18.12.2022
NASA’s Perseverance Rover to Begin Building Martian Sample Depot
The 10 sample tubes being dropped on Mars’ surface so they can be studied on Earth in the future carry an amazing diversity of Red Planet geology.
In the coming days, NASA’s Perseverance rover is expected to begin building the first sample depot on another world. This will mark a crucial milestone in the NASA-ESA (European Space Agency) Mars Sample Return campaign, which aims to bring Mars samples to Earth for closer study.
The depot-building process starts when the rover drops one of its titanium sample tubes carrying a chalk-size core of rock from its belly 2.9 feet (88.8 centimeters) onto the ground at an area within Jezero Crater nicknamed “Three Forks.” Over the course of 30 or so days, Perseverance will deposit a total of 10 tubes that carry samples representing the diversity of the rock record in Jezero Crater.
NASA’s Perseverance Mars rover used its Mastcam-Z camera to capture this rocky hilltop nicknamed “Rockytop” on July 24, 2022, the 507th Martian day, or sol, of the mission.
Credit: NASA/JPL-Caltech/ASU/MSSS
The rover has been taking a pair of samples from each of its rock targets. Half of every pair will be deposited at Three Forks as a backup set, and the other half will remain inside Perseverance, which will be the primary means to convey the collected samples to the Mars launch vehicle as part of the campaign.
“The samples for this depot – and the duplicates held aboard Perseverance – are an incredible set representative of the area explored during the prime mission,” said Meenakshi Wadhwa, the Mars Sample Return program principal scientist from Arizona State University. “We not only have igneous and sedimentary rocks that record at least two and possibly four or even more distinct styles of aqueous alteration, but also regolith, atmosphere, and a witness tube.”
This map shows where NASA’s Perseverance Mars rover will be dropping 10 samples that a future mission could pick up. The orange circles represent areas where a Sample Recovery Helicopter could safely operate to acquire the sample tubes.
How to Build a Depot
One of the first requirements to build a sample depot on Mars is to find a level, rock-free stretch of terrain in Jezero Crater where there’s room for each tube to be deposited.
“Up to now, Mars missions required just one good landing zone; we need 11,” said Richard Cook, Mars Sample Return program manager at NASA’s Jet Propulsion Laboratory in Southern California. “The first one is for the Sample Retrieval Lander, but then we need 10 more in the vicinity for our Sample Recovery Helicopters to perform takeoffs and landings, and driving too.”
This short animation features key moments of NASA and ESA’s Mars Sample Return campaign, from landing on Mars and securing the sample tubes to launching them off the surface and ferrying them back to Earth.
After settling on a suitable site, the campaign’s next task was to figure out exactly where and how to deploy the tubes within that location. “You can’t simply drop them in a big pile because the recovery helicopters are designed to interact with only one tube at a time,” said Cook. The helicopters are intended to serve as a backup, just like the depot. To ensure a helicopter could retrieve samples without disturbing the rest of the depot or encountering any obstructions from the occasional rock or ripple, each tube-drop location will have an “area of operation” at least 18 feet (5.5 meters) in diameter. To that end, the tubes will be deposited on the surface in an intricate zigzag pattern, with each sample 16 to 49 feet (5 to 15 meters) apart from one another.
The depot’s success will depend on accurate placement of the tubes – a process that will take over a month. Before and after Perseverance drops each tube, mission controllers will review a multitude of images from the rover. This assessment will also give the Mars Sample Return team the precise data necessary to locate the tubes in the event of the samples becoming covered by dust or sand before they are collected.
Perseverance’s Extended Mission
Perseverance’s prime mission will conclude on Jan. 6, 2023 – one Mars year (about 687 Earth days) after its Feb. 18, 2021, landing.
“We will still be working the sample depot deployment when our extended mission begins on Jan. 7, so nothing changes from that perspective,” said Art Thompson, Perseverance’s project manager at JPL. “However, once the table is set at Three Forks, we’ll head to the top of the delta. The science team wants to take a good look around up there.”
