- NASA Launches Four Magnetospheric Multiscale Spacecraft
- Russia Plans to Start Moon Exploration Jointly With Partners
- Curiosity Rover Arm Delivers Rock Powder Sample
- New Expandable Addition on Space Station to Gather Critical Data for Future Space Habitat Systems
- Jupiter's Moon Ganymede Has an Underground Ocean
- Russian Wayward Satellite Reaches Good Trajectory
- Milky Way May Be Much Larger Than Previously Estimated
- Some Habitable Exoplanets Could Experience Wildly Unpredictable Climates
- Scientists Capture Image of Sci-Fi Landing Site on Mars
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Posted: 13 Mar 2015 07:01 AM PDT
A United Launch Alliance (ULA) Atlas V rocket carrying the Magnetospheric Multiscale (MMS) payload for NASA lifted off from the Cape Canaveral Air Force Station Space Launch Complex 41 in Florida at 10:44 p.m. EDT on March 12, 2015. Following the successful launch, MMS spacecraft are positioned in Earth’s orbit to begin the first space mission dedicated to the study of a phenomenon called magnetic reconnection. This process is thought to be the catalyst for some of the most powerful explosions in our solar system. After reaching orbit, each spacecraft deployed from the rocket’s upper stage sequentially, in five-minute increments, beginning at 12:16 a.m. Friday, with the last separation occurring at 12:31 a.m. NASA scientists and engineers were able to confirm the health of all separated spacecraft at 12:40 a.m. "I am speaking for the entire MMS team when I say we’re thrilled to see all four of our spacecraft have deployed and data indicates we have a healthy fleet,” said Craig Tooley, project manager at NASA's Goddard Space Flight Center in Greenbelt, Maryland.
“It is our honor to launch this mission that will study the physics of magnetic reconnection. This energy process is one of the key drivers of space weather which affects communication networks, like GPS navigation and electrical power grids here on earth,” said Jim Sponnick, ULA vice president, Atlas and Delta Programs. “Congratulations to the NASA Launch Services Program team, the NASA Goddard Space Flight Center team, Southwest Research Institute, all of our mission partners and the entire MMS team on this successful launch of the MMS constellation.”
Over the next several weeks, NASA scientists and engineers will deploy booms and antennas on the spacecraft, and test all instruments. The observatories will later be placed into a pyramid formation in preparation for science observations, which are expected to begin in early September. “After a decade of planning and engineering, the science team is ready to go to work,” said Jim Burch, principal investigator for the MMS instrument suite science team at the Southwest Research Institute in San Antonio (SwRI). “We’ve never had this type of opportunity to study this fundamental process in such detail.” The mission will provide the first three-dimensional views of reconnection occurring in Earth's protective magnetic space environment, the magnetosphere. Magnetic reconnection occurs when magnetic fields connect, disconnect, and reconfigure explosively, releasing bursts of energy that can reach the order of billions of megatons of trinitrotoluene (commonly known as TNT). These explosions can send particles surging through space near the speed of light. Scientists expect the mission will not only help them better understand magnetic reconnection, but also will provide insight into these powerful events, which can disrupt modern technological systems such as communications networks, GPS navigation, and electrical power grids. By studying reconnection in this local, natural laboratory, scientists can understand the process elsewhere, such as in the atmosphere of the sun and other stars, in the vicinity of black holes and neutron stars, and at the boundary between our solar system's heliosphere and interstellar space.
The spacecraft will fly in a tight formation through regions of reconnection activity. Using sensors designed to measure the space environment at rates100 times faster than any previous mission.
“MMS is a crucial next step in advancing the science of magnetic reconnection – and no mission has ever observed this fundamental process with such detail,” said Jeff Newmark, interim director for NASA’s Heliophysics Division at the agency’s Headquarters in Washington. “The depth and detail of our knowledge is going to grow by leaps and bounds, in ways that no one can yet predict.” MMS is the fourth mission in the NASA Solar Terrestrial Probes Program. Goddard built, integrated and tested the four MMS spacecraft and is responsible for overall mission management and operations. The principal investigator for the MMS instrument suite science team is based at the SwRI. Science operations planning and instrument commanding are performed at the MMS Science Operations Center at the University of Colorado Boulder’s Laboratory for Atmospheric and Space Physics. Credit: NASA  | ||||
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Posted: 13 Mar 2015 05:19 AM PDT
Russia plans to start exploring Earth's moon alongside partners from other states, a senior Russian space official said Thursday. Last month, Russian space agency Roscosmos said it hoped to send manned missions to the Earth's natural satellite by 2030. "We are going to include the moon program on our agenda soon. We are discussing these issues together with our new partners," said Vladimir Mitin, a deputy head of the manned program department at Roscosmos.
