Scientist Study

Your source for the latest science & space news

Thursday, 23 September 2021

Court filings shed light on Blue Origin vs. SpaceX lunar lander fight, with dark spots


Redacted versions of documents relating to Blue Origin’s federal lawsuit against the federal government and SpaceX lay out further details about the dispute over a multibillion-dollar NASA lunar lander contract, but the details that are left out are arguably just as intriguing.

Today the U.S. Court of Federal Appeals released the 59-page text of the Blue Origin-led industry consortium’s complaint, which was filed in August. The court also shared redacted responses from SpaceX.

The filings focus on NASA’s April decision to award SpaceX a $2.9 billion contract to develop its Starship super-rocket as the landing system for the Artemis program’s first crewed trip to the lunar surface, planned for as early as 2024.

At the time, NASA said that SpaceX’s proposal was technically superior to the concepts offered by Blue Origin and its partners — Lockheed Martin, Northrop Grumman and Draper — and by another competitor, Dynetics. SpaceX had the low bid, with Blue Origin’s team proposing $5.9 billion for its landing system. Draper’s proposal was even more expensive.

The original hope was that NASA might make multiple awards, in the interest of promoting competition and having a Plan B. But space agency officials said Congress appropriated only enough money to make one award.

In a protest filed with the Government Accountability Office, Blue Origin complained that NASA didn’t evaluate the proposals properly, and that SpaceX was given a chance to restructure its bid to fit NASA’s budget. The GAO largely sided with NASA and SpaceX in a ruling that let the contract award stand, but then Blue Origin took the dispute to federal court.

Blue Origin’s lawsuit touches on the aforementioned talking points, but it primarily focuses on waivers that NASA issued relating to “supporting spacecraft” that are apparently used in connection with SpaceX’s landing system. The details about those supporting spacecraft were blacked out by the court.

The lawsuit argues that issuing the waivers for individual flight readiness reviews and “other review requirements” for the supporting spacecraft gave SpaceX an unfair advantage in the competition. “Blue Origin and Dynetics did not get such a chance to compete with waived requirements the Agency afforded to SpaceX,” it says. “Had it had such an opportunity, Blue Origin would have been able to propose a substantially lower price…”

So what is the supporting spacecraft? References to SpaceX’s moon-landing Starship and a tanker version of the same spacecraft that would be used for in-flight refueling were left unredacted — so those probably aren’t at issue. The redacted document makes no mention of SpaceX’s Super Heavy booster, but guessing whether that’s the sticking point would be pure speculation.

Blue Origin calls on the court to issue an order that would suspend SpaceX’s work on the lunar lander contract and give the competitors an equal chance to discuss their proposals with NASA. If the order is issued as proposed by Blue Origin, the competitors would send “final proposal revisions” to NASA, and space agency officials would make a new award determination.

In one of its responses to the complaint, SpaceX says Blue Origin is relying on a “flawed interpretation” of NASA’s solicitation — an interpretation that was “unfortunately adopted by GAO” in its ruling.

SpaceX also says the unredacted version of Blue Origin’s complaint should remain sealed because it would disclose SpaceX’s proprietary and confidential information. The judge in the case, Richard Hertling, agreed with SpaceX on the redaction issue.

The court is expected to hear oral arguments in October, with an eye toward issuing a ruling by early November. In the meantime, NASA has granted a total of $146 million in fixed-price awards to Blue Origin, SpaceX, Dynetics, Lockheed Martin and Northrop Grumman through a follow-up program aimed at boosting the space agency’s lunar landing capabilities.

Source: Link

Those Cracks Found on The ISS Are Likely 'Serious', Says Former NASA Astronaut


Cracks are appearing on the International Space Station (ISS), and retired NASA astronaut Bill Shepherd says they're a "fairly serious issue."

After Russian cosmonauts spotted the cracks on the station's Zarya module, Vladimir Solovyov, flight director of the Russian segment of the ISS, publicly revealed the discovery in August.

The cracks don't pose a danger to astronauts at this time, NASA says, and the agency told Insider last month that nobody had identified "new potential leak sites" on the station.

But in a House committee hearing on Tuesday, Shepherd told Congressional representatives that "there are probably other cracks we haven't found yet."