Called the Delta Top Campaign, this new science phase will begin when Perseverance finishes its ascent of the delta’s steep embankment and arrives at the expanse that forms the upper surface of the Jezero delta, probably sometime in February. During this approximately eight-month campaign, the science team will be on the lookout for boulders and other materials that were carried from elsewhere on Mars and deposited by the ancient river that formed this delta.
“The Delta Top Campaign is our opportunity to get a glimpse at the geological process beyond the walls of Jezero Crater,” said JPL’s Katie Stack Morgan, deputy project scientist for Perseverance. “Billions of years ago a raging river carried debris and boulders from miles beyond the walls of Jezero. We are going to explore these ancient river deposits and obtain samples from their long-traveled boulders and rocks.”
More About the Mission
A key objective for Perseverance’s mission on Mars is astrobiology, including caching samples that may contain signs of ancient microbial life. The rover will characterize the planet’s geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith.
Subsequent NASA missions, in cooperation with ESA, would send spacecraft to Mars to collect these sealed samples from the surface and return them to Earth for in-depth analysis.
The Mars 2020 Perseverance mission is part of NASA’s Moon to Mars exploration approach, which includes Artemis missions to the Moon that will help prepare for human exploration of the Red Planet.
JPL, which is managed for NASA by Caltech, built and manages operations of the Perseverance rover.
Quelle: NASA
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Update: 23.12.2022
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NASA’s Perseverance Rover Deposits First Sample on Mars Surface
NASA’s Perseverance rover deposited the first of several samples onto the Martian surface on Dec. 21, 2022, the 653rd Martian day, or sol, of the mission.
Credit: NASA/JPL-Caltech/MSSS
Once the Perseverance team confirmed the first sample tube was on the surface, they positioned the WATSON camera located at the end of the rover’s robotic arm to peer beneath the rover, checking to be sure that the tube hadn’t rolled into the path of ... Credit: NASA/JPL-Caltech/MSSS
Filled with rock, the sample tube will be one of 10 forming a depot of tubes that could be considered for a journey to Earth by the Mars Sample Return campaign.
A titanium tube containing a rock sample is resting on the Red Planet’s surface after being placed there on Dec. 21 by NASA’s Perseverance Mars rover. Over the next two months, the rover will deposit a total of 10 tubes at the location, called “Three Forks,” building humanity’s first sample depot on another planet. The depot marks a historic early step in the Mars Sample Return campaign.
Perseverance has been taking duplicate samples from rock targets the mission selects. The rover currently has the other 17 samples(including one atmospheric sample) taken so far in its belly. Based on the architecture of the Mars Sample Return campaign, the rover would deliver samples to a future robotic lander. The lander would, in turn, use a robotic arm to place the samples in a containment capsule aboard a small rocket that would blast off to Mars orbit, where another spacecraft would capture the sample container and return it safely to Earth.
Engineers use OPTIMISM, a full-size replica of NASA’s Perseverance rover, to test how it will deposit its first sample tube on the Martian surface. The test was conducted in the Mars Yard at JPL.
The depot will serve as a backup if Perseverance can’t deliver its samples. In that case, a pair of Sample Recovery Helicopters would be called upon to finish the job.
The first sample to drop was a chalk-size core of igneous rockinformally named “Malay,” which was collected on Jan. 31, 2022, in a region of Mars’ Jezero Crater called “South Séítah.” Perseverance’s complex Sampling and Caching System took almost an hour to retrieve the metal tube from inside the rover’s belly, view it one last time with its internal CacheCam, and drop the sample roughly 3 feet (89 centimeters) onto a carefully selected patch of Martian surface.
Engineers react with surprise while testing how NASA’s Perseverance rover will deposit its sample tubes on the Martian surface. Less than 5% of the time, a flat end on the sample tube caused it to land straight up after dropping.