The official did not specify which countries would be teaming up with Russia. Russian moon exploration plans include sending unmanned spacecraft both to the surface and into lunar orbit. In September 2014, Roscosmos said it was planning to launch a full-scale moon exploration program in 2016-2025. In October 2014, Lev Zeleny, head of the Russian Space Research Institute, said that the start of Russia's unmanned lunar program had been delayed until 2018. The former USSR was the first country to physically explore the moon when the Soviet Luna 2 spacecraft successfully landed in 1959. The last Soviet mission to reach the moon, Luna 24, successfully achieved its mission in 1976. Credit: sputniknews.com  | ||||
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Posted: 13 Mar 2015 05:00 AM PDT
NASA's Curiosity Mars rover used its robotic arm Wednesday, March 11, to sieve and deliver a rock-powder sample to an onboard instrument. The sample was collected last month before the team temporarily suspended rover arm movement pending analysis of a short circuit. The Chemistry and Mineralogy (CheMin) analytical instrument inside the rover received the sample powder. This sample comes from a rock target called "Telegraph Peak," the third target drilled during about six months of investigating the "Pahrump Hills" outcrop on Mount Sharp. With this delivery completed, the rover team plans to drive Curiosity away from Pahrump Hills in coming days.
"That precious Telegraph Peak sample had been sitting in the arm, so tantalizingly close, for two weeks. We are really excited to get it delivered for analysis," said Curiosity Project Scientist Ashwin Vasavada of NASA's Jet Propulsion Laboratory, Pasadena, California. The rover experienced a short circuit on Feb. 27 while using percussion action in its drill to shake sample powder from the drill into a sample-processing device on the arm. Subsequent testing at JPL and on Curiosity has identified the likely cause as a transient short in the motor for the drill's percussion action. During several tests on the rover in the past 10 days, the short was reproduced only one time -- on March 5. It lasted less than one one-hundredth of a second and did not stop the motor. Ongoing analysis will help the rover team develop guidelines for best use of the drill at future rock targets. The rover's path toward higher layers of Mount Sharp will take it first through a valley called "Artist's Drive," heading southwestward from Pahrump Hills. The sample-processing device on the arm is carrying Telegraph Peak sample material at the start of the drive, for later delivery into the Sample Analysis at Mars (SAM) suite of instruments. The delivery will occur after SAM prepares for receiving the sample. Curiosity's drill has used a combination of rotary and percussion action to collect samples from six rock targets since the rover landed inside Gale Crater in 2012. The first sampled rock, "John Klein," in the Yellowknife Bay area near the landing site, provided evidence for meeting the mission's primary science goal. Analysis of that sample showed that early Mars offered environmental conditions favorable for microbial life, including the key elemental ingredients for life and a chemical energy source such as used by some microbes on Earth. In the layers of lower Mount Sharp, the mission is pursuing evidence about how early Mars environments evolved from wetter to drier conditions. JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Science Laboratory project for NASA's Science Mission Directorate, Washington, and built the project's Curiosity rover. Credit: NASA  | ||||
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Posted: 13 Mar 2015 12:33 AM PDT
NASA and Bigelow Aerospace are preparing to launch an expandable habitat module to the International Space Station this year. The agency joined Bigelow Thursday at its Las Vegas facility to mark completion of the company’s major milestones. The Bigelow Expandable Activity Module, or BEAM, leverages key innovations in lightweight and compact materials, departing from a traditional rigid metallic structure. In its packed configuration aboard SpaceX’s Dragon spacecraft launched on a Falcon 9 rocket, the module will measure approximately 8 feet in diameter. Once attached to the space station’s Tranquility Node and after undergoing a series of hardware validations, the module will be deployed, resulting in an additional 565 cubic feet of volume — about the size of a large family camping tent — accessible by astronauts aboard the orbiting laboratory.
