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Supernova Survivor: First Supernova Companion Star Found
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By NASA
NASA/JPL-Caltech This Oct. 4, 2017, illustration shows a hypothetical uneven ring of dust orbiting KIC 8462852, also known as Boyajian’s Star or Tabby’s Star. The star has experienced unusual dips in brightness over a matter of days, as well as much subtler but longer-term dimming trends. Scientists proposed several explanations for this unexpected behavior, ranging from Tabby’s Star swallowing a planet to alien “megastructures” harvesting the star’s energy. However, a study using NASA’s Spitzer and Swift missions as well as the Belgian AstroLAB IRIS observatory suggests that the cause of the dimming over long periods is likely an uneven dust cloud moving around the star.
Learn more about this enigmatic star, named after Tabetha Boyajian, the Yale University postdoc who discovered it with the help of citizen scientists.
Image credit: NASA/JPL-Caltech
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By NASA
3 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
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A 3D simulation showing the evolution of turbulent flows in the upper layers of the Sun. The more saturated and bright reds represent the most vigorous upward or downward twisting motions. Clear areas represent areas where there is only relatively slow up-flows, with very little twisting.NASA/Irina Kitiashvili and Timothy A. Sandstrom NASA supercomputers are shedding light on what causes some of the Sun’s most complex behaviors. Using data from the suite of active Sun-watching spacecraft currently observing the star at the heart of our solar system, researchers can explore solar dynamics like never before.
The animation shows the strength of the turbulent motions of the Sun’s inner layers as materials twist into its atmosphere, resembling a roiling pot of boiling water or a flurry of schooling fish sending material bubbling up to the surface or diving it further down below.
“Our simulations use what we call a realistic approach, which means we include as much as we know to-date about solar plasma to reproduce different phenomena observed with NASA space missions,” said Irina Kitiashvili, a scientist at NASA’s Ames Research Center in California’s Silicon Valley who helped lead the study.
Using modern computational capabilities, the team was able, for the first time to reproduce the fine structures of the subsurface layer observed with NASA’s Solar Dynamics Observatory.
“Right now, we don’t have the computational capabilities to create realistic global models of the entire Sun due to the complexity,” said Kitiashvili. “Therefore, we create models of smaller areas or layers, which can show us structures of the solar surface and atmosphere – like shock waves or tornado-like features measuring only a few miles in size; that’s much finer detail than any one spacecraft can resolve.”
Scientists seek to better understand the Sun and what phenomena drive the patterns of its activity. The connection and interactions between the Sun and Earth drive the seasons, ocean currents, weather, climate, radiation belts, auroras and many other phenomena. Space weather predictions are critical for exploration of space, supporting the spacecraft and astronauts of NASA’s Artemis campaign. Surveying this space environment is a vital part of understanding and mitigating astronaut exposure to space radiation and keeping our spacecraft and instruments safe.
This has been a big year for our special star, studded with events like the annular eclipse, a total eclipse, and the Sun reaching its solar maximum period. In December 2024, NASA’s Parker Solar Probe mission – which is helping researchers to understand space weather right at the source – will make its closest-ever approach to the Sun and beat its own record of being the closest human-made object to reach the Sun.
The Sun keeps surprising us. We are looking forward to seeing what kind of exciting events will be organized by the Sun."
Irina Kitiashvili
NASA Scientist
“The Sun keeps surprising us,” said Kitiashvili. “We are looking forward to seeing what kind of exciting events will be organized by the Sun.”
These simulations were run on the Pleaides supercomputer at the NASA Advanced Supercomputing facility at NASA Ames over several weeks of runtime, generating terabytes of data.
NASA is showcasing 29 of the agency’s computational achievements at SC24, the international supercomputing conference, Nov. 17-22, 2023, in Atlanta, Georgia. For more technical information, visit:
https://www.nas.nasa.gov/sc24
For news media: Members of the news media interested in covering this topic should reach out to the NASA Ames newsroom.
