 NASA's Curiosity rover found evidence for what scientists believe was an ancient, flowing stream on Mars at a few sites, including the rock outcrop pictured here. The key evidence for the ancient stream comes from the size and rounded shape of the gravel in and around the bedrock, according to the Jet Propulsion Laboratory/Caltech science team. The rounded shape leads the science team to conclude they were transported by a vigorous flow of water. The grains are too large to have been moved by wind. Curiosity arrived on Mars on August 6 and began beaming back images from the surface. See all the images here as they are released. Check out images from previous Mars missions.  This photos shows an up-close look at an outcrop that also shows evidence of flowing water, according to the JPL/Caltech science team. The outcrop's characteristics are consistent with rock that was formed by the deposition of water and is composed of many smaller rounded rocks cemented together. Water transport is the only process capable of producing the rounded shape of conglomerate rock of this size.  Curiosity completed its longest drive to date on September 26. The rover moved about 160 feet east toward the area known as "Glenelg." The rover has now moved about a quarter-mile from its landing site.  This image shows the robotic arm of NASA's Mars rover Curiosity with the first rock touched by an instrument on the arm. The photo was taken by the rover's right navigation camera.  This image combines photographs taken by the rover's Mars Hand Lens Imager at three distances from the first Martian rock that NASA's Curiosity rover touched with its arm. The images reveal that the target rock has a relatively smooth, gray surface with some glinty facets reflecting sunlight and reddish dust collecting in recesses in the rock.  This rock will be the first target for Curiosity's contact instruments. Located on a turret at the end of the rover's arm, the contact instruments include the Alpha Particle X-Ray Spectrometer for reading a target's elemental composition and the Mars Hand Lens Imager for close-up imaging.  Researchers used the Curiosity rover's mast camera, on September 7, to take a photo of the Alpha Particle X-Ray Spectrometer. The image was used to see if it had been caked in dust during the landing.  Researchers also used the mast camera to examine the Mars Hand Lens Imager (MAHLI) on the rover to inspect its dust cover and check that its LED lights were fucntional. In this image, taken on September 7, the MAHLI is in the center of the screen with its LED on. The main purpose of Curiosity's MAHLI camera is to acquire close-up, high-resolution views of rocks and soil from the Martian surface.  This is the open inlet where powdered rock and soil samples will be funneled down for analysis. The image is made up of eight photos taken on Spetember 11, by MAHLI and is used to check that the instrument is operating correctly.  This is the calibration target for the MAHLI. This image, taken on September 9, shows that the surface of the calibration target is covered with a layor of dust as a result of the landing. The calibration target includes color references, a metric bar graphic, a penny for scale comparison, and a stair-step pattern for depth calibration.  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 on Sunday, September 9, the 34th Martian day of Curiosity's work on Mars. In the distance is the lower slope of Mount Sharp.  This view of the lower front and underbelly areas of NASA's Mars rover Curiosity was taken by the rover's Mars Hand Lens Imager on Sunday. Also visible are the hazard avoidance cameras on the front of the rover.  The penny in this image is part of a camera calibration target on NASA's Mars rover Curiosity. The image was taken by the Mars Hand Lens Imager camera on Sunday.  The reclosable dust cover on Curiosity's Mars Hand Lens Imager was opened for the first time on Saturday, September 8, enabling MAHLI to take this image.  Curiosity rover used a camera located on its arm to obtain this self-portrait on Friday, September 7. The image of the top of Curiosity's Remote Sensing Mast, showing the Mastcam and Chemcam cameras, was taken by the Mars Hand Lens Imager. The angle of the frame reflects the position of the MAHLI camera on the arm when the image was taken. The image was acquired while MAHLI's c lear dust cover was closed.  The left eye of the Mast Camera on NASA's Mars rover Curiosity took this image of the rover's arm on Wednesday, September 5.  Sub-image one of three shows the rover and its tracks after a few short drives. Tracking the tracks will provide information on how the surface changes as dust is deposited and eroded.  Sub-image two shows the parachute and backshell, now in color. The outer band of the parachute has a reddish color.  Sub-image three shows the descent stage crash site, now in color, and several distant spots (blue in enhanced color) downrange that are probably the result of distant secondary impacts that disturbed the surface dust.  An image released Monday, August 27, was taken with Curiosity rover's 100-millimeter mast camera, NASA says. The image shows Mount Sharp on the Martian surface. NASA says the rover will go to this area.  The Mars rover Curiosity moved about 15 feet forward and then reversed about 8 feet during its first test drive on Wednesday, August 22. The rover's tracks can be seen in the right portion of this panorama taken by the rover's navigation camera.  NASA tested the steering on its Mars rover Curiosity on Tuesday, August 21. Drivers wiggled the wheels in place at the landing site on Mars.  