But the job wasn’t done for engineers at NASA’s Jet Propulsion Laboratory in Southern California, which built Perseverance and leads the mission. Once they confirmed the tube had dropped, the team positioned the WATSON camera located at the end of Perseverance’s 7-foot-long (2-meter-long) robotic arm to peer beneath the rover, checking to be sure that the tube hadn’t rolled into the path of the rover’s wheels.
They also wanted to ensure the tube hadn’t landed in such a way that it was standing on its end (each tube has a flat end piece called a “glove” to make it easier to be picked up by future missions). That occurred less than 5% of the time during testing with Perseverance’s Earthly twin in JPL’s Mars Yard. In case it does happen on Mars, the mission has written a series of commands for Perseverance to carefully knock the tube over with part of the turret at the end of its robotic arm.
This short animation features key moments of NASA and ESA’s Mars Sample Return campaign, from landing on Mars and securing the sample tubes to launching them off the surface and ferrying them back to Earth.
In coming weeks, they’ll have other opportunities to see whether Perseverance needs to use the technique as the rover deposits more samples at the Three Forks cache.
“Seeing our first sample on the ground is a great capstone to our prime mission period, which ends on Jan. 6,” said Rick Welch, Perseverance’s deputy project manager at JPL. “It’s a nice alignment that, just as we’re starting our cache, we’re also closing this first chapter of the mission.”
More About the Mission
A key objective for Perseverance’s mission on Mars is astrobiology, including the search for signs of ancient microbial life. The rover will characterize the planet’s geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith (broken rock and dust).
Subsequent NASA missions, in cooperation with ESA (European Space Agency), would send spacecraft to Mars to collect these sealed samples from the surface and return them to Earth for in-depth analysis.
The Mars 2020 Perseverance mission is part of NASA’s Moon to Mars exploration approach, which includes Artemis missions to the Moon that will help prepare for human exploration of the Red Planet.
JPL, which is managed for NASA by Caltech in Pasadena, California, built and manages operations of the Perseverance rover.
Quelle: NASA
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Ingenuity Mars helicopter tests new software on 37th Red Planet flight (video)
The little chopper traveled 203 feet (62 meters) on Dec. 17.
NASA's Ingenuity Mars helicopter flew for the 37th time on Saturday (Dec. 17), acing a hop designed in part to test the capabilities of its new software.
Ingenuity stayed aloft for 55 seconds and covered 203 feet (62 meters) of Red Planet ground on the flight, which was its third this month.
The main goals of Saturday's sortie were for Ingenuity "to reposition itself and test new flight software capabilities," officials with NASA's Jet Propulsion Laboratory (JPL) in Southern California, which manages Ingenuity's mission, said via Twitter(opens in new tab) on Monday (Dec. 19).
That new software, which was installed last month, allows Ingenuity to avoid hazards during landing and to use digital elevation maps for navigation purposes, mission team members have said(opens in new tab).
The rotorcraft landed on the floor of the Red Planet's Jezero Crater in February 2021 with NASA's Perseverance rover, which is hunting for signs of past Mars lifeand collecting samples for future return to Earth.
Ingenuity's primary mission was to show that aerial exploration is possible on Mars despite its thin atmosphere, which is just 1% as dense as that of Earth at sea level. The helicopter wrapped up that task over the course of five flights in the spring of 2021, then transitioned to an extended mission on which it's serving as a scout for Perseverance.
Ingenuity has now traveled a total of 24,867 feet (7,479 m) and stayed airborne for nearly 62 minutes during its 37 Red Planet flights, according to the mission's flight log(opens in new tab). Those numbers should continue to increase for a while, for the chopper remains in good health, team members have said.
Ingenuity's success is paving the way for future rotorcraft missions to the Red Planet. JPL is developing concepts for larger, more ambitious Mars helicopters that would gather science data, for example. And NASA plans to launch two Ingenuity-like craft to the Red Planet later in the 2020s to help bring Perseverance's samples home to Earth.