"As far as I know, the Russian engineers and the NASA engineers – they've analyzed it – they don't exactly understand why these cracks are appearing now," Shepherd said.

Shepherd has flown to orbit four times on the Space Shuttles. He worked on the International Space Station Program when its first modules were launching, and he commanded the first crew to the station in 2000. He said at the hearing that he'd learned more about the cracks in two meetings of NASA's ISS Advisory Committee, which he recently joined.

The cracks are "quite small – they look like scratches on the surface of the aluminum plate," Shepherd said, adding, "there are probably something like half a dozen of them."

NASA did not immediately respond to a request for comment.

'This is bad'

Shepherd told the House committee that currently, the cracks are not long enough to pose a "serious problem."

But last month, Solovyov told state-owned news agency RIA: "This is bad and suggests that the fissures will begin to spread over time," according to a Reuters report translating his statement.

Solovyov did not share how extensive the cracks were at the time.

Shepherd didn't say whether NASA and Russia plan to further investigate the cracks beyond the analysis they already finished.

In the past, both space agencies have taken their time when investigating and repairing issues that don't threaten the safety of astronauts or interfere with ISS operations.

The space station is getting old

The ISS has been orbiting Earth for 20 years, and it's showing signs of age. Russia's side of the space station hosts some of its oldest components, and the cracks are the latest in a series of issues in those modules.

Last year, a toilet on the segment went bust, temperatures mysteriously increased, and an oxygen-supply system broke down.

In September 2019, another space-station module, Zvezda, which provides living quarters for the cosmonauts, started leaking air. That wasn't an immediate danger to astronauts, and they eventually found the hole and patched it with Kapton tape.

Russian media previously reported that Solovyov told the Russian Academy of Sciences: "There are already a number of elements that have been seriously damaged and are out of service. Many of them are not replaceable. After 2025, we predict an avalanche-like failure of numerous elements onboard the ISS."

Even Russia's newest module – a spacecraft called Nauka, which it launched to the ISS in July – has experienced serious problems. Shortly after it docked to the station, Nauka began unexpectedly firing its thrusters. This caused the entire ISS to spin around 540 degrees and flip upside down before flight controllers regained control an hour later.

NASA has the funds to keep operating the ISS through 2024, and it's aiming to get an extension from Congress to continue the station's activities through 2028.

But Shepherd said that NASA should first solve the mystery of the Zarya module's new cracks.

"Getting to the bottom of this is a fairly serious issue," Shepherd said. "I don't think the station's in any immediate danger. But before we clear the station for another so many years of operational use, we should better understand this."

The ISS will eventually be retired and push itself into the atmosphere to burn up. After that, NASA doesn't want to build a new station; the agency is recruiting private companies to do that instead.

It's currently evaluating about a dozen space-station proposals from various companies, with the aim of distributing $400 million among two to four of them.

Eventually, NASA hopes to be one of many customers on private commercial space stations.

The agency has already awarded Axiom Space $140 million to fly modules up to the ISS that will eventually detach from it to become their own space station. Axiom aims to launch its first module to the ISS in 2024.

China, meanwhile, launched the first piece of its own space station earlier this year, and astronauts completed their first three-month mission there last week.

Source: Link

Space Station Crew to Relocate Soyuz, Make Room for New Crewmates


Three residents of the International Space Station will take a short ride aboard a Soyuz MS-18 spacecraft Tuesday, Sept. 28, relocating the spacecraft to prepare for the arrival of the next set of station crew members.

Expedition 65 flight engineers Mark Vande Hei of NASA and Oleg Novitskiy and Pyotr Dubrov of the Russian Space Agency Roscosmos will undock from the station’s Earth-facing Rassvet module at 8:21 a.m. EDT. They will dock again at the Nauka Multipurpose Laboratory Module at 9 a.m. This will be the first time a spacecraft has attached to the new Nauka module, which arrived at the station in July.

Live coverage of the maneuver will begin at 8 a.m. on NASA Television, the NASA app, and the agency’s website.

