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Via NASA Plane, Scientists Find New Gamma-ray Emission in Storm Clouds
Tropical thunderstorm with lightning, near the airport of Santa Marta, Colombia. Credit: Oscar van der Velde There’s more to thunderclouds than rain and lightning. Along with visible light emissions, thunderclouds can produce intense bursts of gamma rays, the most energetic form of light, that last for millionths of a second. The clouds can also glow steadily with gamma rays for seconds to minutes at a time.
Researchers using NASA airborne platforms have now found a new kind of gamma-ray emission that’s shorter in duration than the steady glows and longer than the microsecond bursts. They’re calling it a flickering gamma-ray flash. The discovery fills in a missing link in scientists’ understanding of thundercloud radiation and provides new insights into the mechanisms that produce lightning. The insights, in turn, could lead to more accurate lightning risk estimates for people, aircraft, and spacecraft.
Researchers from the University of Bergen in Norway led the study in collaboration with scientists from NASA’s Marshall Space Flight Center in Huntsville, Alabama, and NASA’s Goddard Space Flight Center in Greenbelt, Maryland, the U.S. Naval Research Laboratory, and multiple universities in the U.S., Mexico, Colombia, and Europe. The findings were described in a pair of papers in Nature, published Oct. 2.
The international research team made their discovery while flying a battery of detectors aboard a NASA ER-2 research aircraft. In July 2023, the ER-2 set out on a series of 10 flights from MacDill Air Force Base in Tampa, Florida. The plane flew figure-eight flight patterns a few miles above tropical thunderclouds in the Caribbean and Central America, providing unprecedented views of cloud activity.
The scientific payload was developed for the Airborne Lightning Observatory for Fly’s Eye Geostationary Lightning Mapper Simulator and Terrestrial Gamma-ray Flashes (ALOFT) campaign. Instrumentation in the payload included weather radars along with multiple sensors for measuring gamma rays, lightning flashes, and microwave emissions from clouds.
NASA’s high-flying ER-2 airplane carries instrumentation in this artist’s impression of the ALOFT mission to record gamma rays (colored purple for illustration) from thunderclouds.Credit: NASA/ALOFT team The researchers had hoped ALOFT instruments would observe fast radiation bursts known as terrestrial gamma-ray flashes (TGFs). The flashes, first discovered in 1992 by NASA’s Compton Gamma Ray Observatory spacecraft, accompany some lightning strikes and last only millionths of a second. Despite their high intensity and their association with visible lightning, few TGFs have been spotted during previous aircraft-based studies.
“I went to a meeting just before the ALOFT campaign,” said principal investigator Nikolai Østgaard, a space physicist with the University of Bergen. “And they asked me: ‘How many TGFs are you going to see?’ I said: ‘Either we’ll see zero, or we’ll see a lot.’ And then we happened to see 130.”
However, the flickering gamma-ray flashes were a complete surprise.
“They’re almost impossible to detect from space,” said co-principal investigator Martino Marisaldi, who is also a University of Bergen space physicist. “But when you are flying at 20 kilometers [12.5 miles] high, you’re so close that you will see them.” The research team found more than 25 of these new flashes, each lasting between 50 to 200 milliseconds.
The abundance of fast bursts and the discovery of intermediate-duration flashes could be among the most important thundercloud discoveries in a decade or more, said University of New Hampshire physicist Joseph Dwyer, who was not involved in the research. “They’re telling us something about how thunderstorms work, which is really important because thunderstorms produce lightning that hurts and kills a lot of people.”
More broadly, Dwyer said he is excited about the prospects of advancing the field of meteorology. “I think everyone assumes that we figured out lightning a long time ago, but it’s an overlooked area … we don’t understand what’s going on inside those clouds right over our heads.” The discovery of flickering gamma-ray flashes may provide crucial clues scientists need to understand thundercloud dynamics, he said.
Turning to aircraft-based instrumentation rather than satellites ensured a lot of bang for research bucks, said the study’s project scientist, Timothy Lang of NASA’s Marshall Space Flight Center in Huntsville, Alabama.
“If we had gotten one flash, we would have been ecstatic — and we got well over 100,” he said. This research could lead to a significant advance in our understanding of thunderstorms and radiation from thunderstorms. “It shows that if you have the right problem and you’re willing to take a little bit of risk, you can have a huge payoff.”
