from a larger scene by the Mars Hand Lens Imager (MAHLI), a penny with the first close-up images of Martian sand grains, seen right below Lincoln's ear (about 200 microns in size, or .2 mm) and one near the number 9 (about 100 microns, or .1 mm).
What science can we determine from this image? Edgett replies: The little sand grains on the penny are "just things that blew up on the penny during landing." They haven't been transported far, because if they were more round they'd have originated from a greater distance.
This is the first penny ever sent to Mars, and it was minted in the first year on which Lincoln's image was present on the coin.
One JPL scientist on the call, fumbling for a precise sol number as he describes an image, stops and says "Man, I am so tired." They've been on "Mars Time," following the daily solar cycles that Curiosity is on, and experiencing slow-motion sleep deprivation.
The most common type of rock on Mars is basalt, so that is what they're aiming for with the first gathering of samples in the days (and sols) to come.
And a little easter egg: The spaces in the tire treads in the image below are Morse Code for "J-P-L."
This view of the three left wheels of NASA's Mars rover Curiosity combines two images that were taken by the rover's Mars Hand Lens Imager (MAHLI) during the 34th Martian day, or sol, of Curiosity's work on Mars (Sept. 9, 2012). In the distance is the lower slope of Mount Sharp.
The camera is located in the turret of tools at the end of Curiosity's robotic arm. The Sol 34 imaging by MAHLI was part of a week-long set of activities for characterizing the movement of the arm in Mars conditions.
The main purpose of Curiosity's MAHLI camera is to acquire close-up, high-resolution views of rocks and soil at the rover's Gale Crater field site. The camera is capable of focusing on any target at distances of about 0.8 inch (2.1 centimeters) to infinity, providing versatility for other uses, such as views of the rover itself from different angles.
And above, a new image from Curiosity showing the open inlet where rock and soil samples will be funneled down for analysis. This photograph was captured by (MAHLI) on Curiosity's 36th Martian day, or sol, of operations on Mars (Sept. 11, 2012).
MAHLI was about 8 inches (20 centimeters) away from the mouth of the Chemistry and Mineralogy (CheMin) instrument when it took the picture. The entrance of the funnel is about 1.4 inches (3.5 centimeters) in diameter. The mesh screen is about 2.3 inches (5.9 centimeters) deep. The mesh size is 0.04 inches (1 millimeter). Once the samples have gone down the funnel, CheMin will be shooting X-rays at the samples to identify and quantify the minerals.
Engineers and scientists use images like these to check out Curiosity's instruments. This image is a composite of eight MAHLI pictures acquired at different focus positions and merged onboard the instrument before transmission to Earth; this is the first time the MAHLI performed this technique since arriving at Curiosity's field site inside Gale Crater. The image also shows angular and rounded pebbles and sand that were deposited on the rover deck during landing on Aug. 5, 2012 PDT (Aug. 6, 2012 EDT).
Like Burning Man, the ethos for rovers on Mars is "leave no trace." A journalist from Germany on the teleconference asks if the rover's activity will violate any internationally-agreed planetary protection agreements. A NASA headquarters spokesman says, "Curiosity is the cleanest rover NASA has ever sent to Mars. No prohibitions against planned drilling activity, based on what we expect the rover will do and where it will go."