The relocation will free the Rassvet port for the docking of another Soyuz spacecraft, designated Soyuz MS-19, which will carry three Russian crew members to the station in October. Soyuz commander and cosmonaut Anton Shkaplerov of Roscosmos and spaceflight participants Klim Shipenko and Yulia Peresild are scheduled to launch to the station Tuesday, Oct. 5, from the Baikonur Cosmodrome in Kazakhstan.

This will be the 20th Soyuz port relocation in station history and the first since March 2021.

Vande Hei and Dubrov are scheduled to remain aboard the station until March 2022. At the time of his return, Vande Hei will have set the record for the longest single spaceflight for an American. Novitskiy, Shipenko, and Peresild are scheduled to return to Earth in October aboard the Soyuz MS-18 spacecraft.

For more than 20 years, humans have lived and worked continuously aboard the International Space Station, advancing scientific knowledge and demonstrating new technologies, making research breakthroughs not possible on Earth. As a global endeavor, 244 people from 19 countries have visited the unique microgravity laboratory that has hosted more than 3,000 research and educational investigations from researchers in 108 countries and areas.

Source: Link

SpaceX satellite signals used like GPS to pinpoint location on Earth


Engineering researchers have developed a method to use signals broadcast by Starlink internet service satellites to accurately locate a position here on Earth, much like GPS does. It is the first time the Starlink system has been harnessed by researchers outside SpaceX for navigation.

The Starlink satellites, sent into orbit by Elon Musk’s SpaceX, are designed to provide broadband internet connections in remote locations around the world. The researchers used signals from six Starlink satellites to pinpoint a location on Earth within 8 meters of accuracy.

Their findings, shared today (Sept. 22, 2021) at the Institute of Navigation GNSS annual meeting in St. Louis, may provide a promising alternative to GPS. Their results will be published in the upcoming issue of the journal IEEE Transactions on Aerospace and Electronic Systems.

The researchers did not need assistance from SpaceX to use the satellite signals, and they emphasized that they had no access to the actual data being sent through the satellites – only to information related to the satellite’s location and movement.

“We eavesdropped on the signal, and then we designed sophisticated algorithms to pinpoint our location, and we showed that it works with great accuracy,” said Zak Kassas, director of the Center for Automated Vehicles Research with Multimodal Assured Navigation (CARMEN), a multi-institution transportation center housed at The Ohio State University.

“And even though Starlink wasn’t designed for navigation purposes, we showed that it was possible to learn parts of the system well enough to use it for navigation.”

CARMEN is one of four recently awarded U.S. Department of Transportation University Transportation Centers. Kassas is an adjunct professor of electrical and computer engineering at Ohio State and an associate professor at the University of California, Irvine.

For this research, Kassas and his research team studied the Starlink system and analyzed signals being sent by the satellites. They developed an algorithm that could use the signals of multiple satellites to locate a position on Earth. Then, they set up an antenna on the campus of UCI and tried to use the network to pinpoint the antenna’s location.

Using Starlink, they identified the antenna’s location within about 7.7 meters. GPS, by comparison, generally identifies a device’s location within 0.3 and 5 meters. The team has used similar techniques with other low Earth orbit satellite constellations, but with less accuracy, pinpointing locations within about 23 meters, Kassas said. The team has also been working with the U.S. Air Force to pinpoint locations of high-altitude aircraft; they were able to come within 5 meters using land-based cellular signals, Kassas said.

SpaceX has some 1,700 satellites in Earth’s low orbit, meaning they circle the planet about 1,200 km from Earth’s surface. SpaceX ultimately plans to launch more than 40,000 satellites.

Kassas said as the Starlink constellation grows, so, too, will the accuracy of his team’s navigation and geo-location technique with its signals.

Their discovery could allow the government or other agencies to use Starlink’s satellites as an alternative navigation system – and possibly, a more secure one – to GPS, which powers almost all navigation systems around the world, Kassas said.

GPS has been in place for more than 30 years and its signals are well-known, akin to open-source software, Kassas said. That is an asset to companies that develop GPS receivers in smartphones, wearable fitness devices and vehicles, but it also makes the system vulnerable to attacks. GPS satellites are also farther away from Earth than low-Earth orbiting systems, making their signals weaker, and therefore more susceptible to interference.