The baseline plan for the Mars sample-return campaign calls for Perseverance to deliver its samples to a rocket-equipped lander. That rocket will launch the samples to Mars orbit, where a European spacecraft will snag them and haul them to Earth, perhaps as early as 2033.
The helicopters will fly on the lander as a backup: If Perseverance isn't able to deliver the samples itself, the choppers will ferry them to the lander from depots on Jezero's floor. (Perseverance is taking two samples from each of its target rocks; it will store one set of samples on its body and cache the other set in depots.)
Quelle: SC
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Update: 26.12.2022
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Perseverance rover drops 2nd sample tube on Mars, its biggest early Christmas present yet for 2033
The sample tube contained the longest Mars rock sample collected by the Perseverance rover yet.
This photo from NASA's Mars rover Perseverance shows its second sample tube on the Martian surface, in the rover's shadow. NASA announced it was deposited on Dec. 23, 2022. (Image credit: NASA/JPL-Caltech)
NASA's Perseverance rover keeps dropping early Christmas presents on Mars.
On Friday (Dec. 23), NASA announced that Perseverance successfully dropped its second rock sample tube on the Martian surface. And while it's not the first Marssample Perseverance has dropped for a potential future mission to bring to Earth in 2033, it certainly is the biggest.
"My second sample drop is looking good!" NASA's Perseverance rover team wrote in a Twitter update(opens in new tab) Friday. "This tube holds a piece of sedimentary rock from the edge of the ancient river delta here — the longest rock core I've taken to date."
The longest rock core collected by Perseverance is a sample called "Mageik," which the rover drilled out of the rock "Amalik" this fall from the "Enchanted Lake" region of ancient delta in its Jezero Crater landing site.
"The tube itself is about the size of a marker, and I measured the rock core sample inside at 7.36 cm (about 2.9 inches)," NASA wrote as Perseverance on Twitter(opens in new tab). Perseverance dropped its first sample tube at a nearby spot on Wednesday (Dec. 21).
Perseverance is dropping 10 sealed tubes containing Mars rock samples, which resemble miniature lightsabers from Star Wars, for potential collection by a future Mars Sample Return mission. That mission and an orbiter could launch to Mars by 2028 and return the sample tubes to Earth five years later. If all goes according to plan, Perseverance or two small helicopters will deliver Mars samples to a lander that would then launch them into space so that a waiting orbiter can collect them for the trip back to Earth.
This map shows where NASA’s Perseverance Mars rover is taking to drop 10 samples that a future mission could pick up. The orange circles represent areas where a Sample Recovery Helicopter could safely operate to acquire the sample tubes. (Image credit: NASA/JPL-Caltech
The samples Perseverance is dropping are backups. The rover collected twin samples at each drill site, storing one inside its body while dropping the other in case a backup is needed. Perseverance is expected to deliver the ones it carries to the waiting lander if the nuclear-powered lasts long enough to reach the Mars Sample Return lander at the end of the decade.
NASA's Perseverance rover landed on Mars in February 2021. It's primary mission will last two years, but NASA hopes the rover could live much longer. Its predecessor, the nuclear-powered Curiosity rover, recently celebrated its 10th anniversary on Mars in August.
Quelle: SC
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Update: 29.12.2022
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MOXIE sets consecutive personal bests and Mars records for oxygen
production
MOXIE gathers information about Mars and ISRU technology by proving itself in unique Martian weather conditions. The atmosphere around Jezero Crater, the present location of Perseverance, reached peak density for the year mid (Earth) summer. This presented the perfect opportunity for the MOXIE science team to step on the accelerator and test how fast we could safely produce oxygen.
Perseverance has a unique device near its heart that inhales Mars' atmosphere and exhales pure oxygen. This device is named MOXIE, the Mars Oxygen In Situ Resource Utilization Experiment.
The toaster-sized MOXIE uses a high-temperature, electrochemical process called solid oxide electrolysis to strip oxygen ions from the carbon dioxide in the atmosphere of Mars. There are two little gas exit ports on MOXIE: one where oxygen flows out and another where a mixture of carbon monoxide and unreacted carbon dioxide exit.
