Ten Highlights From NASA’s Van Allen Probes Mission

NASA - Van Allen Probes Mission patch.

Oct. 22, 2019

After seven years of operations, and upon finally running out of propellant, the second of the twin Van Allen Probes spacecraft will be retired on Friday, Oct. 18, 2019. Spacecraft A of the Van Allen Probes mission will be shut down by operators at the Johns Hopkins University Applied Physics Lab in Laurel, Maryland. The command follows one three months previously that terminated operations for spacecraft B, the second spacecraft of the mission.

Illustration of Van Allen Probes. Image Credit: JHUAPL

“This mission spent seven years in the radiation belts, and broke all the records for a spacecraft to tolerate and operate in that hazardous region, all with no interruptions,” said Nelofar Mosavi, Van Allen Probes project manager at Johns Hopkins APL. “This mission was about resiliency against the harshest space environment.”

Originally slated for a two-year mission, the spacecraft flew through the Van Allen belts — rings of charged particles trapped by Earth’s magnetic field — to understand how particles were gained and lost by the belts. The spacecraft made major discoveries that revolutionized how we understand our near-Earth environment.

The Van Allen Probes Explore Earth's Radiation Belts

Video above: The Van Allen Probes flew through Earth’s geomagnetic field and radiation belts. Video Credits: NASA's Goddard Space Flight Center.

“Van Allen Probe observations have been the subject of over 600 publications to date in refereed journals, and over 55 Ph.D. theses have used Van Allen Probe observations,” said David Sibeck, Van Allen Probes mission scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

With instruments measuring electromagnetic fields and charged particles, the Van Allen Probes explored the invisible phenomena shepherding particles in and around the belts. It made discoveries about the architecture of the belts and the forces shaping them. Just as ocean storms on Earth can create giant waves, space weather, caused by the Sun, can create plasma waves, where seas of particles are tossed by electromagnetic fields. The Van Allen Probes pioneered new explorations into the dynamics of these waves and their effects on our near-Earth environment.

“The Van Allen Probes rewrote the textbook on radiation belt physics,” said Sasha Ukhorskiy, Van Allen Probes project scientist at Johns Hopkins APL, which also designed and built the spacecraft. “The spacecraft used uniquely capable instruments to unveil radiation belt features that were all but invisible to previous sensors, and discovered many new physical mechanisms of radiation belt acceleration and loss.”

In celebration of the mission’s success, here are ten select discoveries, listed in chronological order, made by the Van Allen Probes.

- The Van Allen belts were first discovered in 1958 and for decades scientists thought there were only two concentric belts. But days after the Van Allen Probes launched, scientists discovered that during times of intense solar activity, a third belt can form.

Image above: Van Allen Probes image showing three radiation belts first seen around Earth in 2012. Image Credits: NASA's Goddard Space Flight Center/Johns Hopkins University, Applied Physics Laboratory.

- The belts, which are composed of charged particles and electromagnetic fields, can be energized by different types of plasma waves. One type, called electrostatic double layers, appear as short blips of enhanced electric field. During one observing period, Probe B saw 7,000 such blips repeatedly pass over the spacecraft in a single minute. These individually small events added up to one million volts over six minutes, capable of accelerating electrons up toward the relativistic energies commonly seen in radiation belt particles.   

- During big space weather storms, which are ultimately caused by activity on the Sun, ions — electrically charged atoms or molecules — can be pushed deep into Earth’s magnetosphere in a series of impulsive events. These particles carry electromagnetic currents that circle around the planet and can dramatically distort Earth’s magnetic field.

Supercharging the Radiation Belts

Image above: On March 17, 2015, Van Allen Probe A detected a pulse of high energy electrons in the radiation belts, generated by the impact of a recent coronal mass ejection striking Earth's magnetosphere. The gradient drift speed of the electron pulse was high enough, that it propagated completely around Earth and was detected by the spacecraft again as the pulse spread out in the radiation belt. Because the particles have a range of energies, the pulse spread out as it moved around Earth, generating a weaker signal the next time it hit the spacecraft. Video Credits: NASA's Goddard Space Flight Center.