Jamming attacks on GPS signals can take down GPS signals altogether, which has been a growing problem for aviation. Spoofing attacks on GPS can manipulate where a given vehicle appears in systems designed to monitor locations and prevent vehicles from overlapping routes; attacks can also take over a vehicle’s path – for example, some attacks have overtaken military and civilian drones, maritime vessels, and even Tesla’s autopilot.

The Starlink system is appealing to navigation experts, Kassas said, because the signals, until now, have been private – SpaceX has not shared them with governments or researchers. Starlink satellites are closer to Earth than GPS satellites are, making their signals much stronger and less susceptible to interference.

“The important catch here is that we are not ‘listening’ in on what is being sent over these satellites,” Kassas said. “We learned the signals just well enough to harness them for navigation purposes.”

Co-authors on the research were Joe Khalife and Mohammad Neinavaie of the University of California, Irivine.

This work was funded by the U.S. Office of Naval Research, the U.S. Department of Transportation and the National Science Foundation.

Source: Link

NASA’s James Webb Space Telescope to Explore Forming Planetary Systems


Planetary systems take millions of years to form, which introduces quite a challenge for astronomers. How do you identify which stage they are in, or categorize them? The best approach is to look at lots of examples and keep adding to the data we have—and NASA's upcoming James Webb Space Telescope will be able to provide an infrared inventory. Researchers using Webb will observe 17 actively forming planetary systems. These particular systems were previously surveyed by the Atacama Large Millimeter/submillimeter Array (ALMA), the largest radio telescope in the world, for the Disk Substructures at High Angular Resolution Project (DSHARP).

Webb will measure spectra that can reveal molecules in the inner regions of these protoplanetary disks, complementing the details ALMA has provided about the disks' outer regions. These inner regions are where rocky, Earth-like planets can start to form, which is one reason why we want to know more about which molecules exist there.

A research team led by Colette Salyk of Vassar College in Poughkeepsie, New York, and Klaus Pontoppidan of the Space Telescope Science Institute in Baltimore, Maryland, seek the details found in infrared light. "Once you switch to infrared light, specifically to Webb's range in mid-infrared light, we will be sensitive to the most abundant molecules that carry common elements," explained Pontoppidan.

Researchers will be able to assess the quantities of water, carbon monoxide, carbon dioxide, methane, and ammonia—among many other molecules—in each disk. Critically, they will be able to count the molecules that contain elements essential to life as we know it, including oxygen, carbon, and nitrogen. How? With spectroscopy: Webb will capture all the light emitted at the center of each protoplanetary disk as a spectrum, which produces a detailed pattern of colors based on the wavelengths of light emitted. Since every molecule imprints a unique pattern on the spectrum, researchers can identify which molecules are there and build inventories of the contents within each protoplanetary disk. The strength of these patterns also carries information about the temperature and quantity of each molecule.

"Webb's data will also help us identify where the molecules are within the overall system," Salyk said. "If they're hot, that implies they are closer to the star. If they're cooler, they may be farther away." This spatial information will help inform models that scientists build as they continue examining this program's data.

Knowing what's in the inner regions of the disks has other benefits as well. Has water, for example, made it to this area, where habitable planets may be forming? "One of the things that's really amazing about planets—change the chemistry just a little bit and you can get these dramatically different worlds," Salyk continued. "That's why we're interested in the chemistry. We're trying to figure out how the materials initially found in a system may end up as different types of planets."

If this sounds like a significant undertaking, do not worry—it will be a community effort. This is a Webb Treasury Program, which means that the data is released as soon as it's taken to all astronomers, allowing everyone to immediately pull the data, begin assessing what's what in each disk, and share their findings.

"Webb's infrared data will be intensively studied," added co-investigator Ke Zhang of the University of Wisconsin–Madison. "We want the whole research community to be able to approach the data from different angles."

Why the up-close examination?

Let's step back, to see the forest for the trees. Imagine you are on a research boat off the coast of a distant terrain. This is the broadest view. If you were to land and disembark, you could begin counting how many trees there are and how many of each tree species. You could start identifying specific insects and birds and match up the sounds you heard offshore to the calls you hear under the treetops. This detailed cataloging is very similar to what Webb will empower researchers to do—but swap trees and animals for chemical elements.