MOXIE is significant as the first demonstration on another planet of In Situ Resource Utilization (ISRU), a group of technologies that enable extraterrestrial "living off the land." Many people initially assume that this means that MOXIE's primary purpose is to produce oxygen for future astronauts to breathe.
While this is certainly an application, the most significant use of MOXIE's technological descendants will be to produce oxygen for use as an oxidizer in rockets created to return explorers back to Earth after a successful Mars mission.
MOXIE gathers information about Mars and ISRU technology by proving itself in unique Martian weather conditions. The atmosphere around Jezero Crater, the present location of Perseverance, reached peak density for the year mid (Earth) summer. This presented the perfect opportunity for the MOXIE science team to step on the accelerator and test how fast we could safely produce oxygen.
This test occurred on Sol 534 (Aug. 22, 2022) and produced a peak of 10.44 grams per hour of oxygen. This represented a new record for Martian oxygen production! The team was thrilled to surpass our design goal of 6 grams per hour by over 4.4 grams. The peak rate was held for 1 minute of the 70 minutes oxygen was produced during the run.
MOXIE's next opportunity to operate came recently. Despite the decreasing density of the Mars atmosphere, on Sol 630 (Nov. 28, 2022) MOXIE managed to break the record again and produce nearly 10.56 grams per hour at peak.
Oxygen production was sustained for a 9.79 grams per hour for nearly 40 minutes. These numbers may seem small, but MOXIE production runs are limited by available rover power. In addition, MOXIE technology was miniaturized to accommodate the limited space available on the rover. A MOXIE for a human Mars mission would produce oxygen nearly 200 times faster and work continuously for well over a year.
Each person who brought MOXIE to life, as well as future Mars astronauts, have a lot to celebrate about this milestone. Utilizing space resources will make space exploration sustainable and is key to opening new frontiers of discovery for humanity.
Eight years have passed since I began working on MOXIE as a graduate student at MIT. Over that time, I have grown with the project and dedicated my career to discovering and utilizing space resources. I've taken this moment to rejoice and reflect on the perseverance required to create foundational technologies for our next leap into the cosmos.
Quelle: SD
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Update: 15.01.2023
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Mars rover Perseverance spots Ingenuity helicopter resting on sand dune (photo)
The two robots are close together again.
Zoomed-in view of a photo of NASA's Ingenuity Mars helicopter taken by the agency's Perseverance rover. The rover team posted this image on Twitter on Jan. 11, 2023. (Image credit: NASA/JPL-Caltech)
NASA's Perseverance rover just caught another glimpse of its pioneering robotic cousin.
The car-sized Perseverance snapped a photo recently of the Ingenuity helicopter as the 4-pound (1.8 kilograms) rotorcraft sat atop a Red Planet sand dune.
"The #MarsHelicopter and I are closer together than we've been in a while, and guess who I spotted resting on a dune between flights. Can you believe Ingenuity is gearing up for Flight #39?" the Perseverance team said via Twitter(opens in new tab) on Wednesday (Jan. 11), in a post that featured a photo of the little chopper.
Ingenuity and Perseverance landed together inside Mars' Jezero Crater in February 2021. The 28-mile-wide (45 kilometers) Jezero hosted a big lake and a river delta long ago, and Perseverance is scouring the area for signs of ancient life on Mars.
The six-wheeled robot is also collecting and caching dozens of samples for future return to Earth. For the past few weeks, Perseverance has been caching some of its sample tubes in a "depot" in a patch of Jezero's floor that the mission team calls Three Forks.
Perseverance has so far deposited six of a planned 10 sample tubes(opens in new tab) in the Three Forks depot, which serves as a backup in case the rover isn't healthy enough to haul material to a future NASA lander later this decade. A rocket aboard that lander will launch the samples to Mars orbit, where they'll be picked up by a European spacecraft and hauled back to Earth. The samples could land here as early as 2033.