- Across space, fluctuating electric and magnetic fields can create what are known as plasma waves. These waves intensify during space weather storms and can accelerate particles to relativistic speeds. The Van Allen Probes found that one type of plasma wave known as hiss can contribute greatly to the loss of electrons from the belts.

- The Van Allen belts are composed of electrons and ions with a range of energies. In 2015, research from the Van Allen Probes found that, unlike the outer belt, there were no electrons with energies greater than a million electron volts in the inner belt.

- Plasma waves known as whistler chorus waves are also common in our near-Earth environment. These waves can travel parallel or at an angle to the local magnetic field. The Van Allen Probes demonstrated the two types of waves cannot be present simultaneously, resulting in greater radiation belt particle scattering in certain areas.

- Very low frequency chorus waves, another variety of plasma waves, can pump up the energy of electrons to millions of electron volts. During storm conditions, the Van Allen Probes found these waves can hugely increase the energy of particles in the belts in just a few hours. 

- Scientists often use computer simulation models to understand the physics behind certain phenomena. A model simulating particles in the Van Allen belts helped scientists understand how particles can be lost, replenished and trapped by the Earth’s magnetic field.

- The Van Allen Probes observed several cases of extremely energetic ions speeding toward Earth. Research found that these ions’ acceleration was connected to their electric charge and not to their mass.

- The Sun emits faster and slower gusts of charged particles called the solar wind. Since the Sun rotates, these gusts — the fast wind — reach Earth periodically. Changes in these gusts cause the extent of region of cold ionized gas around Earth — the plasmasphere — to shrink. Data from the Van Allen Probes showed that such changes in the plasmasphere fluctuated at the same rate as the solar rotation ­— every 27 days.

Related Links:

NASA Mission Surfs through Waves in Space to Understand Space Weather: https://www.nasa.gov/feature/goddard/2017/nasa-mission-surfs-through-waves-in-space-to-understand-space-weather

NASA's Van Allen Probes Spot Man-Made Barrier Shrouding Earth: https://www.nasa.gov/feature/goddard/2017/nasas-van-allen-probes-spot-man-made-barrier-shrouding-earth

Learn more about NASA’s Van Allen Probes: https://www.nasa.gov/van-allen-probes

Research: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018JA025556

Images (mentioned), Videos (mentioned), Text, Credits: NASA/Rob Garner/Goddard Space Flight Center, By Mara Johnson-Groh.

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Hubble Snags Starry Galaxy

NASA - Hubble Space Telescope patch.

Oct. 21, 2019

In this image taken by the Hubble Space Telescope, the galaxy NGC 4380 looks like a special effect straight out of a science fiction or fantasy film, swirling like a gaping portal to another dimension.

In the grand scheme of things, though, the galaxy is actually quite ordinary. Spiral galaxies like NGC 4380 are common in the universe. These colossal collections of stars, often numbering in the hundreds of billions, are shaped like a flat disk, sometimes with a rounded bulge in the center. Graceful spiral arms outlined by dark lanes of dust wind around the bulging core, which glows brightly and has the highest concentration of stars in the galaxy.

 Hubble Space Telescope (HST)

For more information about Hubble, visit:

http://hubblesite.org/

http://www.nasa.gov/hubble

http://www.spacetelescope.org/

Text Credits: ESA (European Space Agency)/NASA/Rob Garner/Image Credits: ESA/Hubble & NASA, P. Erwin.

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2019 Ozone Hole is the Smallest on Record Since Its Discovery

NASA logo.

Oct. 21, 2019

Abnormal weather patterns in the upper atmosphere over Antarctica dramatically limited ozone depletion in September and October, resulting in the smallest ozone hole observed since 1982, NASA and NOAA scientists reported today.

Unusual Winds Drive a Small 2019 Ozone Hole

Video above: Scientists from NASA and NOAA work together to track the ozone layer throughout the year and determine when the hole reaches its annual maximum extent. This year, unusually strong weather patterns caused warm temperatures in the upper atmosphere above the South Pole region of Antarctic, which resulted in a small ozone hole. Image Credits: NASA Goddard/ Katy Mersmann.