The protoplanetary disks in this program are very bright and relatively close to Earth, making them excellent targets to study. It's why they were surveyed by ALMA. It's also why researchers studied them with NASA's Spitzer Space Telescope. These objects have only been studied in depth since 2003, making this a relatively newer field of research. There's a lot Webb can add to what we know.

The telescope's Mid-Infrared Instrument (MIRI) provides many advantages. Webb's location in space means that it can capture the full range of mid-infrared light (Earth's atmosphere filters it out). Plus, its data will have high resolution, which will reveal many more lines and wiggles in the spectra that the researchers can use to tease out specific molecules.

The researchers were also selective about the types of stars chosen for these observations. This sample includes stars that are about half the mass of the Sun to about twice the mass of the Sun. Why? The goal is to help researchers learn more about systems that may be like our own as it formed. "With this sample, we can start to determine if there are any common features between the disks' properties and their inner chemistry," Zhang continued. "Eventually, we want to be able to predict which types of systems are more likely to generate habitable planets."

Beginning to answer big questions

This program may also help researchers begin to answer some classic questions: Are the forms taken by some of the most abundant elements found in protoplanetary disks, like carbon, nitrogen, and oxygen, "inherited" from the interstellar clouds that formed them? Or does the precise mix of chemicals change over time? "We think we can get to some of those answers by making inventories with Webb," Pontoppidan explained. "It's obviously a tremendous amount of work to do—and cannot be done only with these data—but I think we are going to make some major progress."

Thinking even more broadly about the incredibly rich spectra Webb will provide, Salyk added, "I'm hoping that we'll see things that surprise us and then begin to study those serendipitous discoveries."

This research will be conducted as part of Webb General Observer (GO) programs, which are competitively selected using a dual-anonymous review system, the same system that is used to allocate time on the Hubble Space Telescope.

Source: Link

Wednesday, 22 September 2021

A new way to control qubits


A research team that includes two UO physicists have outlined new techniques for controlling the building blocks of quantum computing, a potentially significant step toward making such computers more accurate and useful.

Physicists David Allcock and David Wineland are founders of the new Oregon Ions Laboratory, which was recently set up in the basement of Willamette Hall. They are among 12 authors of a new paper, which is based on an experiment at the National Institute for Standards and Technology in Boulder, Colorado. Both scientists previously worked at the Colorado lab and continued to collaborate on the project after coming to the UO in 2018.

The techniques, described in the journal Nature, involve the use of trapped-ion quantum bits, or qubits, in quantum computing and simulations. They could lead to improvements in the operation of quantum computers, which still make too many computation errors to be effective tools, the physicists said.

The problem with quantum computers is that their logic gates—the tools used to perform basic logic functions in computing—"are really bad," Allcock said.

"They fail about 1 percent of the time," he said. "You can do about 100 (operations), then you get garbage out."

Wineland added, "The whole field is in a stage now, because of errors that exist, that we can't do lengthy calculations or simulations of practical value on our machines."

The goal is to get to 10,000 operations without error and then add layers of checks to fix the errors as they happen, he said.

"We want to get to that point," Allcock said. "Then you can use quantum computers for something useful. Right now they're just toys."

Wineland said trapped ions are like a bowl of marbles that have certain magnetic properties. Physicists can apply forces to the ions with different methods, including lasers, Allcock said. But lasers are expensive and complex machines, whereas making logic gates using magnetic forces is cheaper and more practical because they can be generated directly with integrated circuits, he said.

"What we did here is show these techniques work as well as anyone has done logic gates before," he said.

Google and IBM are among the commercial enterprises that have armies of engineers working on such problems, while academic physicists are trying to show there are better, more basic techniques for solving them.

"We've shown you can do it in a technically simpler way," he said.

If physicists and engineers can make quantum computers reliable and able to operate with large enough capacity, they could simulate other systems, Wineland said. For example, a quantum computer could simulate the action of a molecule used in drug therapy without having to synthesize it in a lab.

"There are some very practical, useful outcomes," Wineland said. "We're just scratching the surface."

