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(5 August 2020 – NASA Goddard) Scientists have developed a new prediction of the shape of the bubble surrounding our solar system using a model developed with data from NASA missions.

All the planets of our solar system are encased in a magnetic bubble, carved out in space by the Sun’s constantly outflowing material, the solar wind. Outside this bubble is the interstellar medium — the ionized gas and magnetic field that fills the space between stellar systems in our galaxy. One question scientists have tried to answer for years is on the shape of this bubble, which travels through space as our Sun orbits the center of our galaxy. Traditionally, scientists have thought of the heliosphere as a comet shape, with a rounded leading edge, called the nose, and a long tail trailing behind.

Research published in Nature Astronomy in March and featured on the journal’s cover for July provides an alternative shape that lacks this long tail: the deflated croissant.

An updated model suggests the shape of the Sun’s bubble of influence, the heliosphere (seen in yellow), may be a deflated croissant shape, rather than the long-tailed comet shape suggested by other research. (courtesy: Opher, et al)

The shape of the heliosphere is difficult to measure from within. The closest edge of the heliosphere is more than ten billion miles from Earth. Only the two Voyager spacecraft have directly measured this region, leaving us with just two points of ground-truth data on the shape of the heliosphere.

From near Earth, we study our boundary to interstellar space by capturing and observing particles flying toward Earth. This includes charged particles that come from distant parts of the galaxy, called galactic cosmic rays, along with those that were already in our solar system, travel out towards the heliopause, and are bounced back towards Earth through a complex series of electromagnetic processes. These are called energetic neutral atoms, and because they are created by interacting with the interstellar medium, they act as a useful proxy for mapping the edge of the heliosphere. This is how NASA’s Interstellar Boundary Explorer, or IBEX, mission studies the heliosphere, making use of these particles as a kind of radar, tracing out our solar system’s boundary to interstellar space.

To make sense of this complex data, scientists use computer models to turn this data into a prediction of the heliosphere’s characteristics. Merav Opher, lead author of the new research, heads a NASA- and NSF-funded DRIVE Science Center at Boston University focused on the challenge.

This latest iteration of Opher’s model uses data from NASA planetary science missions to characterize the behavior of material in space that fills the bubble of the heliosphere and get another perspective on its borders. NASA’s Cassini mission carried an instrument, designed to study particles trapped in Saturn’s magnetic field, that also made observations of particles bouncing back towards the inner solar system. These measurements are similar to IBEX’s, but provide a distinct perspective on the heliosphere’s boundary.

Additionally, NASA’s New Horizons mission has provided measurements of pick-up ions, particles that are ionized out in space and are picked up and move along with the solar wind. Because of their distinct origins from the solar wind particles streaming out from the Sun, pick-up ions are much hotter than other solar wind particles — and it’s this fact that Opher’s work hinges on.

“There are two fluids mixed together. You have one component that is very cold and one component that is much hotter, the pick-up ions,” said Opher, a professor of astronomy at Boston University. “If you have some cold fluid and hot fluid, and you put them in space, they won’t mix — they will evolve mostly separately. What we did was separate these two components of the solar wind and model the resulting 3D shape of the heliosphere.”

Considering the solar wind’s components separately, combined with Opher’s earlier work using the solar magnetic field as a dominant force in shaping the heliosphere, created a deflated croissant shape, with two jets curling away from the central bulbous part of the heliosphere, and notably lacking the long tail predicted by many scientists.

“Because the pick-up ions dominate the thermodynamics, everything is very spherical. But because they leave the system very quickly beyond the termination shock, the whole heliosphere deflates,” said Opher.

The shape of our shield

The shape of the heliosphere is more than a question of academic curiosity: The heliosphere acts our solar system’s shield against the rest of the galaxy.

Energetic events in other star systems, like supernova, can accelerate particles to nearly the speed of light. These particles rocket out in all directions, including into our solar system. But the heliosphere acts as a shield: It absorbs about three-quarters of these tremendously energetic particles, called galactic cosmic rays, that would make their way into our solar system.

Those that do make it through can wreak havoc. We’re protected on Earth by our planet’s magnetic field and atmosphere, but technology and astronauts in space or on other worlds are exposed. Both electronics and human cells can be damaged by the effects of galactic cosmic rays — and because galactic cosmic rays carry so much energy, they’re difficult to block in a way that’s practical for space travel. The heliosphere is spacefarers’ main defense against galactic cosmic rays, so understanding its shape and how that influences the rate of galactic cosmic rays pelting our solar system is a key consideration for planning robotic and human space exploration.