The annual ozone hole reached its peak extent of 6.3 million square miles (16. 4 million square kilometers) on Sept. 8, and then shrank to less than 3.9 million square miles (10 million square kilometers) for the remainder of September and October, according to NASA and NOAA satellite measurements. During years with normal weather conditions, the ozone hole typically grows to a maximum area of about 8 million square miles in late September or early October.

“It’s great news for ozone in the Southern Hemisphere,” said Paul Newman, chief scientist for Earth Sciences at NASA's Goddard Space Flight Center in Greenbelt, Maryland. “But it’s important to recognize that what we’re seeing this year is due to warmer stratospheric temperatures. It’s not a sign that atmospheric ozone is suddenly on a fast track to recovery.”

Image above: The 2019 ozone hole reached its peak extent of 6.3 million square miles (16. 4 million square kilometers) on Sept. 8. Abnormal weather patterns in the upper atmosphere over Antarctica dramatically limited ozone depletion this year. Image Credit: NASA.

Ozone is a highly reactive molecule comprised of three oxygen atoms that occurs naturally in small amounts. Roughly seven to 25 miles above Earth’s surface, in a layer of the atmosphere called the stratosphere, the ozone layer is a sunscreen, shielding the planet from potentially harmful ultraviolet radiation that can cause skin cancer and cataracts, suppress immune systems and also damage plants.

The Antarctic ozone hole forms during the Southern Hemisphere’s late winter as the returning Sun’s rays start ozone-depleting reactions. These reactions involve chemically active forms of chlorine and bromine derived from man-made compounds. The chemistry that leads to their formation involves chemical reactions that occur on the surfaces of cloud particles that form in cold stratospheric layers, leading ultimately to runaway reactions that destroy ozone molecules. In warmer temperatures fewer polar stratospheric clouds form and they don’t persist as long, limiting the ozone-depletion process.

NASA and NOAA monitor the ozone hole via complementary instrumental methods.

Satellites, including NASA’s Aura satellite, the NASA-NOAA Suomi National Polar-orbiting Partnership satellite and NOAA’s Joint Polar Satellite System NOAA-20 satellite, measure ozone from space. The Aura satellite’s Microwave Limb Sounder also estimates levels of ozone-destroying chlorine in the stratosphere.

At the South Pole, NOAA staff launch weather balloons carrying ozone-measuring “sondes” which directly sample ozone levels vertically through the atmosphere. Most years, at least some levels of the stratosphere, the region of the upper atmosphere where the largest amounts of ozone are normally found, are found to be completely devoid of ozone.

“This year, ozonesonde measurements at the South Pole did not show any portions of the atmosphere where ozone was completely depleted,” said atmospheric scientist Bryan Johnson at NOAA’s Earth System Research Laboratory in Boulder, Colorado.

Uncommon but not unprecedented

This is the third time in the last 40 years that weather systems have caused warm temperatures that limit ozone depletion, said Susan Strahan, an atmospheric scientist with Universities Space Research Association, who works at NASA Goddard. Similar weather patterns in the Antarctic stratosphere in September 1988 and 2002 also produced atypically small ozone holes, she said.

“It’s a rare event that we’re still trying to understand,” said Strahan. “If the warming hadn’t happened, we’d likely be looking at a much more typical ozone hole.”

There is no identified connection between the occurrence of these unique patterns and changes in climate.

The weather systems that disrupted the 2019 ozone hole are typically modest in September, but this year they were unusually strong, dramatically warming the Antarctic’s stratosphere during the pivotal time for ozone destruction. At an altitude of about 12 miles (20 kilometers), temperatures during September were 29 degrees F (16˚C) warmer than average, the warmest in the 40-year historical record for September by a wide margin. In addition, these weather systems also weakened the Antarctic polar vortex, knocking it off its normal center over the South Pole and reducing the strong September jet stream around Antarctica from a mean speed of 161 miles per hour to a speed of 67 miles per hour. This slowing vortex rotation allowed air to sink in the lower stratosphere where ozone depletion occurs, where it had two impacts.