By James Riordon
NASA’s Earth Science News Team
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Last Updated Oct 02, 2024 EditorJenny MarderContactJames RiordonLocationMarshall Space Flight Center Related Terms
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Preparations for Next Moonwalk Simulations Underway (and Underwater)
Tests on Earth appear to confirm how the Red Planet’s spider-shaped geologic formations are carved by carbon dioxide.
Spider-shaped features called araneiform terrain are found in the southern hemisphere of Mars, carved into the landscape by carbon dioxide gas. This 2009 image taken by NASA’s Mars Reconnaissance Orbiter shows several of these distinctive formations within an area three-quarters of a mile (1.2 kilometers) wide. NASA/JPL-Caltech/University of Arizona Dark splotches seen in this example of araneiform terrain captured by NASA’s Mars Reconnaissance Orbiter in 2018 are believed to be soil ejected from the surface by carbon dioxide gas plumes. A set of experiments at JPL has sought to re-create these spider-like formations in a lab. NASA/JPL-Caltech/University of Arizona Since discovering them in 2003 via images from orbiters, scientists have marveled at spider-like shapes sprawled across the southern hemisphere of Mars. No one is entirely sure how these geologic features are created. Each branched formation can stretch more than a half-mile (1 kilometer) from end to end and include hundreds of spindly “legs.” Called araneiform terrain, these features are often found in clusters, giving the surface a wrinkled appearance.
The leading theory is that the spiders are created by processes involving carbon dioxide ice, which doesn’t occur naturally on Earth. Thanks to experiments detailed in a new paper published in The Planetary Science Journal, scientists have, for the first time, re-created those formation processes in simulated Martian temperatures and air pressure.
Here’s a look inside of JPL’s DUSTIE, a wine barrel-size chamber used to simulate the temperatures and air pressure of other planets – in this case, the carbon dioxide ice found on Mars’ south pole. Experiments conducted in the chamber confirmed how Martian formations known as “spiders” are created.NASA/JPL-Caltech “The spiders are strange, beautiful geologic features in their own right,” said Lauren Mc Keown of NASA’s Jet Propulsion Laboratory in Southern California. “These experiments will help tune our models for how they form.”
The study confirms several formation processes described by what’s called the Kieffer model: Sunlight heats the soil when it shines through transparent slabs of carbon dioxide ice that built up on the Martian surface each winter. Being darker than the ice above it, the soil absorbs the heat and causes the ice closest to it to turn directly into carbon dioxide gas — without turning to liquid first — in a process called sublimation (the same process that sends clouds of “smoke” billowing up from dry ice). As the gas builds in pressure, the Martian ice cracks, allowing the gas to escape. As it seeps upward, the gas takes with it a stream of dark dust and sand from the soil that lands on the surface of the ice.
When winter turns to spring and the remaining ice sublimates, according to the theory, the spiderlike scars from those small eruptions are what’s left behind.
These formations similar to the Red Planet’s “spiders” appeared within Martian soil simulant during experiments in JPL’s DUSTIE chamber. Carbon dioxide ice frozen within the simulant was warmed by a heater below, turning it back into gas that eventually cracked through the frozen top layer and formed a plume.NASA/JPL-Caltech Re-Creating Mars in the Lab
For Mc Keown and her co-authors, the hardest part of conducting these experiments was re-creating conditions found on the Martian polar surface: extremely low air pressure and temperatures as low as minus 301 degrees Fahrenheit (minus 185 degrees Celsius). To do that, Mc Keown used a liquid-nitrogen-cooled test chamber at JPL, the Dirty Under-vacuum Simulation Testbed for Icy Environments, or DUSTIE.
“I love DUSTIE. It’s historic,” Mc Keown said, noting that the wine barrel-size chamber was used to test a prototype of a rasping tool designed for NASA’s Mars Phoenix lander. The tool was used to break water ice, which the spacecraft scooped up and analyzed near the planet’s north pole.
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This video shows Martian soil simulant erupting in a plume during a JPL lab experiment that was designed to replicate the process believed to form Martian features called “spiders.” When a researcher who had tried for years to re-create these conditions spotted this plume, she was ecstatic. NASA/JPL-Caltech For this experiment, the researchers chilled Martian soil simulant in a container submerged within a liquid nitrogen bath. They placed it in the DUSTIE chamber, where the air pressure was reduced to be similar to that of Mars’ southern hemisphere. Carbon dioxide gas then flowed into the chamber and condensed from gas to ice over the course of three to five hours. It took many tries before Mc Keown found just the right conditions for the ice to become thick and translucent enough for the experiments to work.