Expandable habitats could be a new way to dramatically increase the amount of volume available to astronauts while also enhancing protection against radiation and physical debris. Innovative advances in efficiency provided by expandable habitats may give the nation new options for extending human presence farther into the solar system, both in transit and on the surface of other worlds, while also supporting the development of innovative platforms for commercial use in low-Earth orbit.
In the next decade, NASA plans to extend human spaceflight from low-Earth orbit operations to “proving ground” operations in cis-lunar space orbiting the moon. In the proving ground, NASA and its partners will validate vital hardware, including deep space habitats, as well as operations and capabilities necessary to send humans on long-duration missions to Mars or other deep-space destinations in which they must operate independently from Earth. The International Space Station serves as the world's leading laboratory for conducting cutting-edge research and is the primary platform for technology development and testing in space to enable human and robotic exploration of destinations beyond low-Earth orbit, including asteroids and Mars.
“We’re fortunate to have the space station to demonstrate potential habitation capabilities like BEAM,” said Jason Crusan, director of Advanced Exploration Systems at NASA Headquarters in Washington. “Station provides us with a long-duration microgravity platform with constant crew access to evaluate systems and technologies we are considering for future missions farther into deep space.”
Once BEAM is attached to the Tranquility Node, the space station crew will perform initial systems checks before deploying the habitat. During the BEAM’s minimum two-year test period, crews will routinely enter to take measurements and monitor its performance to help inform designs for future habitat systems. Learning how an expandable habitat performs in the thermal environment of space and how it reacts to radiation, micrometeroids, and orbital debris will provide information to address key concerns about living in the harsh environment of space.
The BEAM is an example of NASA’s increased commitment to partnering with industry to enable the growth of the commercial use of space. Bigelow Aerospace is building on technology NASA conceived in the 1990s and licensed to the company. NASA and Bigelow Aerospace are each benefitting from the sharing of expertise, costs, and risks to pursue mutual goals.
The module is scheduled to launch on SpaceX’s eighth cargo resupply mission to the space station later this year.
Credit: NASA
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Posted: 12 Mar 2015 04:09 PM PDT
NASA's Hubble Space Telescope has the best evidence yet for an underground saltwater ocean on Ganymede, Jupiter's largest moon. The subterranean ocean is thought to have more water than all the water on Earth's surface. Identifying liquid water is crucial in the search for habitable worlds beyond Earth and for the search for life as we know it. "This discovery marks a significant milestone, highlighting what only Hubble can accomplish," said John Grunsfeld, assistant administrator of NASA's Science Mission Directorate at NASA Headquarters, Washington, D.C. "In its 25 years in orbit, Hubble has made many scientific discoveries in our own solar system. A deep ocean under the icy crust of Ganymede opens up further exciting possibilities for life beyond Earth."
Ganymede is the largest moon in our solar system and the only moon with its own magnetic field. The magnetic field causes aurorae, which are ribbons of glowing, hot electrified gas, in regions circling the north and south poles of the moon. Because Ganymede is close to Jupiter, it is also embedded in Jupiter's magnetic field. When Jupiter's magnetic field changes, the aurorae on Ganymede also change, "rocking" back and forth.
By watching the rocking motion of the two aurorae, scientists were able to determine that a large amount of saltwater exists beneath Ganymede's crust, affecting its magnetic field.
A team of scientists led by Joachim Saur of the University of Cologne in Germany came up with the idea of using Hubble to learn more about the inside of the moon.
"I was always brainstorming how we could use a telescope in other ways," said Saur. "Is there a way you could use a telescope to look inside a planetary body? Then I thought, the aurorae! Because aurorae are controlled by the magnetic field, if you observe the aurorae in an appropriate way, you learn something about the magnetic field. If you know the magnetic field, then you know something about the moon's interior."