First, the sinking warmed the Antarctic lower stratosphere, minimizing the formation and persistence of the polar stratospheric clouds that are a main ingredient in the ozone-destroying process. Second, the strong weather systems brought ozone-rich air from higher latitudes elsewhere in the Southern Hemisphere to the area above the Antarctic ozone hole. These two effects led to much higher than normal ozone levels over Antarctica compared to ozone hole conditions usually present since the mid 1980s.

As of October 16, the ozone hole above Antarctica remained small but stable and is expected to gradually dissipate in the coming weeks.

Image above: This time-lapse photo from Sept. 9, 2019, shows the flight path of an ozonesonde as it rises into the atmosphere over the South Pole from the Amundsen-Scott South Pole Station. Scientists release these balloon-borne sensors to measure the thickness of the protective ozone layer high up in the atmosphere. Image Credits: Robert Schwarz/University of Minnesota.

Antarctic ozone slowly decreased in the 1970s, with large seasonal ozone deficits appearing in the early 1980s. Researchers at the British Antarctic Survey discovered the ozone hole in 1985, and NASA’s satellite estimates of total column ozone from the Total Ozone Mapping Spectrometer confirmed the 1985 event, revealing the ozone hole’s continental scale.

Thirty-two years ago, the international community signed the Montreal Protocol on Substances that Deplete the Ozone Layer. This agreement regulated the consumption and production of ozone-depleting compounds. Atmospheric levels of man-made ozone depleting substances increased up to the year 2000. Since then, they have slowly declined but remain high enough to produce significant ozone loss. The ozone hole over Antarctica is expected to gradually become less severe as chlorofluorocarbons— banned chlorine-containing synthetic compounds that were once frequently used as coolants—continue to decline. Scientists expect the Antarctic ozone to recover back to the 1980 level around 2070.

To learn more about NOAA and NASA efforts to monitor the ozone and ozone-depleting gases, visit:

https://ozonewatch.gsfc.nasa.gov/

https://www.cpc.ncep.noaa.gov/products/stratosphere/polar/polar.shtml

https://www.esrl.noaa.gov/gmd/dv/spo_oz/

Images (mentioned), Video (mentioned), Text, Credits: NASA/Sara Blumberg/Earth Science News Team, by Ellen Gray/National Oceanic and Atmospheric Administration (NOAA), By Theo Stein.

Greetings, Orbiter.ch

Eye Checks and Maintenance During Spacewalk Cleanup Today

ISS - Expedition 61 Mission patch / EVA - Extra Vehicular Activities patch.

October 21, 2019

The Expedition 61 crew is cleaning up today after the first all-woman spacewalk at the International Space Station. Eye checks and lab maintenance also kicked off the workweek as two cosmonauts took the day off.

NASA astronauts Christina Koch and Jessica Meir are stowing the tools they used on Friday during a seven-hour and 17-minute spacewalk. Koch is also packing a failed power controller for return to Earth after replacing it with spare unit during last week’s excursion. Meir recorded how she felt about the first spacewalk of her career for a 3-D virtual reality film.

Image above: Spacewalkers Christina Koch and Jessica Meir are pictured during the first all-woman spacewalk that lasted seven hours and 17 minutes. Image Credit: NASA.

During the afternoon, Meir joined Commander Luca Parmitano and fellow Flight Engineer Andrew Morgan for eye exams. The trio took turns peering into Optical Coherence Tomography hardware so ground doctors could check the astronauts’ retinas.

Morgan partnered with Koch in the morning transferring hardware from the Permanent Multipurpose Module to Japan’s HTV-8 resupply ship. The HTV-8 will complete its 34-day cargo mission at the station’s Harmony module on Nov. 1.

Image above: NASA astronaut Christina Koch conducts her fourth spacewalk at the International Space Station. She and fellow NASA astronaut Jessica Meir (out of frame) ventured into the vacuum of space for seven hours and 17 minutes on Oct. 18, 2019, to swap a failed battery charge-discharge unit (BCDU) with a spare during the first all-woman spacewalk. The BCDU regulates the charge to the batteries that collect and distribute solar power to the orbiting laboratory’s systems. Image Credit: NASA.

Cosmonauts Alexander Skvortsov and Oleg Skripochka are relaxing today after a busy week of space research and maintenance over the station’s Russian segment. The veteran space duo are each on their third long-duration mission at the orbiting lab.