The depot samples are doubles; Perseverance is keeping a set of material drilled from the same target rocks on its body. If need be, two Ingenuity-like helicopters that will launch with the future lander will fly over to Three Forks and grab the sample tubes there one by one.
Ingenuity is currently serving as a scout for Perseverance, helping the rover team pick the best routes through the rough Jezero landscape and identify promising outcrops for in-depth study.
This work is part of the chopper's extended mission. Not long after landing, Ingenuity aced its primary five-flight campaign, showing that powered flight is possible in the thin Martian atmosphere.
Ingenuity conducted its 39th Martian flight on Wednesday, covering 459 feet (140 meters) of ground over the course of nearly 79 seconds. To date, the chopper has flown a total of 25,690 feet (7,830 m) on Mars and stayed airborne for more than 64 minutes, according to the mission's flight log(opens in new tab).
Perseverance has captured footage of Ingenuity before. The rover snapped photos of the chopper just after it deployed onto Jezero's floor, for example, and also recorded video of Ingenuity's 13th flight, which took place in September 2021.
Quelle: SC
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Update: 22.01.2023
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Mars helicopter Ingenuity aces 40th Red Planet flight
The sortie on Thursday (Jan. 19) covered about 584 feet (178 meters).
NASA's Ingenuity Mars helicopter captured this image with its navigation camera on Jan. 19, 2023, during its 40th Red Planet flight. (Image credit: NASA/JPL-Caltech)
NASA's tiny Ingenuity helicopter now has 40 off-Earth flights under its belt.
The 4-pound (1.8 kilograms) Ingenuity lifted off yet again on Thursday (Jan. 19), staying aloft for nearly 92 seconds on a sortie that covered about 584 feet (178 meters) of horizontal distance.
The flight repositioned Ingenuity, moving it from "Airfield Z" on the floor of Mars' Jezero Crater to "Airfield Beta," according to the mission's flight log(opens in new tab). That journey took the little chopper over some sand dunes, as imagery captured during the hop shows.
Zoomed-in view of a photo of NASA's Ingenuity Mars helicopter taken by the agency's Perseverance rover. The rover team posted this image on Twitter on Jan. 11, 2023. (Image credit: NASA/JPL-Caltech
Ingenuity landed with NASA's car-sized Perseverance Mars rover in February 2021 inside the 28-mile-wide (45 kilometers) Jezero, which hosted a big lake and a river delta billions of years ago.
Perseverance is searching for signs of past Mars life in the area and collecting dozens of samples that will be returned to Earth as early as 2033 by a joint NASA/European Space Agency campaign.
The plan calls for Perseverance to deliver those samples to a rocket-equipped NASA lander, which will launch the material to Mars orbit. Up there, the sample container will be grabbed by a European probe, which will haul it to Earth. These other spacecraft are scheduled to launch in the mid- to late 2020s.
Over the past few weeks, Perseverance has been dropping sample tubes in a "depot" on Jezero's floor. The depot is a backup, in case the rover isn't healthy enough to deliver the samples to the lander later this decade. In that scenario, two small, Ingenuity-like helicopters that launched aboard the lander will collect the depot tubes one by one.
To date, Perseverance has cached eight of a planned 10 sample tubes(opens in new tab) in the depot, which is in a patch of Jezero's floor the mission team calls Three Forks.
Ingenuity is a technology demonstrator designed to show that aerial exploration is possible on Mars despite the planet's thin atmosphere. The helicopter's prime mission covered just five flights, which Ingenuity knocked out shortly after touching down inside Jezero.
The chopper then shifted into an extended mission, during which it has been pushing its flight capabilities and serving as a scout for Perseverance. The helicopter's aerial observations help the rover team identify potentially interesting scientific targets and pick the best routes through the rugged landscapes on Jezero's floor.