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Last Updated Nov 21, 2024 Related Terms
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By NASA
Hubble Space Telescope Home NASA’s Hubble Finds… Hubble Space Telescope Hubble Home Overview About Hubble The History of Hubble Hubble Timeline Why Have a Telescope in Space? Hubble by the Numbers At the Museum FAQs Impact & Benefits Hubble’s Impact & Benefits Science Impacts Cultural Impact Technology Benefits Impact on Human Spaceflight Astro Community Impacts Science Hubble Science Science Themes Science Highlights Science Behind Discoveries Hubble’s Partners in Science Universe Uncovered Explore the Night Sky Observatory Hubble Observatory Hubble Design Mission Operations Missions to Hubble Hubble vs Webb Team Hubble Team Career Aspirations Hubble Astronauts News Hubble News Hubble News Archive Social Media Media Resources Multimedia Multimedia Images Videos Sonifications Podcasts E-books Lithographs Fact Sheets Glossary Posters Hubble on the NASA App More Online Activities 5 Min Read NASA’s Hubble Finds Sizzling Details About Young Star FU Orionis
An artist’s concept of the early stages of the young star FU Orionis (FU Ori) outburst, surrounded by a disk of material. Credits:
NASA-JPL, Caltech In 1936, astronomers saw a puzzling event in the constellation Orion: the young star FU Orionis (FU Ori) became a hundred times brighter in a matter of months. At its peak, FU Ori was intrinsically 100 times brighter than our Sun. Unlike an exploding star though, it has declined in luminosity only languidly since then.
Now, a team of astronomers has wielded NASA’s Hubble Space Telescope‘s ultraviolet capabilities to learn more about the interaction between FU Ori’s stellar surface and the accretion disk that has been dumping gas onto the growing star for nearly 90 years. They find that the inner disk touching the star is extraordinarily hot — which challenges conventional wisdom.
The observations were made with the telescope’s COS (Cosmic Origins Spectrograph) and STIS (Space Telescope Imaging Spectrograph) instruments. The data includes the first far-ultraviolet and new near-ultraviolet spectra of FU Ori.
“We were hoping to validate the hottest part of the accretion disk model, to determine its maximum temperature, by measuring closer to the inner edge of the accretion disk than ever before,” said Lynne Hillenbrand of Caltech in Pasadena, California, and a co-author of the paper. “I think there was some hope that we would see something extra, like the interface between the star and its disk, but we were certainly not expecting it. The fact we saw so much extra — it was much brighter in the ultraviolet than we predicted — that was the big surprise.”
A Better Understanding of Stellar Accretion
Originally deemed to be a unique case among stars, FU Ori exemplifies a class of young, eruptive stars that undergo dramatic changes in brightness. These objects are a subset of classical T Tauri stars, which are newly forming stars that are building up by accreting material from their disk and the surrounding nebula. In classical T Tauri stars, the disk does not touch the star directly because it is restricted by the outward pressure of the star’s magnetic field.
The accretion disks around FU Ori objects, however, are susceptible to instabilities due to their enormous mass relative to the central star, interactions with a binary companion, or infalling material. Such instability means the mass accretion rate can change dramatically. The increased pace disrupts the delicate balance between the stellar magnetic field and the inner edge of the disk, leading to material moving closer in and eventually touching the star’s surface.
This is an artist’s concept of the early stages of the young star FU Orionis (FU Ori) outburst, surrounded by a disk of material. A team of astronomers has used the Hubble Space Telescope’s ultraviolet capabilities to learn more about the interaction between FU Ori’s stellar surface and the accretion disk that has been dumping gas onto the growing star for nearly 90 years. They found that the inner disk, touching the star, is much hotter than expected—16,000 kelvins—nearly three times our Sun’s surface temperature. That sizzling temperature is nearly twice as hot as previously believed. NASA-JPL, Caltech
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The enhanced infall rate and proximity of the accretion disk to the star make FU Ori objects much brighter than a typical T Tauri star. In fact, during an outburst, the star itself is outshined by the disk. Furthermore, the disk material is orbiting rapidly as it approaches the star, much faster than the rotation rate of the stellar surface. This means that there should be a region where the disk impacts the star and the material slows down and heats up significantly.