Related links:

Expedition 61: https://www.nasa.gov/mission_pages/station/expeditions/expedition61/index.html

3-D virtual reality film: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7877

Permanent Multipurpose Module (PMM): https://www.nasa.gov/mission_pages/station/structure/elements/permanent-multipurpose-module

HTV-8 resupply ship: https://blogs.nasa.gov/spacestation/2019/09/28/u-s-astronauts-captured-japanese-cargo-spacecraft-at-712-a-m-edt/

Harmony module: https://www.nasa.gov/mission_pages/station/structure/elements/harmony

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Images (mentioned), Text, Credits: NASA/Mark Garcia/Yvette Smith.

Best regards, Orbiter.ch

NASA’s Lucy Mission Clears Critical Milestone

NASA - LUCY Mission patch.

NASA’s Lucy Mission Clears Critical Milestone

Oct. 21, 2019

NASA’s Lucy mission successfully completed its Critical Design Review on Oct. 18.

During this review, Lucy team members presented the completed mission design, demonstrating that the team has met all the technical challenges of the mission and is ready to begin building hardware. After the review completion, NASA's independent review board provided a green light for proceeding into the fabrication/manufacturing stage of the mission.

The Lucy Critical Design Review began on Oct. 15 at Lockheed Martin in Littleton, Colorado. This major mission milestone marks the culmination of months of reviews of all of the mission systems and subsystems. Over four days, the independent review board, comprised of reviewers from NASA and several external organizations, heard presentations on all aspects of the mission design. All aspects of the mission were addressed, including the Lucy spacecraft and its instrument payload, system-level test plans for flight hardware and software, systems engineering, mission assurance, the ground system, and science.

Fossils of Planet Formation: Lucy Mission Teaser

Video above: Beyond the asteroid belt are "fossils of planet formation" known as the Trojan asteroids. These primitive bodies share Jupiter's orbit in two vast swarms, and may hold clues to the formation and evolution of our solar system. NASA is preparing to explore the Trojan asteroids for the first time with a mission called Lucy. Video Credits: NASA's Goddard Space Flight Center.

"This is a very exciting time for us because we are moving beyond the design phase and a really starting to build the spacecraft, said Hal Levison, Lucy principal investigator from Southwest Research Institute in Boulder, Colorado. “It is finally becoming real!"

Critical Design Reviews are one-time programmatic events that bridge the design and manufacturing stages of a project. A successful review means that the design is validated and will meet its requirements, is backed up with solid analysis and documentation, and has been demonstrated to be safe.

Lucy will be the first space mission to study the Trojan asteroids, which orbit the Sun at a distance of Jupiter. The mission will launch in October 2021. With boosts from Earth's gravity, the spacecraft will complete a 12-year journey to seven different asteroids — a Main Belt asteroid and six Trojan asteroids.

“I am constantly amazed at the dedication and diversity of skills that our team brings to this project," said Keith Noll, Lucy project scientist from NASA’s Goddard Space Flight Center in Greenbelt, Maryland. ”Day by day the mission comes into clearer focus and the mission critical design review is the latest milestone in our journey to launch just two years from now.”

Artist's concept of Lucy Mission. Image Credit: SwRI

Southwest Research Institute (SwRI) in Boulder, Colorado is the principal investigator institution and will lead the science investigation. NASA’s Goddard Space Flight Center, Greenbelt, Maryland will provide overall mission management, systems engineering, and safety and mission assurance. Lockheed Martin Space Systems in Denver, Colorado will build the spacecraft.

Discovery Program class missions like Lucy are relatively low-cost; their development is capped at about $450 million. They are managed for NASA’s Planetary Science Division by the Planetary Missions Program Office at Marshall Space Flight Center in Huntsville, Alabama. The missions are led by a principal investigator, who assembles a team of scientists and engineers to design and conduct the mission to address key science questions about the Solar System.

For more information about the Lucy mission, visit:

https://www.nasa.gov/lucy or http://lucy.swri.edu

Image (mentioned), Video (mentioned), Text, Credits: NASA/Karl Hille/Goddard Space Flight Center, by Nancy Neal Jones.