The heliosphere’s shape is also part of the puzzle for seeking out life on other worlds. The damaging radiation from galactic cosmic rays can render a world uninhabitable, a fate avoided in our solar system because of our strong celestial shield. As we learn more about how our heliosphere protects our solar system — and how that protection may have changed throughout the solar system’s history — we can look for other star systems that might have similar protection. And part of that is the shape: Are our heliospheric lookalikes long-tailed comet shapes, deflated croissants, or something else entirely?

Whatever the heliosphere’s true shape, an upcoming NASA mission will be a boon for unraveling these questions: the Interstellar Mapping and Acceleration Probe, or IMAP.

IMAP, slated for launch in 2024, will map the particles streaming back to Earth from the boundaries of the heliosphere. IMAP will build on the techniques and discoveries of the IBEX mission to shed new light on the nature of the heliosphere, interstellar space, and how galactic cosmic rays make their way into our solar system.

Opher’s DRIVE Science Center aims to create a testable model of the heliosphere in time for IMAP’s launch. Their predictions of the shape and other characteristics of the heliosphere — and how that would be reflected in the particles streaming back from the boundary — would provide a baseline for scientists to compare with IMAP’s data.

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Preparations for next moonwalk simulations underway

Preparations for next moonwalk simulations underway

(23 September 2020 – NASA) NASA engineers are laying the foundation for the moonwalks the first woman and next man will conduct when they land on the lunar South Pole in 2024 as part of the Artemis program.

At the agency’s Johnson Space Center in Houston, teams are testing the tools and developing training approaches for lunar surface operations.

As part of a test series occurring in the Neutral Buoyancy Lab (NBL) at Johnson, astronauts in a demonstration version of the exploration spacesuit and engineers in “hard hat” dive equipment are simulating several different tasks crew could do on the surface of the Moon.

Teams are evaluating how to train for lunar surface operations during Artemis missions, in the Neutral Buoyancy Lab at Johnson Space Center in Houston. (courtesy: NASA)

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NASA will use a range of facilities to prepare for mission to the Moon. (courtesy: NASA)

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Teams are assessing how to use tools and spacesuits, among other activities, during lunar testing activities in the NBL. (courtesy: NASA)

“This early testing will help determine the best complement of facilities for hardware development and requirements for future Artemis training and missions,” said Daren Welsh, extravehicular activity test lead for these Artemis preparation test runs. “At the same time, we are going to be able to gather valuable feedback on spacewalk tools and procedures that will help inform some of the objectives for the missions.”

The tests are focused on evaluating Johnson’s facilities for Artemis spacewalk testing, development, and crew training. Astronauts are practicing a variety of tasks, including picking up samples of lunar regolith, examining a lunar lander, and planting an American flag. There are many fundamentals that the teams have to consider and work through, such as how crew might get up and down a ladder safely, how to swing a chisel safely, and how to conduct successful moonwalks in different lighting conditions than the Apollo-era moonwalks. The tests will inform future mission planning, including how many spacewalks to conduct during a mission, how long they’ll be, and how far away from a lander the crew will travel.

While NASA has extensive experience preparing astronauts for spacewalks in microgravity like those to construct and maintain the International Space Station over the past 20 years, preparing for Moon missions comes with different challenges.

“We can evaluate tools in a lab or the rock yard, but you can learn so much when you put a pressurized spacesuit on and have to work within the limitations of its mobility,” Welsh said. “These NBL runs are so valuable for understanding the human performance component and ensuring our astronauts are as safe as possible.”

In addition to testing in the NBL, teams also are using different analog environments to simulate lunar conditions. Tests are occurring at Johnson’s rock yard, a large, outdoor test area which simulates general features of the lunar surface terrain.

Rock yard testing is a critical analog environment for spacewalk tool development and operations. The interaction between the crewmembers and the Earth-based teams in mission control and the science control centers allows engineers to mature concepts of mission operations. The testing reveals spacewalking tool design improvements and helps formulate operational timelines. Analog environments allow iterations on designs to occur quickly such that the revisions can be reevaluated in subsequent tests.

“We have experience with space station, but we need to determine how we’re going to train the crew for surface operations during these specific missions,” Welsh said. “There is a lot of work to do to get the facilities ready to work for lunar missions and figure out how to facilitate the training.”

This collaborative effort is already paying dividends for the team as they are becoming more familiar with the surface operation concepts. As the tests continue, the team is expanding the scope of the testing, with plans to complete full lunar spacewalk timelines.

