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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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Hubble Space Telescope
Since its 1990 launch, the Hubble Space Telescope has changed our fundamental understanding of the universe.
Exploring the Birth of Stars
Hubble’s Night Sky Challenge
Hubble Focus: The Lives of Stars
This e-book highlights the mission’s recent discoveries and observations related to the birth, evolution, and death of stars.
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By NASA
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Preparations for Next Moonwalk Simulations Underway (and Underwater)
Hundreds of students, scientists, and other stakeholders listen in person and online as NASA leaders discuss the Artemis missions during the 2023 von Braun Space Exploration Symposium held Oct. 25–27 at the University of Alabama in Huntsville. NASA / Charles Beason Media are invited to attend the 2024 von Braun Space Exploration Symposium Monday Oct. 28 to Wednesday, Oct. 30 at the University of Alabama in Huntsville.
Organized by the American Astronautical Society in collaboration with NASA’s Marshall Space Flight Center in Huntsville, the annual symposium gathers leaders from across government, industry, policy, and academia to discuss the current landscape of space exploration and chart a path forward amid the challenges that lie ahead.
The theme of this year’s event is “Expanding Exploration: From Vision to Reality,” focusing on NASA’s and Marshall’s plans for the future and the broader discourse about exploration and discovery, technology, the workforce, and other elements of the space ecosystem.
Media members interested should register with the astronautical society as a media representative under these guidelines for in-person or online attendance.
Marshall Center Director Joseph Pelfrey will deliver opening remarks on Oct. 28, followed by panels on Artemis, artificial intelligence, and workforce development. NASA Deputy Associate Administrator Casey Swails will deliver a keynote address to close out the first day.
Panels on, Oct. 29, will focus on space nuclear propulsion, science, and lunar logistics and mobility. Col. Eric Zarybnisky, Office of Space Launch director at the National Reconnaissance Office, will provide the luncheon keynote.
The third and final day of the symposium Oct. 30, will include discussions on nuclear propulsion, space technology, and human exploration beyond low-Earth orbit. NASA Associate Administrator Jim Free and Wayne Hale, who retired in 2010 as the deputy associate administrator of strategic partnerships at NASA Headquarters in Washington, will lead a discussion and present awards at the closing luncheon.
To arrange interviews with NASA Marshall speakers, contact Hannah Maginot, 256-932-1937, or Molly Porter, 256-424-5158.
For more information on NASA’s Marshall Space Flight Center, visit:
https://www.nasa.gov/marshall
Hannah Maginot
Marshall Space Flight Center, Huntsville, Ala.
hannah.l.maginot@nasa.gov
256-932-1937
Molly Porter
Marshall Space Flight Center, Huntsville, Ala.
molly.a.porter@nasa.gov
256-424-5158
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Last Updated Oct 23, 2024 EditorBeth RidgewayContactMolly Portermolly.a.porter@nasa.govLocationMarshall Space Flight Center Related Terms
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19 min read The Marshall Star for October 23, 2024
Article 1 hour ago 4 min read NASA Begins New Deployable Solar Array Tech Demo on Pathfinder Spacecraft
Article 5 hours ago 5 min read NASA’s IXPE Helps Researchers Determine Shape of Black Hole Corona
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By NASA
Representatives of the Artemis Accords signatories, including NASA leadership, met Oct. 14, 2024, for a principals meeting in Milan, during the International Astronautical Congress. With 42 of 45 signatories participating in the event, established and emerging spacefaring nations from every region of the world were represented. Credit: UAE Space Agency A record number of Artemis Accords signatories, including the United States, gathered at the International Astronautical Congress (IAC), the world’s largest global space conference taking place in Milan this week, furthering discussions on the safe and responsible use of space for the benefit of all.
During the space conference, top space agency leaders and other government representatives met Oct. 14 to continue advancing implementation of the Artemis Accords, marking the most comprehensive engagement yet among Accords signatories.
“As we send humans further into the solar system, collaboration and shared responsibility among nations are more critical than ever,” said NASA Deputy Administrator Pam Melroy. “The Artemis Accords provide a common sense set of principles to guide our work together, and our recent efforts to further their implementation is fostering a remarkable environment of trust and cooperation where all nations can contribute to and benefit from these endeavors.”
The high-level meeting was co-chaired by NASA, CSA (Canadian Space Agency) and Italian Space Agency. With 42 of 45 signatories participating, established and emerging spacefaring nations from every region of the world were represented to help create a foundation for future space exploration for the Artemis Generation.
