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Thousands of craters made by WWII bombs dropped by Allies on Nazi fuel sites are uncovered in Poland

Daily Mail - Science & tech

Poland still bears the scars from thousands of bombs that hit the nation in WWII – and a new map has uncovered 6,000 of the impact sites. Researchers at the University of Silesia used LIDAR technology to map the Koźle Basin, allowing them to peer through vegetation and see impact sites across and deep within the ground. The craters ranged in size from 16 to 49 feet in diameter, with some parts found with up to 30 craters in just one acre of land. The craters are a reminder of the historical event, but the impact sites have also intertwined with nature over the past 75 years, turning into bodies of water and homes for wildlife. The bombs were dropped by Allied planes above Koźle Basin, which at the time of WWII was occupied by Nazi soldiers and home to a number of their fuel production plants.


Perseverance will explore history of ancient lake

Science

Last week, NASA's $2.7 billion Perseverance rover made a picture-perfect landing on the floor of Mars's Jezero crater, which scientists believe was filled to the brim with water 3.8 billion years ago. Two kilometers away looms the rover's primary target: a fossilized river delta, created as muddy water spilled into the crater—ideal for preserving signs of life. But before Perseverance starts the long climb up into the delta, to drill samples that will eventually be returned to Earth, it will examine the rocks beneath its six aluminum wheels. The rover landed near outcrops of rock layers that may have originally been laid down before and after the lake and the delta. The NASA team will probe them for clues to the nature and timing of the brief period when water flowed—and life might have flourished. Even the first images returned to Earth, grainy and taken from the underneath the rover, left the team elated, says Katie Stack Morgan, the mission's deputy project scientist at NASA's Jet Propulsion Laboratory (JPL). “We have enough for the scientists to really sink their teeth into.” The rover's arrival at Mars was filled with nail-biting drama, even as the precise, autonomous descent unfolded like clockwork. After the spacecraft plunged by parachute through the thin air, a rocket-propelled hovercraft took over, seeking a boulder-free spot before lowering the rover from nylon cords. The final moments, captured in breathtaking detail by cameras below the hovercraft, show the rover landing in a cloud of dust. “We did have a pretty clean run,” says Allen Chen, head of the rover's landing team at JPL, in a dry understatement. “It did what it had to do.” The touchdown marks NASA's ninth successful landing on the martian surface out of 10 tries. ![Figure][1] GRAPHIC: C. BICKEL/ SCIENCE After 3 days, the rover had executed 5000 commands and scientific instruments were certifying their health, says Jessica Samuels, an engineer and mission manager at JPL. “Everything is coming back exactly how we want it to.” The rover raised its camera mast 2 meters above the surface to capture a panorama of its surroundings. After several days updating software, the team plans to wiggle the rover's wheels and conduct a short test drive. The rover will also extend its five-jointed, 2-meter-long robotic arm, which carries the rover's coring drill and several more cameras, and put it through some calisthenics. A second robotic arm, designed to manipulate a cache of dust and rock samples inside the rover, will be run through its paces. Stored in 43 ultraclean tubes, those samples represent the start of a multibillion-dollar, multinational effort to collect martian rocks and return them for analysis on Earth; two follow-up missions to retrieve the samples are planned for later this decade ( Science , 22 November 2019, p. [932][2]). Within its first 2 years, the rover is expected to fill nearly half the tubes on its trek of more than 10 kilometers to the crater's rim. The rest will be filled in an extended mission, as the rover trundles beyond the crater to ancient highlands thought to have once held geothermal springs. Perseverance's primary mission is to search for evidence of past life, captured in the delta mudstones and other rocks likely to preserve organic molecules—or even fossilized life. But interpreting this evidence will also require a better understanding of Mars's climatic past, from