Curiosity moved its robot arm on Monday, August 20, for the first time since it landed on Mars. "It worked just as we planned," said JPL engineer Louise Jandura in a NASA press release. This picture shows the 7-foot-long (2.1-meter-long) arm holding a camera, a drill, a spectrometer, a scoop and other tools. The arm will undergo weeks of tests before it starts digging.  With the addition of four high-resolution Navigation Camera, or Navcam, images, taken on August 18, Curiosity's 360-degree landing-site panorama now includes the highest point on Mount Sharp visible from the rover. Mount Sharp's peak is obscured from the rover's landing site by this highest visible point.  This composite image, with magnified insets, depicts the first laser test by the Chemistry and Camera, or ChemCam, instrument aboard NASA's Curiosity Mars rover. The composite incorporates a Navigation Camera image taken prior to the test, with insets taken by the came ra in ChemCam. The circular insert highlights the rock before the laser test. The square inset is further magnified and processed to show the difference between images taken before and after the laser interrogation of the rock.  An updated self-portrait of the Mars rover Curiosity, showing more of the rover's deck. This image is a mosiac compiled from images taken from the navigation camera. The wall of Gale Crater, the rover's landing site, can be seen at the top of the image.  This image shows what will be the rover's first target with it's chemistry and camera (ChemCam) instrument. The ChemCam will fire a laser at the rock, indicated by the black circle. The laser will cause the rock to emit plasma, a glowing, ionized gas. The rover will then analyze the plasma to determine the chemical composition of the rock.  This is a close-up of the rock that will be the ChemCam's first target.  This image, cropped from a larger panorama, shows an area, near the rover's rear left wheel, where the surface material was blown away by the descent-stage rockets.  This image, with a portion of the rover in the corner, shows the wall of Gale Crater running across the horizon at the top of the image.  This image, taken from the rover's mast camera, looks south of the landing site toward Mount Sharp.  This partial mosaic from the Curiosity rover shows Mars' environment around the rover's landing site on Gale Crater. NASA says the pictured landscape resembles portions of the U.S. Southwest. The high-resolution mosaic includes 130 images, but not all the ima ges have been returned by the rover to Earth. The blackened areas of the mosaic are the parts that haven't been transmitted yet. See more on this panaroma on NASA's site.  In this portion of the larger mosaic from the previous frame, the crater wall can be seen north of the landing site, or behind the rover. NASA says water erosion is believed to have created a network of valleys, which enter Gale Crater from the outside here.  In this portion of the larger mosaic from the previous frame, the crater wall can be seen north of the landing site, or behind the rover. NASA says water erosion is believed to have created a network of valleys, which enter Gale Crater from the outside here.  Two blast marks from the descent stage's rockets can be seen in the center of this image. Also seen is Curiosity's left side. This picture is a mosaic of images taken by the rover's navigation cameras.  A color image from NASA's Curiosity rover shows the pebble-covered surface of Mars. This panorama mosaic was made of 130 images of 144 by 144 pixels each. Selected full frames from this panorama, which are 1,200 by 1,200 pixels each, are expected to be transmitted to Earth later.  A panoramic photograph shows the Curiosity rover's surroundings at its landing site inside Gale Crater. The rim of Gale Crater can be seen to the left, and the base of Mount Sharp is to the center-right.  A partial view of a 360-degree color panorama of the Curiosity rover's landing site on Gale Crater. The panorama comes from low-resolution versions of images taken Thursday, August 9, with a 34-millimeter mast camera. Cameras mounted on Curiosity's remote sensing mast have beamed back fresh images of the site.  NASA's Curiosity rover took this self-portrait using a camera on its newly deployed mast.  A close-up view of an area at the NASA Curiosity landing site where the soil was blown away by the thrusters during the rover's descent on August 6. The excavation of the soil reveals probable bedrock outcrop, which shows the shallow depth of the soil in this area.  This color full-resolution image showing the heat shield of NASA's Curiosity rover was obtained during descent to the surface of Mars on Monday, August 13. The image was obtained by the Mars Descent Imager instrument known as MARDI and shows the 15-foot diameter heat shield when it was about 50 feet from the spacecraft.  This first image taken by the Navigation cameras on Curiosity shows the rover's shadow on the surface of Mars.  The color image captured by NASA's Mars rover Curiosity on Tuesday, August 7, has been rendered about 10% transparent so that scientists can see how it matches the simulated terrain in the background.  This image comparison shows a view through a Hazard-Avoidance camera on NASA's Curiosity rover before and after the clear dust cover was removed. Both images were taken by a camera at the front of the rover. Mount Sharp, the mission's ultimate destination, looms ahead.  The four main pieces of hardware that arrived on Mars with NASA's Curiosity rover were spotted by NASA's Mars Reconnaissance Orbiter. The High-Resolution Imaging Science Experiment camera captured this image about 24 hours after landing.  