Reference: 

Srinivas, R. et al. High-fidelity laser-free universal control of trapped ion qubits. Nature (2021). DOI: 10.1038/s41586-021-03809-4

Astronomers Have Discovered a Gigantic Sphere-Shaped Cavity in Space


Gigantic cavity in space sheds new light on how stars form.

Astronomers analyzing 3D maps of the shapes and sizes of nearby molecular clouds have discovered a gigantic cavity in space.

The sphere-shaped void, described today in the Astrophysical Journal Letters, spans about 150 parsecs — nearly 500 light years — and is located on the sky among the constellations Perseus and Taurus. The research team, which is based at the Center for Astrophysics | Harvard & Smithsonian, believes the cavity was formed by ancient supernovae that went off some 10 million years ago.

The mysterious cavity is surrounded by the Perseus and Taurus molecular clouds — regions in space where stars form.

“Hundreds of stars are forming or exist already at the surface of this giant bubble,” says Shmuel Bialy, a postdoctoral researcher at the Institute for Theory and Computation (ITC) at the Center for Astrophysics (CfA) who led the study. “We have two theories—either one supernova went off at the core of this bubble and pushed gas outward forming what we now call the ‘Perseus-Taurus Supershell,’ or a series of supernovae occurring over millions of years created it over time.”

The finding suggests that the Perseus and Taurus molecular clouds are not independent structures in space. But rather, they formed together from the very same supernova shockwave. “This demonstrates that when a star dies, its supernova generates a chain of events that may ultimately lead to the birth of new stars,” Bialy explains.

Mapping Stellar Nurseries

The 3D map of the bubble and surrounding clouds were created using new data from Gaia, a space-based observatory launched by the European Space Agency (ESA).

Descriptions of exactly how 3D maps of the Perseus and Taurus molecular clouds and other nearby clouds were analyzed appear in a separate study published today in the Astrophysical Journal (ApJ). Both studies make use of a dust reconstruction created by researchers at the Max Planck Institute for Astronomy in Germany.

The maps represent the first-time molecular clouds have been charted in 3D. Previous images of the clouds were constrained to two dimensions.

“We’ve been able to see these clouds for decades, but we never knew their true shape, depth, or thickness. We also were unsure how far away the clouds were,” says Catherine Zucker, a postdoctoral researcher at the CfA who led the ApJ study. “Now we know where they lie with only 1 percent uncertainty, allowing us to discern this void between them.”

But why map clouds in the first place?

“There are many different theories for how gas rearranges itself to form stars,” Zucker explains. “Astronomers have tested these theoretical ideas using simulations in the past, but this is the first time we can use real — not simulated — 3D views to compare theory to observation, and evaluate which theories work best.”

The Universe at Your Fingertips

The new research marks the first time journals of the American Astronomical Society (AAS) publish astronomy visualizations in augmented reality. Scientists and the public may interact with the visualization of the cavity and its surrounding molecular clouds by simply scanning a QR code in the paper with their smartphone.

“You can literally make the universe float over your kitchen table,” says Harvard professor and CfA astronomer Alyssa Goodman, a co-author on both studies and founder of glue, the data visualization software that was used to create the maps of molecular clouds.

Goodman calls the new publications examples of the “paper of the future” and considers them important steps toward the interactivity and reproducibility of science, which AAS committed to in 2015 as part of their effort to modernize publications.

“We need richer records of scientific discovery,” Goodman says. “And current scholarly papers could be doing much better. All of the data in these papers are available online — on Harvard’s Dataverse — so that anyone can build on our results.”

Goodman envisions future scientific articles where audio, video and enhanced visuals are regularly included, allowing all readers to more easily understand the research presented.

She says, “It’s 3D visualizations like these that can help both scientists and the public understand what’s happening in space and the powerful effects of supernovae.”