Greetings, Orbiter.ch

Orion Suit Equipped to Expect the Unexpected on Artemis Missions

NASA - Orion Crew Vehicle patch.

Oct. 20, 2019

When astronauts are hours away from launching on Artemis missions to the Moon, they’ll put on a brightly colored orange spacesuit called the Orion Crew Survival System (OCSS) suit. It is designed for a custom fit and equipped with safety technology and mobility features to help protect astronauts on launch day, in emergency situations, high-risk parts of missions near the Moon, and during the high-speed return to Earth.

Many missions require two spacesuits – one worn outside a spacecraft during spacewalks that is designed as a self-contained personal spaceship, and another worn inside a spacecraft during high-risk parts of a mission, such as inside Orion during launch and reentry through Earth’s atmosphere. NASA is building both for Artemis missions. Drawing on six decades of spaceflight experience, NASA is developing its Exploration Extravehicular Mobility Unit, or xEMU, for moonwalks, and has reengineered elements of the crew survival suit worn on the space shuttle to enhance range of motion and improve safety for the astronauts who will wear it to get to the Moon and back to Earth.

The Orion suit, sometimes called a flight suit or a launch and entry suit, has been enhanced from head to toe with improvements to the suit worn on shuttle missions. Starting at the top, a number of features on the helmet allow for improved comfort and function. The helmet is lighter, stronger, comes in more than one size, helps reduce noise and is easier to connect to the communications system needed to talk to other crew members and mission control.

Image above: NASA is building the Orion Crew Survival System spacesuit to protect astronauts during launch, reentry and emergency situations during Artemis missions. Image Credit: NASA.

The outer cover layer, which is orange to make crew members easily recognizable in the ocean should they ever need to exit Orion without the assistance of recovery personnel, includes shoulder enhancements for better reach and is fire resistant. The suit is a pressure garment that includes a restraint layer to control the shape and ease astronauts’ movements. A reengineered zipper also allows astronauts to quickly put the suit on and has increased strength. New adaptable interfaces supply air and remove exhaled carbon-dioxide. The suit has and improved thermal management that will help keep astronauts cool and dry. A liquid cooling garment is worn underneath the suit, a bit like thermal underwear with embedded cooling tubes, was revamped to be more breathable and easier to build.

 #AskNASA ┃ What are the Next Generation Spacesuits

While shuttle-era spacesuits came in off-the-shelf sizes like small, medium and large, the Orion suits will be custom fit for each crew member and accommodate astronauts of all sizes. The patterns of the suit now minimize the spots of discomfort common during the shuttle era when worn pressurized for long periods of time. The suits’ gloves, the part of a spacesuit that receives the most wear and tear, are more durable and touch-screen compatible, and improvements to the boots provide protection in the case of fire, fit better, and help an astronaut move more nimbly.

Even though it’s primarily designed for launch and reentry, the Orion suit can keep astronauts alive if Orion were to lose cabin pressure during the journey out to the Moon, while adjusting orbits in Gateway, or on the way back home. Astronauts could survive inside the suit for up to six days as they make their way back to Earth. The suits are also equipped with a suite of survival gear in the event they have to exit Orion after splashdown before recovery personnel arrive. Each suit will carry its own life preserver that contains a personal locator beacon, a rescue knife, and a signaling kit with a mirror, strobe light, flashlight, whistle, and light sticks.

Through extensive design and engineering enhancements, the Orion suit will help provide an additional layer of protection for astronauts who embark on Artemis missions to the Moon and prepare for future missions to Mars.

For more information about NASA’s Moon to Mars exploration plans visit: https://nasa.gov/moontomars

Related links:

Artemis: https://www.nasa.gov/artemis

SuitUp: https://www.nasa.gov/suitup

Orion Spacecraft: https://www.nasa.gov/exploration/systems/orion/index.html

Image (mentioned), Video (NASA), Text, Credits: NASA/Aimee Crane.

Greetings, Orbiter.ch

Mars InSight's 'Mole' Is Moving Again

NASA - InSight Mission patch.