Once they got ice with the right properties, they placed a heater inside the chamber below the simulant to warm it up and crack the ice. Mc Keown was ecstatic when she finally saw a plume of carbon dioxide gas erupting from within the powdery simulant.
“It was late on a Friday evening and the lab manager burst in after hearing me shrieking,” said Mc Keown, who had been working to make a plume like this for five years. “She thought there had been an accident.”
The dark plumes opened holes in the simulant as they streamed out, spewing simulant for as long as 10 minutes before all the pressurized gas was expelled.
The experiments included a surprise that wasn’t reflected in the Kieffer model: Ice formed between the grains of the simulant, then cracked it open. This alternative process might explain why spiders have a more “cracked” appearance. Whether this happens or not seems dependent on the size of soil grains and how embedded water ice is underground.
“It’s one of those details that show that nature is a little messier than the textbook image,” said Serina Diniega of JPL, a co-author of the paper.
What’s Next for Plume Testing
Now that the conditions have been found for plumes to form, the next step is to try the same experiments with simulated sunlight from above, rather than using a heater below. That could help scientists narrow down the range of conditions under which the plumes and ejection of soil might occur.
There are still many questions about the spiders that can’t be answered in a lab. Why have they formed in some places on Mars but not others? Since they appear to result from seasonal changes that are still occurring, why don’t they seem to be growing in number or size over time? It’s possible that they’re left over from long ago, when the climate was different on Mars— and could therefore provide a unique window into the planet’s past.
For the time being, lab experiments will be as close to the spiders as scientists can get. Both the Curiosity and Perseverance rovers are exploring the Red Planet far from the southern hemisphere, which is where these formations appear (and where no spacecraft has ever landed). The Phoenix mission, which landed in the northern hemisphere, lasted only a few months before succumbing to the intense polar cold and limited sunlight.
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Preparations for Next Moonwalk Simulations Underway (and Underwater)
Artist David Bowen works on “tele-present wind,” featuring grass stalks that move in response to Martian wind data previously collected by NASA’s Perseverance rover mission. Behind him sits JPL data systems architect Rishi Verma.NASA/JPL-Caltech Works in ‘Blended Worlds: Experiments in Interplanetary Imagination,’ an exhibit in Glendale, California, help shrink the universe into something tangible.
The universe is vast and filled with countless worlds, but a new exhibit at the Brand Library & Art Center in Glendale, California, aims to shrink time and space. For “Blended Worlds: Experiments in Interplanetary Imagination,” artists collaborated with scientists and engineers from NASA’s Jet Propulsion Laboratory to create cross-disciplinary works that help illuminate the universe by bringing art and science together.
On view from Sept. 21, 2024, to Jan. 4, 2025, the exhibition is part of “PST ART: Art & Science Collide,” an event presented by the Getty and involving more than 70 exhibitions from museums and institutions across Southern California exploring the intersection of art and science.
“The magic of art is that it enhances our experiences and interactions with the world — and in this case, our universe,” said Dr. Laurie Leshin, director of JPL in Southern California. “We’re honored to work with great artists to bring the wonders of space to our community through this exhibition, which invites us all to be part of a grand journey of exploration and discovery.”
The 126 grass stalks of “tele-present wind” are attached to mechanical tilting devices that move in response to Martian wind data.NASA/JPL-Caltech David Bowen’s installation “tele-present wind” features grass stalks attached to tilting mechanical devices that move in response to Martian wind data previously collected by NASA’s Perseverance rover mission. Helping make the effort possible were Rishi Verma, a data systems architect at JPL, and José Antonio Rodríguez-Manfredi, the principal investigator of the Mars Environmental Dynamics Analyzer (MEDA) system on Perseverance.
For “Seismic Percussion,” artist Moon Ribas creates an interplanetary drum score by translating seismic data from Earth, the Moon, and Mars. For Mars data, JPL’s Verma worked with Nobuaki Fuji of the Institut de Physique du Globe de Paris, who collaborated on NASA’s now-retired InSight lander. Ceri Nunn, a JPL planetary scientist, assisted with moonquake data.