This image is a 3-D view in front of NASA's Curiosity rover. The anaglyph was made from a stereo pair of Hazard-Avoidance Cameras on the front of the rover. Mount Sharp, a peak that is about 3.4 miles high, is visible rising above the terrain, though in one "eye" a box on the rover holding the drill bits obscures the view.  This view of the landscape to the north of NASA's Mars rover Curiosity was acquired by the Mars Hand Lens Imager on Monday afternoon on the first day after landing.  This view of the landscape to the north of NASA's Mars rover Curiosity was acquired by the Mars Hand Lens Imager on Monday afternoon, the first day after landing.  This is one of the first pictures taken by Curiosity after it landed. It shows the rover's shadow on the Martian soil.  Another of the first images taken by the rover. The clear dust cover that protected the camera during landing has popped open. Part of the spring that released the dust cover can be seen at the bottom right, near the rover's wheel.  This image shows Curiosity's main science target, Mount Sharp. The rover's shadow can be seen in the foreground. The dark bands in the distances are dunes.  Another of the first images beamed back from NASA's Curiosity rover on August 6 is the shadow cast by the rover on the surface of Mars.  NASA's Mars Curiosity Rover, shown in this artist's rendering, touched down on the planet on August 6.                                                     
(CNN) -- If the Curiosity rover had been sent to Mars in ancient times, it might have found itself sinking in a stream. The 2,000-pound super-rover, which made its now-legendary landing on Mars on August 6, has come across stones in conglomerate rock suggesting that water must have flowed there in the past. One such rock outcrop is called Hottah, after Hottah Lake in Canada's Northwest Territories. It looks like someone took a jackhammer and lifted up a sidewalk, said John Grotzinger, lead scientist for the Curiosity mission, at a press conference Thursday. The consensus is that "this is a rock that was formed in the presence of water," Grotzinger said. "We can characterize that water as being a vigorous flow." In and around this bedrock, Curiosity has come across rounded gravels. The rocks appear to have been subjected to a sediment transport process, carried by either water or wind, said scientist Rebecca Williams of the Planetary Science Institute in Tucson, Arizona. The gravels seem too large to have been transported by wind, meaning it's likely that this is a stream bed. A second rock outcrop, called Link, holds similar evidence. Scientists used data from Curiosity and the orbiters at Mars to enhance their understanding of the area. The water flowing in these rock formations was probably somewhere between ankle and hip deep, said Curiosity science co-investigator William Dietrich of the University of California, Berkeley. What we've done on Mars, and what's next Scientists believe the water and sediment flowed down the crater into an alluvial fan -- a geological formation created by material that water transports. At least intermittently, this fan appears to have extended down to the area where the rover landed. It's hard to say how long ago this water flowed -- an estimate would be "thousands to millions of years," Dietrich said. Previously, scientists have used data from past Mars missions to speculate about channels on the planet, and whether water could have flowed in them. This is the first direct observation of streambed material, Dietrich said. There are no plate tectonics on Mars, meaning the planet does not have moving plates underneath the surface that cause quakes. So why does this Hottah rock formation look the way it does? Grotzinger hypothesizes that "Somewhere near this outcrop, a small impact occurred and lifted the beds up and rotated them," he said. The rover did not employ any of its chemistry tools to examine the area; rather, scientists made their judgments about the rocks based on photos. Curiosity is now three-quarters of the way between Hottah and Glenelg, its next official stop. Glenelg was chosen as a target because it has three types of terrain, including layered bedrock, making it a potentially interesting place for Curiosity to try out its drill. An unsolved mystery is whether life could have been supported on Mars. Water is a necessary ingredient, but an energy source and carbon are also essential. Curiosity can detect organic molecules and tear them apart to deliver details about them back to Earth, but they would still not be definitive evidence that life existed. Such molecules can come from nonliving sources, and Curiosity doesn't have the technology to make that distinction. That will have to wait for another mission. This rover's ultimate destination is Mount Sharp, a 3-mile-high mountain with layers of sediment that will provide more opportunities to search for organic molecules. Curiosity recently tested out its contact instruments on a rock called Jake Matijevic. It used its Alpha Particle X-Ray Spectrometer (APXS) instrument to touch the rock, and the Mars Hand Lens Imager (MAHLI) to take close-up photos. Another instrument, ChemCam, shot laser pulses at the rock and finished its testing on Monday. The $2.6 billion mission is slated to last for two years, but previous rovers have far outlasted their estimated lifetimes. The Spirit rover operated from 2004 to 2010, and the Opportunity rover has been chugging along since 2004. These twin rovers had initial mission periods of only 90 days.   |
9/27/2012
Rover finds evidence of ancient water on Mars
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