October 18, 2019

NASA's InSight spacecraft has used its robotic arm to help its heat probe, known as "the mole," dig nearly 2 centimeters (3/4 of an inch) over the past week. While modest, the movement is significant: Designed to dig as much as 16 feet (5 meters) underground to gauge the heat escaping from the planet's interior, the mole has only managed to partially bury itself since it started hammering in February 2019.

Animation above: This GIF shows NASA InSight's heat probe, or "mole," digging about a centimeter (half an inch) below the surface last week. Using a technique called "pinning," InSight recently pressed the scoop on its robotic arm against the self-hammering mole in order to help it dig. Animation Credit: NASA/JPL-Caltech.

The recent movement is the result of a new strategy, arrived at after extensive testing on Earth, which found that unexpectedly strong soil is holding up the mole's progress. The mole needs friction from surrounding soil in order to move: Without it, recoil from its self-hammering action will cause it to simply bounce in place. Pressing the scoop on InSight's robotic arm against the mole, a new technique called "pinning," appears to provide the probe with the friction it needs to continue digging.

Since Oct. 8, 2019, the mole has hammered 220 times over three separate occasions. Images sent down from the spacecraft's cameras have shown the mole gradually progressing into the ground. It will take more time - and hammering - for the team to see how far the mole can go.

The mole is part of an instrument called the Heat Flow and Physical Properties Package, or HP3, which was provided by the German Aerospace Center (DLR).

"Seeing the mole's progress seems to indicate that there's no rock blocking our path," said HP3 Principal Investigator Tilman Spohn of DLR. "That's great news! We're rooting for our mole to keep going."

NASA's Jet Propulsion Laboratory in Pasadena, California, leads the InSight mission. JPL has tested the robotic arm's movement using full-scale replicas of InSight and the mole. Engineers continue to test what would happen if the mole were to sink beneath the reach of the robotic arm. If it stops making progress, they might scrape soil on top of the mole, adding mass to resist the mole's recoil.

InSight on Mars. Image Credits: NASA/JPL

If no other options exist, they would consider pressing the scoop down directly on the top of the mole while trying to avoid the sensitive tether there; the tether provides power to and relays data from the instrument.

"The mole still has a way to go, but we're all thrilled to see it digging again," said Troy Hudson of JPL, an engineer and scientist who has led the mole recovery effort. "When we first encountered this problem, it was crushing. But I thought, 'Maybe there's a chance; let's keep pressing on.' And right now, I'm feeling giddy."

About InSight

JPL manages InSight for NASA's Science Mission Directorate. InSight is part of NASA's Discovery Program, managed by the agency's Marshall Space Flight Center in Huntsville, Alabama. Lockheed Martin Space in Denver built the InSight spacecraft, including its cruise stage and lander, and supports spacecraft operations for the mission.

A number of European partners, including France's Centre National d'Études Spatiales (CNES) and the German Aerospace Center (DLR), are supporting the InSight mission. CNES provided the Seismic Experiment for Interior Structure (SEIS) instrument to NASA, with the principal investigator at IPGP (Institut de Physique du Globe de Paris). Significant contributions for SEIS came from IPGP; the Max Planck Institute for Solar System Research (MPS) in Germany; the Swiss Federal Institute of Technology (ETH Zurich) in Switzerland; Imperial College London and Oxford University in the United Kingdom; and JPL. DLR provided the Heat Flow and Physical Properties Package (HP3) instrument, with significant contributions from the Space Research Center (CBK) of the Polish Academy of Sciences and Astronika in Poland. Spain's Centro de Astrobiología (CAB) supplied the temperature and wind sensors.

Related article:

NASA's Push to Save the Mars InSight Lander's Heat Probe
https://orbiterchspacenews.blogspot.com/2019/10/nasas-push-to-save-mars-insight-landers.html

More about InSight:

https://mars.nasa.gov/insight/

https://www.nasa.gov/insight/

Seismic Experiment for Interior Structure (SEIS): https://mars.nasa.gov/insight/mission/instruments/seis/

Animation (mentioned), Image (mentioned), Text, Credits: NASA/Alana Johnson/JPL/Andrew Good.

Greetings, Orbiter.ch