“The Hubble data indicates a much hotter impact region than models have previously predicted,” said Adolfo Carvalho of Caltech and lead author of the study. “In FU Ori, the temperature is 16,000 kelvins [nearly three times our Sun’s surface temperature]. That sizzling temperature is almost twice the amount prior models have calculated. It challenges and encourages us to think of how such a jump in temperature can be explained.”
To address the significant difference in temperature between past models and the recent Hubble observations, the team offers a revised interpretation of the geometry within FU Ori’s inner region: The accretion disk’s material approaches the star and once it reaches the stellar surface, a hot shock is produced, which emits a lot of ultraviolet light.
Planet Survival Around FU Ori
Understanding the mechanisms of FU Ori’s rapid accretion process relates more broadly to ideas of planet formation and survival.
“Our revised model based on the Hubble data is not strictly bad news for planet evolution, it’s sort of a mixed bag,” explained Carvalho. “If the planet is far out in the disk as it’s forming, outbursts from an FU Ori object should influence what kind of chemicals the planet will ultimately inherit. But if a forming planet is very close to the star, then it’s a slightly different story. Within a couple outbursts, any planets that are forming very close to the star can rapidly move inward and eventually merge with it. You could lose, or at least completely fry, rocky planets forming close to such a star.”
Additional work with the Hubble UV observations is in progress. The team is carefully analyzing the various spectral emission lines from multiple elements present in the COS spectrum. This should provide further clues on FU Ori’s environment, such as the kinematics of inflowing and outflowing gas within the inner region.
“A lot of these young stars are spectroscopically very rich at far ultraviolet wavelengths,” reflected Hillenbrand. “A combination of Hubble, its size and wavelength coverage, as well as FU Ori’s fortunate circumstances, let us see further down into the engine of this fascinating star-type than ever before.”
These findings have been published in The Astrophysical Journal Letters.
The observations were taken as part of General Observer program 17176.
The Hubble Space Telescope has been operating for over three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space, based in Denver, also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.
Facebook logo @NASAHubble @NASAHubble Instagram logo @NASAHubble Media Contacts:
Claire Andreoli (claire.andreoli@nasa.gov)
NASA’s Goddard Space Flight Center, Greenbelt, MD
Abigail Major, Ray Villard
Space Telescope Science Institute, Baltimore, MD
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Last Updated Nov 21, 2024 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Related Terms
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By NASA
NASA/Ben Smegelsky & Virgil Cameron In this image from Aug. 26, 2023, participants from the 14th First Nations Launch High-Power Rocket Competition watch NASA’s SpaceX Crew-7 launch at the agency’s Kennedy Space Center in Florida. Students and advisors from University of Washington, University of Colorado-Boulder, and an international team from Queens University – the 2023 First Nations Launch grand prize teams – traveled to Kennedy for a VIP tour, culminating in viewing the Crew-7 launch.
Grand prize teams also went on a guided tour of historic Hangar AE, led by James Wood (Osage Nation and Loyal Shawnee), chief engineer of NASA’s Launch Services Program, technical advisor for the Crew-7 launch, and First Nations mentor and judge.
One of NASA’s Artemis Student Challenges, the First Nations Launch competition comprises students from tribal colleges and universities, Native American-Serving Nontribal Institutions, and collegiate chapters of the American Indian Science and Engineering Society who design, build, and launch a high-powered rocket from a launch site in Kansasville, Wisconsin.
Explore more Minority University Research and Education Project opportunities and resources here.