If a saltwater ocean were present, Jupiter's magnetic field would create a secondary magnetic field in the ocean that would counter Jupiter's field. This "magnetic friction" would suppress the rocking of the aurorae. This ocean fights Jupiter's magnetic field so strongly that it reduces the rocking of the aurorae to 2 degrees, instead of 6 degrees if the ocean were not present.
Scientists estimate the ocean is 60 miles (100 kilometers) thick — 10 times deeper than Earth's oceans — and is buried under a 95-mile (150-kilometer) crust of mostly ice.
Scientists first suspected an ocean in Ganymede in the 1970s, based on models of the large moon. NASA's Galileo mission measured Ganymede's magnetic field in 2002, providing the first evidence supporting those suspicions. The Galileo spacecraft took brief "snapshot" measurements of the magnetic field in 20-minute intervals, but its observations were too brief to distinctly catch the cyclical rocking of the ocean's secondary magnetic field.
The new observations were done in ultraviolet light and could only be accomplished with a space telescope high above Earth's atmosphere, which blocks most ultraviolet light.
The team’s results are published online in the Journal of Geophysical Research: Space Physics on March 12.
NASA's Hubble Space Telescope is celebrating 25 years of groundbreaking science on April 24. It has transformed our understanding of our solar system and beyond, and helped us find our place among the stars. To join the conversation about 25 years of Hubble discoveries, use the hashtag #Hubble25.
Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington.
Credit: hubblesite.org
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Posted: 12 Mar 2015 03:44 PM PDT
Russia’s telecommunications satellite Express-AM6, which was placed into a wrong orbit in late October 2014, has reached the final orbit, the satellite manufacturing company said on Thursday. During the October 21, 2014 launch, the spacecraft was accidentally sent into the wrong orbit "the parameters of which have significant deviations in the altitude, inclination and eccentricity," said the Information Satellite Systems - Reshetnev Company based in Zheleznogorsk, in Eastern Siberia’s Krasnoyarsk Territory.
The company’s experts helped the satellite to move into the correct orbit "due to the resources of its electric propulsion."
The satellite will operate in the orbital position 53 degrees Eastern longitude after the testing of its efficient payload is completed.
At that orbital position, the new spacecraft would replace the Ekspress-AM22 satellite, which by that time had outlived its operational life.
The Express-AM6 is a satellite that provides communications and broadcasting services in Russia. The lifetime of the spacecraft is 15 years.
Credit: TASS
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Posted: 12 Mar 2015 03:14 PM PDT
The Milky Way galaxy is at least 50 percent larger than is commonly estimated, according to new findings that reveal that the galactic disk is contoured into several concentric ripples. The research, conducted by an international team led by Rensselaer Polytechnic Institute Professor Heidi Jo Newberg, revisits astronomical data from the Sloan Digital Sky Survey which, in 2002, established the presence of a bulging ring of stars beyond the known plane of the Milky Way. “In essence, what we found is that the disk of the Milky Way isn’t just a disk of stars in a flat plane—it’s corrugated,” said Heidi Newberg, professor of physics, applied physics, and astronomy in the Rensselaer School of Science. “As it radiates outward from the sun, we see at least four ripples in the disk of the Milky Way. While we can only look at part of the galaxy with this data, we assume that this pattern is going to be found throughout the disk.”
Importantly, the findings show that the features previously identified as rings are actually part of the galactic disk, extending the known width of the Milky Way from 100,000 light years across to 150,000 light years, said Yan Xu, a scientist at the National Astronomical Observatories of China (which is part of the Chinese Academy of Science in Beijing), former visiting scientist at Rensselaer, and lead author of the paper.
“Going into the research, astronomers had observed that the number of Milky Way stars diminishes rapidly about 50,000 light years from the center of the galaxy, and then a ring of stars appears at about 60,000 light years from the center,” said Xu. “What we see now is that this apparent ring is actually a ripple in the disk. And it may well be that there are more ripples further out which we have not yet seen.”
The research, funded in part by the National Science Foundation and titled “Rings and Radial Waves in the Disk of the Milky Way,” was published today in the Astrophysical Journal. Newberg, Xu, and their collaborators used data from the Sloan Digital Sky Survey (SDSS) to show an oscillating asymmetry in the main sequence star counts on either side of the galactic plane, starting from the sun and looking outward from the galactic center. In other words, when we look outward from the sun, the mid-plane of the disk is perturbed up, then down, then up, and then down again.
