When NASA's rover Curiosity entered the Martian atmosphere to begin its famous "7 minutes of terror," one component of its entry, descent and landing (EDL) included the deployment of a huge parachute to capture the thin Mars air to aid its rapid deceleration. Shortly after landing inside Gale Crater on Aug. 5, 2012, NASA's orbiting Mars Reconnaissance Orbiter managed to photograph not only the parachute, but also the backshell, heat shield, skycrane and counterweights.
Now, the team managing one of the MRO's instruments - the High-Resolution Imaging Science Experiment (HiRISE) - have released a series of photos of Curiosity's parachute over the course of five months.
Mars' atmosphere can be up to 1,000 times thinner than Earth's, so although the red planet experiences global dust storms and small-scale dust devils, the Martian wind at its most fierce won't exactly knock you off your feet. But for Curiosity's discarded parachute, the wind is strong enough to cause it to flap around.
"Sometime between September 8, 2012 and November 30, 2012, there was a major change in which the parachute extension to the southeast (lower right) was moved inward, so the parachute covers a smaller area," observes Alfred McEwen, planetary geologist at the University of Arizona in Tucson and HiRISE principal investigator. "In the same time interval some of the dark ejecta around the backshell brightened, perhaps from deposition of airborne dust."
McEwen also points to another windy event between Dec. 16, 2012 and Jan. 13, 2013, which caused the parachute to shift to the southeast.
BIG PIC: Curiosity's Cruise Stage Impact Craters Spotted
Apart from being a minor curiosity and a lovely reminder that we have satellites capable of observing temporal weather events on another planet, these flapping events may help explain why the Viking landers' parachutes still remain visible from orbit since their landing in 1976 - windy events dust-off the bright parachute material. Also, the motion of a large piece of fabric on the surface of Mars provides a direct view of the weather conditions on the ground, much like a windsock on an airfield provides pilots with general information about wind direction and speed.
"The parachute's suspension lines were made from Technora, with a fiber similar to Kevlar," adds McEwen. "The color is a creamy yellow, which is why they are not visible in the images such as those in the Phoenix lander descent image which were white."
Image credit: NASA/JPL/University of Arizona. Animation credit: NASA/JPL/University of Arizona - re-compiled and slightly adjusted by Ian O'Neill for clarity.
Mars Curiosity 'Litter Bug' Spied from Orbit
Aug. 7, 2012 --
NASA's Mars rover Curiosity was a bit of a litter bug as it wrapped up its 352-million mile (566-million kilometer) journey early Monday and headed toward a landing inside Gale Crater, an ancient impact basin that is home to a towering mound of sedimentary rock. From a vantage point about 186 miles (300 kilometers) above the planet, Mars Reconnaissance Orbiter, known by its acronym MRO, surveyed the scene, providing documentation (in case NASA ever faces littering charges) of Curiosity’s discarded heat shield, parachute and sky crane.
Curiosity The High-Resolution Imaging Science Experiment (HiRISE) on board the MRO captured this shot of Curiosity. The black streaks on either side of the rover are where lighter colored top soil was blasted away by the thrust of the rocket's on the sky crane flying platform.
Heat Shield The heat shield, which protected the vehicle as it blasted through Mars' atmosphere, ended up about three-quarters of a mile (1,200 meters) from Curiosity's landing spot on the north side of Gale Crater, which is located near the equator in Mars' southern hemisphere. The picture shows the heat shield in a region with lots of small craters, whereas Curiosity's landing area has more rounded hills and fewer smaller craters. To the north of both, is a third type of terrain that has lots of buttes, mesas and pits. "I don't know that the team has been talking about all night, but if it was up to me I would go to where those three come together, so we could start to get the flavor of what's going on here in terms of the different geologic materials," said Ken Edgett, one of the 420 Curiosity scientists.
Backshell and Parachute The backshell, which contained the rover’s 51-foot diameter parachute, is about 673 yards (615 meters) away.
Sky Crane The last part of the elaborate landing system, the sky crane, lowered Curiosity to the ground on a tether at 1:32 a.m. EDT then crash-landed 711 yards (650 meters) away.
The MRO will be angling for a better shot in five days and color images in the weeks and months to come, said MRO camera scientist Sarah Milkovich.
MORE: FULL COVERAGE OF THE MARS SCIENCE LABORATORY