NASA’s Curiosity rover is making great strides – or great wheel tracks rather – on its primary mission. The rover, which landed at Bradbury Landing late on August 5, is rolling along to the geologically interesting site called Glenelg the team will investigate before setting course to Mount Sharp. The rover still has a few hundred feet to go, but there’s no shortage of news from its traverse.The MSL team has never been able to give a solid timeframe for how long Curiosity will take to get to Glenelg. When planning the drive, the team also planned to stop along the way to investigate interesting looking rocks or scoop loose soil to do some contact science. Last Wednesday, September 19, NASA announced that it’s found Curiosity’s first contact science target on the drive: a rock called Jake.
Jake is named for engineer Jacob Matijevic, a JPL engineer who helped develop the surface operations behind previous rovers Sojourner, Spirit, and Opportunity. Matijevic was one of the first people who really believed in the possibility of long term exploration with rovers, and in the early days of the MER missions predicted that if the rovers could last for 6 months they’d probably last 6 years. He was instrumental in building the MSL mission, but died weeks after Curiosity’s landing on August 20. Jake the rock is smaller than Jake the man, just 10 inches tall and 16 inches wide. It was the rock’s shape that caught the attention of scientists. It’s an odd, pyramidal shape that almost looks like a tiny Pyramid of Giza. But the rock wasn’t likely carved by ancient, tiny Martians; it was likely carved by wind erosion. Over the weekend, Curiosity drove up close to the football sized rock and used its arm for the first contact science. Two instruments did the work: APXS and MAHLI. When the Alpha Particle X-ray Spectrometer instrument – APXS – is placed against a rock, it bombards it with X-rays and alpha particles (which are nuclei of helium atoms made of two protons and two neutrons). These interact with atoms in the rock to give off X-rays. APXS’s spectrometer analyzes the different energies of these X-ray emissions to determine the rock’s mineral composition. Curiosity’s Mars Hand Lens Imager, MAHLI, which sites on the same turret as APXS on the rover’s arm, takes close-up visual images of its target. On Sol 47, September 23 on Earth, both instruments set to work on the Jake rock.
Interesting sights aren’t just happening on the surface of Mars. Last week, Curiosity saw a partial Phobian eclipse, that is to say a transit of Mars’ moon Phobos across the disk of the Sun. Of the 1,000 shots the rover took with a neutral density filter on its Mastcam, 200 show the partial eclipse. And they aren’t just stunning pictures; they hold a wealth of information for those who know how to read them. Scientists will analyze the eclipse pictures to determine how Phobos’ orbit has changed over time, what effect the tiny moon has on Mars’ shape, and what the internal composition of planet and moon might be. The details of their findings will come when the team publishes its final report in a few months.
And finally in Curiosity news, a sight worth seeing on the rover itself. In a recent picture taken by the MAHLI on Sol 44, September 19 on Earth, the rover showed off a plaque affixed to the front left side of its deck. The rectangular plaque, made of anodized aluminum measuring 3.94 inches by 3.23 inches, bears an impressive list of signatures: Barack Obama, President, United States of America; Joe Biden, Vice President; John P. Holdren, Director, Office of Science and Technology Policy; Charles F. Bolden, Jr., Administrator, National Aeronautics and Space Administration; Edward J. Weiler, Associate Administrator, Science Mission Directorate (2008–2011); James Green, Director, Planetary Sciences Division; Doug McCuistion, Director, Mars Exploration Program; Michael Meyer, Program Scientist, Mars Exploration Program; David Lavery, Program Executive, Mars Science Laboratory.
Another image taken on the same sol shows an aluminum medallion bearing the stars and stripes of the American flag. There are four of these medallions on the rover, each slightly larger than 2.5 inches across. Called “mobility logos,” the other three bear NASA’s logo, JPL’s logo, and the MSL mission logo. And rightly so – this is a mission well worth taking great pride in!