“Extending our knowledge of our galaxy’s structure is fundamentally important,” said Glen Langston, NSF program manager. “The NSF is proud to support their effort to map the shape of our galaxy beyond previously unknown limits.”
The new research builds upon a 2002 finding in which Newberg established the existence of the “Monoceros Ring,” an “over-density” of stars at the outer edges of the galaxy that bulges above the galactic plane. At the time, Newberg noticed evidence of another over-density of stars, between the Monoceros Ring and the sun, but was unable to investigate further. With more data available from the SDSS, researchers recently returned to the mystery.
“I wanted to figure out what that other over-density was,” Newberg said. “These stars had previously been considered disk stars, but the stars don’t match the density distribution you would expect for disk stars, so I thought ‘well, maybe this could be another ring, or a highly disrupted dwarf galaxy.”
When they revisited the data, they found four anomalies: one north of the galactic plane at 2 kilo-parsecs (kpc) from the sun, one south of the plane at 4-6 kpc, a third to the north at 8-10 kpc, and evidence of a fourth to the south 12-16 kpc from the sun. The Monoceros Ring is associated with the third ripple. The researchers further found that the oscillations appear to line up with the locations of the galaxy’s spiral arms. Newberg said the findings support other recent research, including a theoretical finding that a dwarf galaxy or dark matter lump passing through the Milky Way would produce a similar rippling effect. In fact, the ripples might ultimately be used to measure the lumpiness of dark matter in our galaxy.
“It’s very similar to what would happen if you throw a pebble into still water – the waves will radiate out from the point of impact,” said Newberg. “If a dwarf galaxy goes through the disk, it would gravitationally pull the disk up as it comes in, and pull the disk down as it goes through, and this will set up a wave pattern that propagates outward. If you view this in the context of other research that’s emerged in the past two to three years, you start to see a picture is forming.”
The research was funded by the NSF, as well as the Chinese National Science Foundation and the National Basic Research Program of China.
Newberg currently researches the structure and evolution of our own galaxy, using stars as tracers of the galactic halo and disks. These stars in turn are used to trace the density distribution of dark matter in the Milky Way. She has been a participant of the Sloan Digital Sky Survey and is currently head of participants in LAMOST U.S., a partnership allowing U.S. astronomers to take part in a survey of more than 7 million stars by the Large Sky Area Multi-Object Fiber Spectroscopic Telescope in China (LAMOST).
Credit: rpi.edu
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Posted: 12 Mar 2015 02:40 PM PDT
As telescopes of ever-greater power scan the cosmos looking for life, knowing where to look — and where not to waste time looking — will be of great value. New research by University of Washington astronomer Rory Barnes and co-authors describes possible planetary systems where a gravitational nudge from one planet with just the right orbital configuration and tilt could have a mild to devastating effect on the orbit and climate of another, possibly habitable world. Their findings have been accepted for publication in the Astrophysical Journal.
The magnitude of the chaos can range widely, Barnes said, from planets whose orbits remain largely circular to those “whose orbits get so elongated that a planet could slam into its host star — an extreme form of climate change!”
Even if the effect isn’t that dramatic, the orbit — thus the climate, as orbit is a primary driver of climate — could still be severe enough to inhibit life, or sterilize the planet if life has already begun, Barnes said.
The particular effect they studied is called a “mean motion resonance” and it comes into play when two planets’ orbital periods are an integer ratio of each other, such as Neptune orbiting the sun three times for every time Pluto orbits twice. A repetitive force, like a gravitational nudge, happens at the same place in the planets’ orbits around the star, the effect of which grows slowly over millions of years.
This can happen to a planet in its star’s habitable zone, the swath of space around it that’s just right to allow an orbiting rocky planet to have water in liquid form on its surface, thus giving life a chance. Barnes calls such worlds “chaotic Earths” and suggests making them lower priorities in the search for life.
Another condition for this orbital bullying is “mutual inclination,” meaning that the two planets are angled toward each other in space. Planets in our solar system all lie along the same plane in space, and are called coplanar, but not all planetary systems are like that. So Barnes and colleagues decided to “kick up” inclinations between planets in computer models and study the result.