clues that can be collected right away by the rover. The first opportunity to drill a sample could come within a few months, on the flat, pebble-strewn terrain where Perseverance landed. Some scientists believe these rocks are from an ancient lava flow that erupted long after the lake disappeared, arguing that they look the way Hawaiian flows might if bombarded by meteorites and whipped by winds for several billion years. But when Perseverance's predecessor, the Curiosity rover, explored similar rocks in Gale crater and its ancient lake, most of what scientists had thought were lava fields turned out to be sedimentary rocks: ground up volcanic bits ferried by water and deposited in layers, presumably in the vanished lake. The early pictures from Perseverance are difficult to interpret: Rocks riddled with holes could be pumice, porous from gas escaping from cooling lava, or they could be sedimentary rocks, perforated over time by water. Bigger boulders in the distance look like ancient volcanic rocks: dark and coated by a light-colored dust. Fortunately, Perseverance's scientific instruments are designed to pin down the rocks' origin. Cameras on the mast could spy distinctive angular striped layers, called cross-bedding, that only form when deposited as sediments. A camera mounted on the end of the rover's robotic arm for microscopic views could capture the grain of minerals: Sedimentary rocks, for example, are typically rounded by their watery travels. Two other instruments on the arm will fire x-rays and ultraviolet laser light at rock samples, provoking reactions that could reveal chemical fingerprints of volcanic or sedimentary rocks. It's a crucial distinction. If the rocks are volcanic—either lava deposits or, more likely, ash from a distant eruption—they'll contain trace radioactive elements that decay at a certain rate, so when samples are returned to Earth, lab scientists could date the eruption and put a bound on the age of the lake. Any date will also help pin down the highly uncertain overall martian timeline, currently dated by counting the number of craters on a given terrain. (Older surfaces are pocked with more craters.) Sampling such a volcanic rock would “provide a critical anchor to the timing of events we are looking at,” says Ken Farley, the mission's project scientist and a geologist at the California Institute of Technology. The rover's initial path is likely to cross another intriguing target just 250 meters away on the crater floor: outcrops that, from orbit, appear rich in both olivine, a volcanic mineral, and carbonates, which can form when olivine is exposed to water and carbon dioxide. If this layer is volcanic ash from an eruption that preceded the Jezero lake, radioactive dates from it and the potential volcanic layer deposited on the lakebed should bracket the lake's existence in time. Moreover, isotopes of oxygen in the carbonates could reveal the temperature of the water that formed the mineral; balmy water would suggest Mars was once warm and wet for millions of years at a time, whereas water near freezing would argue for sporadic bursts of warmth. The carbonate might even contain gas bubbles—samples of the ancient martian atmosphere, which could allow scientists to see whether it held methane or other greenhouse gases that would have warmed early Mars. “That obviously would be game changing,” says Timothy Goudge, a planetary scientist at the University of Texas, Austin, who led the team that made the case for Jezero as a landing site. There will be no drilling at the landing site itself. But there will be flying. After the monthlong commissioning phase is over, the team will find a nearby, flat spot to loose the 1.8-kilogram Ingenuity helicopter, which survived the landing attached to the rover's belly. With a fuselage the size of a tissue box, Ingenuity is a technology demonstration, a bid to fly a rotor-powered vehicle on another planet for the first time. After being dropped to the surface, the helicopter will furiously spin its rotors to ascend 3 meters in the air for 20 seconds. Four additional, higher flights could follow, over a total of 30 days, says MiMi Aung, Ingenuity's project manager at JPL. On later flights the helicopter could collect reconnaissance images for terrain off the rover's main path. “It will be truly a Wright brothers moment,” Aung says, “but on another planet.” [1]: pending:yes [2]: http://www.sciencemag.org/content/366/6468/932