Also featured is a handwritten version of U.S. Poet Laureate Ada Limón’s “In Praise of Mystery: A Poem for Europa,” the poem she dedicated to NASA’s Europa Clipper mission, which is targeting an October launch and will make multiple flybys of Jupiter’s icy moon Europa. The poem has been etched onto a metal plate on the spacecraft and will ride with the orbiter on its long journey.
Additional works allow visitors to experience Earth’s wonders through scents, use sound to convey the vast distances between our planet and those beyond our solar system, and blend heartbeats and other Earthly sounds with sonified data from Europa’s magnetic field.
“We were looking to create imaginative opportunities for people to connect with each other as they connect with the awe-inspiring science being conducted today,” said David Delgado, a cultural strategist and the project lead at JPL. “I know this experience has really opened the eyes of everyone collaborating on the project, and we hope it does the same for people who come to see ‘Blended Worlds.’”
As part of PST ART, a number of public programs and community events will also accompany the “Blended Worlds” gallery exhibition, including “Blended Worlds: An Evening of Art, Theater, and Science” hosted by Reggie Watts at the Alex Theatre in Glendale on Oct. 5, and “Earth Data: The Musical,” an original musical developed by Theater Arts at Caltech exploring the challenges of climate research and science as a human pursuit at Caltech’s Ramo Auditorium Nov. 1 to 3.
Artists’ collaborations with JPL and the display of their works at Glendale’s Brand Library were made possible by the generous support of the Glendale Arts and Culture Commission and the Glendale Library, Arts & Culture Trust.
More About JPL
A division of Caltech in Pasadena, California, JPL began in 1936 and ultimately built and helped launch America’s first satellite, Explorer 1, in 1958. By the end of that year, Congress established NASA and JPL became a part of the agency. Since then, JPL has managed such historic missions as Voyager, Galileo, Cassini, the Mars Exploration Rover program, the Perseverance Mars rover, and many more.
More About Glendale Library, Arts & Culture
Founded in 1907, the Glendale Library, Arts & Culture Department includes eight neighborhood libraries including the Brand Library & Art Center, a regional visual arts and music library and performance venue housed in the historic 1904 mansion of Glendale pioneer Leslie C. Brand, and the Central Library, a 93,000-square-foot center for individuals and groups to convene, collaborate, and create. The department also serves as the chief liaison to the Glendale Arts and Culture Commission which works to continually transform Glendale into an ever-evolving arts destination. Glendale Library Arts & Culture is supported in part through the efforts of the Glendale Library Arts & Culture Trust (GLACT). For more information visit GlendaleLAC.org, or contact Library, Arts & Culture at 818-548-2021 or via email at LibraryInfo@GlendaleCA.gov. Follow on Instagram, Facebook, and X at @MyGlendaleLAC.
For more information about PST ART: Art & Science Collide, visit: pst.art
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Preparations for Next Moonwalk Simulations Underway (and Underwater)
More than 100 scientists will participate in a field campaign involving a research vessel and two aircraft this month to verify the accuracy of data collected by NASA’s new PACE satellite: the Plankton, Aerosol, Cloud, ocean Ecosystem mission. The process of data validation includes researchers comparing PACE data with data collected by similar, Earth-based instruments to ensure the measurements match up. Since the mission’s Feb. 8, 2024 launch, scientists around the world have successfully completed several data validation campaigns; the September deployment — PACE-PAX — is its largest. From sea to sky to orbit, a range of vantage points allow NASA Earth scientists to collect different types of data to better understand our changing planet. Collecting them together, at the same place and the same time, is an important step used to verify the accuracy of satellite data.
NASA’s Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) satellite launched in February 2024 and is collecting observations of the ocean and measuring atmospheric particle and cloud properties. This data will help inform scientists and decision makers about the health of Earth’s ocean, land surfaces, and atmosphere and the interactions between them.
Technicians work to process the NASA’s Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) observatory on a spacecraft dolly in a high bay at the Astrotech Space Operations Facility near the agency’s Kennedy Space Center in Florida on Monday, Dec. 4, 2023. Credit: NASA/Kim Shiflett To make sure the data from PACE’s instruments accurately represent the ocean and the atmosphere, scientists compare (or “validate”) the data collected from orbit with measurements they collect at or near Earth’s surface. The mission’s biggest validation campaign, called PACE Postlaunch Airborne eXperiment (PACE-PAX), began on Sept. 3, 2024, and will last the entire month.