“That was the basic idea,” he said. “What happens when you have planets that are in this resonance and with mutual inclinations?
“And what we found was that things go all haywire. Those little perturbations that keep happening at the same point cause one of the orbits to do some crazy things — even flip over entirely — and then kind of come back to where it was before. It was pretty unexpected for us.”
If the fluctuations are small, such worlds might yet retain their chance of life and be worth further study. But if they are dramatic, astronomers should probably look elsewhere.
“Planets in systems that drive orbits to near-misses with the host stars are less promising targets and should be skipped over for other candidates,” Barnes said, “even if they are found today on circular orbits in the habitable zone.”
Further computer modeling will help researchers distinguish between these two possibilities, he said.
Powerful tools such as the James Webb Space Telescope will come online in a few years, able to determine the atmospheres of exoplanets, or those outside the solar system. But the work will be expensive, so astronomers will need to choose their objects of study wisely, Barnes said.
Barnes is lead author of the study. Co-authors are Thomas Quinn and Russell Deitrick, UW astronomy professor and graduate student, respectively; Richard Greenberg of the University of Arizona and Sean Raymond of Laboratoire d’Astrophysique de Bordeaux in France.
The research was done through the Virtual Planetary Laboratory, a UW-based interdisciplinary research group, and funded by NASA and the National Science Foundation.
Credit: washington.edu
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Posted: 12 Mar 2015 02:10 PM PDT
Mark Watney, the hero featured in the best-selling book "The Martian" by Andy Weir, becomes marooned on Mars after his crewmates scramble to make an emergency departure following a dust storm tearing through their base. In his struggle for survival, Watney sets out to get to the landing site of "Mars Pathfinder," a robotic NASA spacecraft consisting of a lander and a rover that explored the surface of the red planet in 1997 in order to obtain a means of communicating with Earth. Using the HiRISE camera aboard NASA's Mars Reconnaissance Orbiter, which has been examining Mars with six instruments since 2006, the team acquired images of a large region on Mars called Acidalia Planitia, which includes the site where Watney's crew touched down in their spacecraft named Ares 3.
"Stranded astronaut Mark Watney spends most of his time at the Ares 3 landing site in southern Acidalia Planitia," said Alfred McEwen, a professor in the University of Arizona Lunar and Planetary Laboratory and principal investigator of the HiRISE mission. "The book describes Acidalia as flat and easy to drive over — he even drives (a rover) to the Pathfinder landing site and back."
However, as the HiRISE images revealed, this region of Mars is actually far more diverse, interesting and hazardous to drive over than depicted in the novel, according to McEwen.
Taken from an altitude of about 294 kilometers, or 182 miles, the image shows an area close to the Ares 3 landing site as shown in a map in the beginning of the novel. Many mounds are visible, including two large, crater- or volcano-like features that dominate the image. The mounds in the picture probably are ancient volcanoes, created by interactions between lava and water, or perhaps formed from the eruption of muddy sediments.
"We take images of this region because we want to get higher resolution of the region to better understand if these are indeed old volcanoes," said Ari Espinoza of the HiRISE mission team. "The image was acquired as a 'routine' image, not necessarily based on the book. However, the reason for our caption does come from the book. So, it's really just fortuitous: one of those 'Here’s the Hollywood version, but what does it really look like?' kind of things."
"Much of Acidalia Planitia is covered by dense fields of boulders up to several meters high that would be difficult to drive around," McEwen said. "There are also fissures associated with giant polygons, with steep rocky slopes that would be impassable. There are elongated fields of dense secondary craters where the surface is extremely rough at scales near the size of the rover."
When Watney travels into Arabia Terra, it is described as much rockier than Acidalia, but the opposite is generally true: Much of Arabia is dust-mantled and smooth at the scale of a rover.
"People commonly assume that 'smooth' at the large scales of kilometers means 'smooth' at small scales like meters to tens of meters," McEwen said. "We frequently see the opposite on Mars: Large, flat, low areas are more wind-scoured, removing fine materials and leaving rocks and eroded bedrock."
Credit: uanews.org
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