Image credit: NASA/Ben Smegelsky & Virgil Cameron
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By NASA
Dr. Annie Meier (second from left) and her team inside the Applied Chemistry Lab at NASA’s Kennedy Space Center in Florida began supplementing their normal workload in mid-2023 with efforts to improve the lab’s sustainable practices. In 2024, the laboratory became the first at NASA to receive certification from the non-profit My Green Lab for its efforts in sustainability.NASA/Kim Shiflett NASA’s Kennedy Space Center in Florida has a long record of achievements in sustainability and recently added another to the list when the spaceport’s Applied Chemistry Lab became the first in the agency to be certified for its environmentally conscious practices.
The My Green Lab Certification recognizes sustainability best practices in research facilities around the world. The certification program run by My Green Lab, a non-profit dedicated to creating a culture of sustainability through science, is considered a key measure of progress towards a zero-carbon future by the United Nations Race to Zero campaign.
“When I heard our lab achieved certification, I was so happy,” said Dr. Annie Meier, one of the laboratory’s chemical engineers. “It meant we could now make a conscious effort to share these green practices with all who work in our lab. We even added them to our training materials for new and incoming members in the lab.”
The lab performs research and technology development for a wide range of chemistry and engineering-related applications to solve the unique operational needs of NASA and outside partners. The lab primarily focuses on in-situ resource utilization and addressing technology gaps related to lunar and Martian sustainability. The lab’s scientists also provide expertise in the fields of logistics reduction, plasma science, hypergolic fuels, analytical instrumentation, and gas analysis.
While sustainability has long been a focus of the lab, the journey to the certification began when Riley Yager, a doctoral student from University of Alabama at Birmingham – where Meier was a technical monitor – shared her knowledge of the program after pursuing green lab practices at her university.
“I work as a sustainability ambassador at my university, so I knew of this program,” Yager said. “Sustainable practices are something woven into my everyday life, so naturally I wanted to bring those practices into my lab environments.”
After learning about the program from Yager and discovering the many other academic institutions and companies certified globally, Meier submitted a proposal to NASA and obtained funding to pursue certification for the Applied Chemistry Lab.
After a kickoff event hosted by My Green Lab in April 2023, the lab’s path to certification began with a self-assessment survey, in which members of the lab answered a series of questions about their practices in areas such as cold storage, green chemistry, infrastructure energy, resource management, waste reduction, and water. My Green Lab collected and analyzed the answers, providing a baseline assessment and recommendations to improve the lab’s sustainable practices.
“We took their initial survey and learned we had lots of room for improvements as a lab,” Meier said. “Then I worked with a few interns over the summer to spearhead the ‘green team’ to implement changes and get momentum from the entire lab.”
The lab began with minimizing purchases by improving efficiencies during the inventory process. The team also performed a waste audit of all seven of its laboratories. They adopted nitrile glove and pipette tip box recycling, reviewed the “12 principles of green chemistry” with the lab members, and installed stickers and signage about what can and cannot be unplugged to save energy. Additionally, they installed low-flow aerators on the lab tap sinks to reduce flow, and the lab now uses a recycling sink to save on water or solvents for cleaning parts.
As luck would have it, Yager ended up working at the Applied Chemistry Lab on a NASA fellowship and became a member of the green team.
“It was really fun to see that come full circle,” Meier said. “Almost all members of the lab, from our fellows to most senior members, used their self-motivation to get on the sustainability train.”
The green team continued to grow as the lab implemented changes to become more sustainable. Just over six months after the kickoff event, they completed another assessment survey. With possible certification levels of bronze, silver, gold, platinum, and green – the level that adheres closest to My Green Lab’s highest standards – the ACL was certified green, marking the first time any NASA center obtained a My Green Lab Certification.
“Our lab is looking to sustain these green practices and achieve the same status when we are reassessed in the future,” Meier said. “This effort could be a wonderful catalyst to inspire other work groups to lean towards more ‘green’ practices at the frontline in our laboratories.”
The NASA Kennedy lab joined over 2,500 labs in a range of sectors that received the My Green Lab certification. Maintaining the distinction will require recertification every two years.
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