“If we want to have confidence in the observations from PACE, we need to validate those observations,” said Kirk Knobelspiesse, mission scientist for PACE-PAX and an atmospheric scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “This field campaign is focused on doing just that.”
Scientists will make measurements both from aircraft and ships. Based out of three locations across California — Marina, Santa Barbara, and NASA’s Armstrong Flight Research Center in Edwards — the campaign includes more than 100 people working in the field and several dozen instruments.
“This campaign allows us to validate data for both the atmosphere and the ocean, all in one campaign,” said Brian Cairns, deputy mission scientist for PACE-PAX and an atmospheric scientist at NASA’s Goddard Institute for Space Studies in New York City.
On the ocean, ships, including the National Oceanic and Atmospheric Administration (NOAA) research vessel Shearwater, will gather data on ocean biology and the optical properties of the water. Scientists onboard will gather water samples to help define the types of phytoplankton at different locations and their relative abundance, something that PACE’s hyperspectral Ocean Color Instrument measures from orbit.
Members of the PACE-PAX team – from left to right, Cecile Carlson, Adam Ahern (NOAA), Dennis Hamaker (NPS), Luke Ziemba, and Michael Shook (NASA Langley Research Center) – in front of the Twin Otter aircraft as they prep for the start of the campaign. Credit: Judy Alfter/NASA Overhead, a Twin Otter research aircraft operated by the Naval Postgraduate School in Monterey, California, will collect data on the atmosphere. At altitudes of up to 10,000 feet, the aircraft will sample and measure cloud droplet sizes, aerosol sizes, and the amount of light that those particles scatter and absorb. These are the atmospheric properties that PACE observes with its two polarimeters, SPEXOne and HARP2.
At a higher altitude — approximately 70,000 feet up — NASA’s ER-2 aircraft will provide a complementary view from above clouds, looking down on the atmosphere and ocean in finer detail than the satellite, but with a narrower view.
The NASA ER-2 high-altitude aircraft preparing for flight on Jan. 29, 2023. The aircraft is based at NASA’s Armstrong Flight Research Center Building 703 in Palmdale, California.Credit: NASA/Carla Thomas The plane will carry several instruments that are similar to those on PACE, including two prototypes of PACE’s polarimeters, called SPEXAirborne and AirHARP. In addition, two instruments called the Portable Remote Imaging SpectroMeter and Pushbroom Imager for Cloud and Aerosol Research and Development — from NASA’s Jet Propulsion Laboratory in Pasedena, California, and NASA’s Ames Research Center in California’s Silicon Valley, respectively — will measure essentially all the wavelengths of visible light (color). The remote sensing measurements are key for scientists who want to test the methods they use to analyze PACE satellite data.
Together, the instruments on the ER-2 approximate the data that PACE gathers and complement the in situ measurements from the ocean research vessel and the Twin Otter.
As the field campaign team gathers data, PACE will be observing the same areas of the ocean surface and atmosphere. Once the campaign is over, scientists will look at the data PACE returned and compare them to the measurements they took from the other three vantage points.
“Once you launch the satellite, there’s no more tinkering you can do,” said Ivona Cetinic, deputy mission scientist for PACE-PAX and an ocean scientist at NASA Goddard.
Though the scientists cannot alter the satellite anymore, the algorithms designed to interpret PACE data can be adjusted to make the measurements more accurate. Validation checks from campaigns like PACE-PAX help scientists ensure that PACE will be able to return accurate data about our oceans and atmosphere — critical to better understand our changing planet and its interconnected systems — for years to come.
“The ocean and atmosphere are such changing environments that it’s really important to validate what we see,” Cetinic said. “Understanding the accuracy of the view from the satellite is important, so we can use the data to answer important questions about climate change.”
By Erica McNamee
NASA’s Goddard Space Flight Center, Greenbelt, Md.
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Last Updated Sep 04, 2024 EditorKate D. RamsayerContactErica McNameeerica.s.mcnamee@nasa.govLocationGoddard Space Flight Center Related Terms
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NASA, ESA Missions Help Scientists Uncover How Solar Wind Gets Energy
Since the 1960s, astronomers have wondered how the Sun’s supersonic “solar wind,” a stream of energetic particles that flows out into the solar system, continues to receive energy once it leaves the Sun. Now, thanks to a lucky lineup of a NASA and an ESA (European Space Agency)/NASA spacecraft both currently studying the Sun, they may have discovered the answer — knowledge that is a crucial piece of the puzzle to help scientists better forecast solar activity between the Sun and Earth.