With the Artemis program, NASA will land the first woman and next man on the Moon in 2024, using innovative technologies to explore more of the lunar surface than ever before. We will collaborate with our commercial and international partners and establish sustainable exploration by the end of the decade. Then, we will use what we learn on and around the Moon to take the next giant leap – sending astronauts to Mars.

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SpaceBridge rolls out Integrasys Satmotion facilitating the deployment of customer networks across Greece

SpaceBridge rolls out Integrasys Satmotion facilitating the deployment of customer

(21 September 2020 – Integrasys) SpaceBridge has successfully rolled out an ASAT-II Redundant Hub and over 100 sites across Hellas SAT.

To facilitate the deployment of the network and minimize staff time and efforts on-site, SpaceBridge selected Satmotion Pocket, Integrasys’s industry-leading Auto Commissioning tool. Satmotion Pocket is a VSAT auto-commissioning system that minimizes deployment time and effort while ensuring the highest quality and interference-free installation for optimal performance. It is a software-based solution that simplifies and guides installers by providing feedback on important key performance indicators (KPI) such as Copol, Xpol and Adjacent Satellite Interference, verifying that the antenna and receive/transmit chain of the solutions are optimally installed and allowing sites to generate revenue earlier.

(courtesy: Integrasys)

David Gelerman, President and CEO of Spacebridge; “Our goal at SpaceBridge is to ensure our customers can rapidly monetize upon the offering of their value-added services. The Satmotion Pocket by Integrasys proved very effective in that it allowed our partners to provide high-quality installations efficiently resulting in much faster deployment, saving time and resources, and delivering revenue sooner. Based on this roll-out, we envision a bright future of collaboration between our two companies.”

Alvaro Sanchez; “For us partnering with SpaceBridge has been a great pleasure, it opens the door to new customers who can tangibly benefit from our technology for simplifying the access while generating additional revenue and faster time to market, and commissioning. SpaceBridge is a great company to work with a great leader & engineer as CEO; they have great technology for connecting new networks, ASAT is a fantastic product.”

Satmotion Pocket developed by Integrasys for ASAT System with its accurate performance enabled SpaceBridge customers to deploy the VSAT network rapidly, easily, and at low cost. Satmotion Pocket is supported on the smartphone, thanks to its user-friendly interface, it does not require VSAT experts to carry out the installation. The time and cost savings are remarkable, as the field technician does not need to call the NOC/Hub, carry a satellite phone, or spectrum analyzer, in a few minutes the VSAT is up and running providing revenue to Space Bridge customers.

About Integrasys

Founded in 1990 by Hewlett Packard engineers, Integrasys specializes in providing satellite spectrum monitoring systems for the satellite, telecommunication, and broadcast markets. Its solutions enable fast and efficient installation and monitoring, helping reduce both errors and costs.

Integrasys is a fast-growing company which it has been awarded with the most innovative technology award in 2018 at the Satellite show by WTA; it has increased 30% in revenue each year during the last three years, and last year it has tripled its profit.

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NASA’s new Mars rover will use X-rays to hunt fossils

NASAs new Mars rover will use X rays to hunt fossils

(22 September 2020 – JPL) NASA’s Mars 2020 Perseverance rover has a challenging road ahead: After having to make it through the harrowing entry, descent, and landing phase of the mission on Feb. 18, 2021, it will begin searching for traces of microscopic life from billions of years back.

That’s why it’s packing PIXL, a precision X-ray device powered by artificial intelligence (AI).

Short for Planetary Instrument for X-ray Lithochemistry, PIXL is a lunchbox-size instrument located on the end of Perseverance’s 7-foot-long (2-meter-long) robotic arm. The rover’s most important samples will be collected by a coring drill on the end of the arm, then stashed in metal tubes that Perseverance will deposit on the surface for return to Earth by a future mission.

In this illustration, NASA’s Perseverance Mars rover uses the Planetary Instrument for X-ray Lithochemistry (PIXL). Located on the turret at the end of the rover’s robotic arm, the X-ray spectrometer will help search for signs of ancient microbial life in rocks. (courtesy: NASA/JPL-Caltech)

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PIXL requires pictures of its rock targets to autonomously position itself. Light diodes encircle its opening and take pictures of rock targets when the instrument is working at night. Using artificial intelligence, PIXL relies on the images to determine how far away it is from a target to be scanned. (courtesy: NASA/JPL-Caltech)

Nearly every mission that has successfully landed on Mars, from the Viking landers to the Curiosity rover, has included an X-ray fluorescence spectrometer of some kind. One major way PIXL differs from its predecessors is in its ability to scan rock using a powerful, finely-focused X-ray beam to discover where – and in what quantity – chemicals are distributed across the surface.