Quelle: SC
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Update: 27.01.2023
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Perseverance Mars rover files 1st detailed weather report
The average temperature at Jezero Crater is a chilly minus 67 degrees Fahrenheit (minus 55 degrees Celsius).
Mars' weather is proving to be turbulent and diverse over the Perseverance rover's landing site in Jezero Crater.
NASA's Perseverance rover is dotted with various weather sensors, collectively called the Mars Environmental Dynamics Analyzer (MEDA), which cover the rover's neck and deck; some are also housed in its interior. Scientists have now released MEDA's weather report for the project's first 250 sols (Martian days, which are each about 40 minutes longer than an Earth day), and the findings describe a surprisingly dynamic atmosphere near the Red Planet's surface.
MEDA, which was built by Spanish scientists led by José Antonio Rodríguez-Manfredi of the Centre for Astrobiology in Madrid, includes five button-sized sensors that routinely measure the Martian air temperature at four different altitudes to create a vertical temperature profile; two wind-speed sensors; and additional sensors to measure radiation, dust, humidity and air pressure.
Spanning the Red Planet's northern hemisphere spring into early summer, the results focus on the "atmospheric surface layer (ASL)" — the lower layer of Mars' atmosphere that is in contact with the planet's surface. Heat and mass in the form of dust are exchanged between the surface and the ASL, with each region affecting the other.
Perseverance measured the average air temperature at Jezero to be minus 67 degrees Fahrenheit (minus 55 degrees Celsius), but this can vary by as much as 90 to 110 degrees F (50 to 60 degrees C), particularly between day and night. Air pressure also fluctuated, both daily and more noticeably on a seasonal basis as the carbon dioxide frost at the poles sublimated in the early summer "heat," bolstering the thin atmosphere.
"The pressure and temperature of Mars' atmosphere oscillate with periods of the Martian solar day … following the daily cycle of sunshine greatly influenced by the amount of dust and the presence of clouds in the atmosphere," a co-author of the report, Agustín Sánchez-Lavega of the Planetary Sciences Group at the University of the Basque Country in Spain, said in a statement.
As the daytime sun warms the surface and lower atmosphere, pockets of air begin to rise, creating gentle turbulence that leads to some of the observed temperature fluctuations. The turbulence stops in the evening as the sun sinks down toward the horizon and solar heating drops off, allowing the air to settle, at least for a short time.
Then, Perseverance often measured instability returning to the ASL at the equivalent of about 2 a.m. local time on Mars. Similar returning instability was also witnessed by NASA's InSight lander, which ended its mission in December after four years on the Red Planet. MEDA has now confirmed that this is the result of the warm surface of the local terrain, enhanced by winds with gentle speeds to 6.5 to 13 feet (2 to 4 meters) per second driven by differences in the temperature of the surface.
Speaking of the wind, MEDA measured a daily wind cycle, with strong south-easterly gusts of 82 feet (25 m) per second around midday, weaker winds of 23 feet (7 m) per second in the afternoon, a wind-direction reversal at night, and no winds at all between 4 a.m. and 6 a.m. local time.
Previous findings have shown how Perseverance has detected dust devils passing over the rover and the accompanying change in air pressure.
"The dust devils are more abundant at Jezero than elsewhere on Mars, and can be very large, forming whirlwinds more than 100 meters [330 feet] in diameter," Ricardo Hueso, also of the Planetary Sciences Group at the University of the Basque Country, said in the statement. "With MEDA we have been able to characterize not only their general aspects [their size and abundance] but also to unravel how these whirlwinds function."
Understanding Mars' present-day atmosphere is important not just because of scientific curiosity. It can also affect missions landing on the planet. In addition, the 10 sample canisters left on the ground by Perseverance as it trundles around Jezero Crater will be constantly exposed to the atmospheric conditions for many years; the future mission meant to retrieve them is currently scheduled to land on the Red Planet in 2031.
The findings were published on Jan. 9 in the journal Nature Geoscience(opens in new tab).
Quelle: SC