NASA Is Training an AI to Detect Fresh Craters on Mars

WIRED

For the past 15 years, NASA's Mars Reconnaissance Orbiter has been doing laps around the Red Planet studying its climate and geology. Each day, the orbiter sends back a treasure trove of images and other sensor data that NASA scientists have used to scout for safe landing sites for rovers and to understand the distribution of water ice on the planet. Of particular interest to scientists are the orbiter's crater photos, which can provide a window into the planet's deep history. NASA engineers are still working on a mission to return samples from Mars; without the rocks that will help them calibrate remote satellite data with conditions on the surface, they must do a lot of educated guesswork when it comes to determining each crater's age and composition. For now, they need other ways to tease out that information.


China's Chang'e 5 is bringing back the first moon rocks in 44 years

New Scientist

Chang'e 5 is on the last leg of its mission on the moon. After a visit to the lunar surface lasting less than 48 hours, it is back in orbit around the moon and ready to bring its samples home so that scientists on Earth can analyse them. The spacecraft consists of an orbiter, re-entry capsule, a lander and ascent stage, and launched on 23 November aboard a Long March 5 rocket. It landed on the moon on 1 December. It is China's first sample return mission, making the nation only the third – after the US and the Soviet Union – to bring back rocks and dust from the moon.


China has launched its most advanced mission to the moon yet

New Scientist

China launched its Chang'e 5 spacecraft on 23 November, in the first mission designed to bring moon rocks back to Earth in more than four decades. The uncrewed Chang'e 5 probe will attempt to collect at least 2 kilograms of lunar dust and debris from the northern region of the Oceanus Procellarum, a previously unvisited area on the near side of the moon. If successful, the Chang'e 5 return mission will make China only the third country, after the US and the Soviet Union, to have retrieved samples from the moon. The last sample return mission was carried out in 1976 by the Soviet Union's Luna 24 robotic probe, which brought back around 170 grams to Earth. The Chang'e 5 launch happened early on Tuesday morning, Beijing time, from a Long March 5 rocket at a site in Wenchang on Hainan Island in the South China Sea.


NASA taps AI to identify "fresh craters" on Mars

#artificialintelligence

The Mars Reconnaissance Orbiter's HiRISE camera captured this impact crater on Mars. On July 15, 1965, the Mariner 4 spacecraft snapped a series of photographs of Mars during its flyby of the Red Planet. These were the first "close-up" images taken of another planet from outer space, according to NASA. One of these first grainy photographs depicted a massive crater nearly 100 miles in diameter. Now, NASA's Jet Propulsion Laboratory (JPL) is tapping artificial intelligence (AI) to help with its cosmic cartography efforts, using these technologies to identify "fresh craters" on Mars.


Artificial intelligence helps classify new craters on Mars – IAM Network

#artificialintelligence

An innovative artificial intelligence (AI) tool developed by NASA has helped identify a cluster of craters on Mars that formed within the last decade.The new machine-learning algorithm, an automated fresh impact crater classifier, was created by researchers at NASA's Jet Propulsion Laboratory (JPL) in California -- and represents the first time artificial intelligence has been used to identify previously unknown craters on the Red Planet, according to a statement from NASA. Scientists have fed the algorithm more than 112,000 images taken by the Context Camera on NASA's Mars Reconnaissance Orbiter (MRO). The program is designed to scan the photos for changes to Martian surface features that are indicative of new craters. In the case of the algorithm's first batch of finds, scientists think these craters formed from a meteor impact between March 2010 and May 2012. Related: Latest photos from NASA's Mars Reconnaissance Orbiter"AI can't do the kind of skilled analysis a scientist can," Kiri Wagstaff, JPL computer scientist, said in the statement.


Artificial intelligence helps classify new craters on Mars

#artificialintelligence

An innovative artificial intelligence (AI) tool developed by NASA has helped identify a cluster of craters on Mars that formed within the last decade. The new machine-learning algorithm, an automated fresh impact crater classifier, was created by researchers at NASA's Jet Propulsion Laboratory (JPL) in California -- and represents the first time artificial intelligence has been used to identify previously unknown craters on the Red Planet, according to a statement from NASA. Scientists have fed the algorithm more than 112,000 images taken by the Context Camera on NASA's Mars Reconnaissance Orbiter (MRO). The program is designed to scan the photos for changes to Martian surface features that are indicative of new craters. In the case of the algorithm's first batch of finds, scientists think these craters formed from a meteor impact between March 2010 and May 2012.


NASA's OSIRIS-REx Is About to Touch an Asteroid

WIRED

For nearly two years, a small spacecraft called OSIRIS-REx has been orbiting an asteroid more than 100 million miles away, patiently biding its time by studying the rock's surface. Scientists believe that this asteroid, Bennu, is a piece of a much larger one that formed just a few million years after Earth. It's a perfectly preserved cosmic time capsule that could reveal the secrets of the ancient history of our solar system. Tomorrow, OSIRIS-REx will make a daring plunge to Bennu's surface and use a robotic arm to vacuum up some of its space dust, which it'll bring back to Earth. The encounter will last for just a few seconds, but it is a technological feat that has been more than a decade in the making.


NASA Unveils a Cluster of Mars Craters Discovered by AI

#artificialintelligence

A team of planetary scientists and AI researchers at NASA's Jet Propulsion Laboratory in Southern California tapped artificial intelligence to identify fresh craters on Mars. The High-Resolution Imaging Science Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance Orbiter (MRO) spotted the craters. AI technology first discovered the craters in images taken the orbiter's Context Camera, then scientists followed up with the HiRISE image to confirm the craters. The accomplishment offers hope for both saving times and accelerating the volume of findings, as noted by NASA's Jet Propulsion Laboratory. According to the laboratory, scientists typically spend hours each day studying images captured by NASA's MRO, looking for changing surface phenomena like dust devils, avalanches, and shifting dunes.