References:

“The Per-Tau Shell: A Giant Star-forming Spherical Shell Revealed by 3D Dust Observations” by Shmuel Bialy, Catherine Zucker, Alyssa Goodman, Michael M. Foley, João Alves, Vadim A. Semenov, Robert Benjamin, Reimar Leike and Torsten Enßlin, 22 September 2021, Astrophysical Journal Letters. DOI: 10.3847/2041-8213/ac1f95

22 September 2021,, Astrophysical Journal.
DOI: 10.3847/1538-4357

NASA’s InSight Finds Three Big Marsquakes, Thanks to Solar-Panel Dusting


The lander cleared enough dust from one solar panel to keep its seismometer on through the summer, allowing scientists to study the three biggest quakes they’ve seen on Mars.

On Sept. 18, NASA’s InSight lander celebrated its 1,000th Martian day, or sol, by measuring one of the biggest, longest-lasting marsquakes the mission has ever detected. The temblor is estimated to be about a magnitude 4.2 and shook for nearly an hour-and-a-half.

This is the third major quake InSight has detected in a month: On Aug. 25, the mission’s seismometer detected two quakes of magnitudes 4.2 and 4.1. For comparison, a magnitude 4.2 quake has five times the energy of the mission’s previous record holder, a magnitude 3.7 quake detected in 2019.

The mission studies seismic waves to learn more about Mars' interior. The waves change as they travel through a planet's crust, mantle, and core, providing scientists a way to peer deep below the surface. What they learn can shed light on how all rocky worlds form, including Earth and its Moon.

The quakes might not have been detected at all had the mission not taken action earlier in the year, as Mars' highly elliptical orbit took it farther from the Sun. Lower temperatures required the spacecraft to rely more on its heaters to keep warm; that, plus dust buildup on InSight's solar panels, has reduced the lander's power levels, requiring the mission to conserve energy by temporarily turning off certain instruments.

The team managed to keep the seismometer on by taking a counterintuitive approach: They used InSight's robotic arm to trickle sand near one solar panel in the hopes that, as wind gusts carried it across the panel, the granules would sweep off some of the dust. The plan worked, and over several dust-clearing activities, the team saw power levels remain fairly steady. Now that Mars is approaching the Sun once again, power is starting to inch back up.

"If we hadn't acted quickly earlier this year, we might have missed out on some great science," said InSight's principal investigator, Bruce Banerdt of NASA's Jet Propulsion Laboratory in Southern California, which leads the mission. "Even after more than two years, Mars seems to have given us something new with these two quakes, which have unique characteristics."

Temblor Insights

While the Sept. 18 quake is still being studied, scientists already know more about the Aug. 25 quakes: The magnitude 4.2 event occurred about 5,280 miles (8,500 kilometers) from InSight—the most distant temblor the lander has detected so far.

Scientists are working to pinpoint the source and which direction the seismic waves traveled, but they know the shaking occurred too far to have originated where InSight has detected almost all of its previous large quakes: Cerberus Fossae, a region roughly 1,000 miles (1,609 kilometers) away where lava may have flowed within the last few million years. One especially intriguing possibility is Valles Marineris, the epically long canyon system that scars the Martian equator. The approximate center of that canyon system is 6,027 miles (9,700 kilometers) from InSight.

To the surprise of scientists, the Aug. 25 quakes were two different types, as well. The magnitude 4.2 quake was dominated by slow, low-frequency vibrations, while fast, high-frequency vibrations characterized the magnitude 4.1 quake. The magnitude 4.1 quake was also much closer to the lander—only about 575 miles (925 kilometers) away.

That's good news for seismologists: Recording different quakes from a range of distances and with different kinds of seismic waves provides more information about a planet's inner structure. This summer, the mission's scientists used previous marsquake data to detail the depth and thickness of the planet's crust and mantle, plus the size of its molten core.

Despite their differences, the two August quakes do have something in common other than being big: Both occurred during the day, the windiest—and, to a seismometer, noisiest—time on Mars. InSight's seismometer usually finds marsquakes at night, when the planet cools off and winds are low. But the signals from these quakes were large enough to rise above any noise caused by wind.

Looking ahead, the mission's team is considering whether to perform more dust cleanings after Mars solar conjunction, when Earth and Mars are on opposite sides of the Sun. Because the Sun's radiation can affect radio signals, interfering with communications, the team will stop issuing commands to the lander on Sept. 29, though the seismometer will continue to listen for quakes throughout conjunction.

Source: Link