A paper published in the Aug. 30, 2024, issue of the journal Science provides persuasive evidence that the fastest solar winds are powered by magnetic “switchbacks,” or large kinks in the magnetic field, near the Sun.
“Our study addresses a huge open question about how the solar wind is energized and helps us understand how the Sun affects its environment and, ultimately, the Earth,” said Yeimy Rivera, co-leader of the study and a postdoctoral fellow at the Smithsonian Astrophysical Observatory, part of Center for Astrophysics | Harvard & Smithsonian. “If this process happens in our local star, it’s highly likely that this powers winds from other stars across the Milky Way galaxy and beyond and could have implications for the habitability of exoplanets.”
This artist’s concept shows switchbacks, or large kinks in the Sun’s magnetic field. NASA’s Goddard Space Flight Center/Conceptual Image Lab/Adriana Manrique Gutierrez Previously, NASA’s Parker Solar Probe found that these switchbacks were common throughout the solar wind. Parker, which became the first craft to enter the Sun’s magnetic atmosphere in 2021, allowed scientists to determine that switchbacks become more distinct and more powerful close to the Sun. Up to now, however, scientists lacked experimental evidence that this interesting phenomenon actually deposits enough energy to be important in the solar wind.
“About three years ago, I was giving a talk about how fascinating these waves are,” said co-author Mike Stevens, astrophysicist at the Center for Astrophysics. “At the end, an astronomy professor stood up and said, ‘that’s neat, but do they actually matter?’”
To answer this, the team of scientists had to use two different spacecraft. Parker is built to fly through the Sun’s atmosphere, or “corona.” ESA’s and NASA’s Solar Orbiter mission is also on an orbit that takes it relatively close to the Sun, and it measures solar wind at larger distances.
The discovery was made possible because of a coincidental alignment in February 2022 that allowed both Parker Solar Probe and Solar Orbiter to measure the same solar wind stream within two days of each other. Solar Orbiter was almost halfway to the Sun while Parker was skirting the edge of the Sun’s magnetic atmosphere.
This conceptual image shows Parker Solar Probe about to enter the solar corona. NASA/Johns Hopkins APL/Ben Smith An artist’s concept shows Solar Orbiter near the Sun. NASA’s Goddard Space Flight Center Conceptual Image Lab
“We didn’t initially realize that Parker and Solar Orbiter were measuring the same thing at all. Parker saw this slower plasma near the Sun that was full of switchback waves, and then Solar Orbiter recorded a fast stream which had received heat and with very little wave activity,” said Samuel Badman, astrophysicist at the Center for Astrophysics and the other co-lead of the study. “When we connected the two, that was a real eureka moment.”
Scientists have long known that energy is moved throughout the Sun‘s corona and the solar wind, at least in part, through what are known as “Alfvén waves.” These waves transport energy through a plasma, the superheated state of matter that makes up the solar wind.
However, how much the Alfvén waves evolve and interact with the solar wind between the Sun and Earth couldn’t be measured — until these two missions were sent closer to the Sun than ever before, at the same time. Now, scientists can directly determine how much energy is stored in the magnetic and velocity fluctuations of these waves near the corona, and how much less energy is carried by the waves farther from the Sun.
The new research shows that the Alfvén waves in the form of switchbacks provide enough energy to account for the heating and acceleration documented in the faster stream of the solar wind as it flows away from the Sun.
“It took over half a century to confirm that Alfvenic wave acceleration and heating are important processes, and they happen in approximately the way we think they do,” said John Belcher, emeritus professor from the Massachusetts Institute of Technology who co-discovered Alfvén waves in the solar wind but was not involved in this study.
In addition to helping scientists better forecast solar activity and space weather, such information helps us understand mysteries of the universe elsewhere and how Sun-like stars and stellar winds operate everywhere.
“This discovery is one of the key puzzle pieces to answer the 50-year-old question of how the solar wind is accelerated and heated in the innermost portions of the heliosphere, bringing us closer to closure to one of the main science objectives of the Parker Solar Probe mission,” said Adam Szabo, Parker Solar Probe mission science lead at NASA.
By Megan Watzke
Center for Astrophysics | Harvard & Smithsonian
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Last Updated Aug 30, 2024 Related Terms
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