“PIXL’s X-ray beam is so narrow that it can pinpoint features as small as a grain of salt. That allows us to very accurately tie chemicals we detect to specific textures in a rock,” said Abigail Allwood, PIXL’s principal investigator at NASA’s Jet Propulsion Laboratory in Southern California.

Rock textures will be an essential clue when deciding which samples are worth returning to Earth. On our planet, distinctively warped rocks called stromatolites were made from ancient layers of bacteria, and they are just one example of fossilized ancient life that scientists will be looking for.

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A device with six mechanical legs, the hexapod is a critical part of the PIXL instrument aboard NASA’s Perseverance Mars rover. The hexapod allows PIXL to make slow, precise movements to get closer to and point at specific parts of a rock’s surface. This GIF has been considerably sped up to show how the hexapod moves. (courtesy: NASA/JPL-Caltech)

An AI-Powered Night Owl

To help find the best targets, PIXL relies on more than a precision X-ray beam alone. It also needs a hexapod – a device featuring six mechanical legs connecting PIXL to the robotic arm and guided by artificial intelligence to get the most accurate aim. After the rover’s arm is placed close to an interesting rock, PIXL uses a camera and laser to calculate its distance. Then those legs make tiny movements – on the order of just 100 microns, or about twice the width of a human hair – so the device can scan the target, mapping the chemicals found within a postage stamp-size area.

“The hexapod figures out on its own how to point and extend its legs even closer to a rock target,” Allwood said. “It’s kind of like a little robot who has made itself at home on the end of the rover’s arm.”

Then PIXL measures X-rays in 10-second bursts from a single point on a rock before the instrument tilts 100 microns and takes another measurement. To produce one of those postage stamp-size chemical maps, it may need to do this thousands of times over the course of as many as eight or nine hours.

That timeframe is partly what makes PIXL’s microscopic adjustments so critical: The temperature on Mars changes by more than 100 degrees Fahrenheit (38 degrees Celsius) over the course of a day, causing the metal on Perseverance’s robotic arm to expand and contract by as much as a half-inch (13 millimeters). To minimize the thermal contractions PIXL has to contend with, the instrument will conduct its science after the Sun sets.

“PIXL is a night owl,” Allwood said. “The temperature is more stable at night, and that also lets us work at a time when there’s less activity on the rover.”

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PIXL opens its dust cover during testing at NASA’s Jet Propulsion Laboratory. One of seven instruments on NASA’s Perseverance Mars rover, PIXL is located on the end of the rover’s robotic arm. (courtesy: NASA/JPL-Caltech)

X-rays for Art and Science

Long before X-ray fluorescence got to Mars, it was used by geologists and metallurgists to identify materials. It eventually became a standard museum technique for discovering the origins of paintings or detecting counterfeits.

“If you know that an artist typically used a certain titanium white with a unique chemical signature of heavy metals, this evidence might help authenticate a painting,” said Chris Heirwegh, an X-ray fluorescence expert on the PIXL team at JPL. “Or you can determine if a particular kind of paint originated in Italy rather than France, linking it to a specific artistic group from the time period.”

For astrobiologists, X-ray fluorescence is a way to read stories left by the ancient past. Allwood used it to determine that stromatolite rocks found in her native country of Australia are some of the oldest microbial fossils on Earth, dating back 3.5 billion years. Mapping out the chemistry in rock textures with PIXL will offer scientists clues to interpret whether a sample could be a fossilized microbe.

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 also characterize the planet’s climate and geology, pave the way for human exploration of the Red Planet, and be the first planetary mission to collect and cache Martian rock and regolith (broken rock and dust). Subsequent missions, currently under consideration by NASA in cooperation with the European Space Agency, would send spacecraft to Mars to collect these cached samples from the surface and return them to Earth for in-depth analysis.

The Mars 2020 mission is part of a larger program that includes missions to the Moon as a way to prepare for human exploration of the Red Planet. Charged with returning astronauts to the Moon by 2024, NASA will establish a sustained human presence on and around the Moon by 2028 through NASA’s Artemis lunar exploration plans.

JPL, which is managed for NASA by Caltech in Pasadena, California, built and manages operations of the Perseverance and Curiosity rovers.

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