Leaders from each nation reflected on how the group can contribute to and advance existing multilateral forums, further technical discussions to inform policy deliberations, and promote and encourage the participation of emerging space nations including the adoption of the Artemis Accords by additional countries. They agreed on recommendations on non-interference, interoperability, release of scientific data, long-term sustainability guidelines, and registration to advance implementing the Artemis Accords. A method of operations was established for the ongoing work of the signatories.
“Promoting the participation of emerging space nations and encouraging the adoption of the Artemis Accords is crucial for the entire space,” said Teodoro Valente, president of the Italian Space Agency. “This is a matter of strategic importance in order to ensure the active and meaningful engagement of emerging space nations, both those already part of the Artemis Accords, and those poised to join in the future.”
The conversation in Milan built on previous work during a workshop in Montreal in May 2024, where participantsdelved into the topics such as non-interference and interoperability.
“Canada is pleased to be part of a growing group of countries committed to the safety and sustainability of outer space activities,” said Lisa Campbell, CSA president. “We are strong supporters of the Artemis Accords and are pleased to have hosted the most recent workshop that advanced work on key aspects of the Artemis Accords. We look forward to continuing this important work in the coming months and years.”
In October 2023, signatories agreed on an initial set of mission data parameters to advance transparency and non-interference in conducting space activities. The data parameters identify relevant information about planned lunar surface missions including expected launch dates, the general nature of activities, and landing locations. Recent progress also included work on a database to house them. Several space agencies, including NASA, have submitted mission data to the United Nations Office of Outer Space Affairs for dissemination.
Potential focus areas for the next year include further advancing sustainability, including debris management for both lunar orbit and the surface of the Moon.
In 2020, the United States and seven other nations were the first to sign the Artemis Accords, which identified a set of principles promoting the beneficial use of space for humanity. The Artemis Accords are grounded in the Outer Space Treaty and other agreements including the Registration Convention, the Rescue and Return Agreement, as well as best practices and norms of responsible behavior that NASA and its partners have supported, including the public release of scientific data.
The commitments of the Artemis Accords and efforts by the signatories to advance implementation of these principles support the safe and sustainable exploration of space.
Learn more about the Artemis Accords at:
https://www.nasa.gov/artemis-accords
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Amber Jacobson / Elizabeth Shaw
Headquarters, Washington
202-358-1600
amber.c.jacobson@nasa.gov / elizabeth.a.shaw@nasa.gov
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Last Updated Oct 18, 2024 LocationNASA Headquarters Related Terms
artemis accords Opportunities For International Participants to Get Involved Science of Space Exploration View the full article
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By European Space Agency
Imagine a near future where services such as satellite navigation, video conferencing, and file sharing are as seamless on the Moon as they are on Earth.
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By NASA
Hubble Space Telescope Home NASA’s Hubble Finds that… Missions 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 6 min read
NASA’s Hubble Finds that a Black Hole Beam Promotes Stellar Eruptions
This is an artist’s concept looking down into the core of the giant elliptical galaxy M87. A supermassive black hole ejects a 3,000-light-year-long jet of plasma, traveling at nearly the speed of light. In the foreground, to the right is a binary star system. The system is far from the black hole, but in the vicinity of the jet. In the system an aging, swelled-up, normal star spills hydrogen onto a burned-out white dwarf companion star. As the hydrogen accumulates on the surface of the dwarf, it reaches a tipping point where it explodes like a hydrogen bomb. Novae frequently pop-off throughout the giant galaxy of 1 trillion stars, but those near the jet seem to explode more frequently. So far, it’s anybody’s guess why black hole jets enhance the rate of nova eruptions. NASA, ESA, Joseph Olmsted (STScI)
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In a surprise finding, astronomers using NASA’s Hubble Space Telescope have discovered that the blowtorch-like jet from a supermassive black hole at the core of a huge galaxy seems to cause stars to erupt along its trajectory. The stars, called novae, are not caught inside the jet, but apparently in a dangerous neighborhood nearby.
The finding is confounding researchers searching for an explanation. “We don’t know what’s going on, but it’s just a very exciting finding,” said lead author Alec Lessing of Stanford University. “This means there’s something missing from our understanding of how black hole jets interact with their surroundings.”
A nova erupts in a double-star system where an aging, swelled-up, normal star spills hydrogen onto a burned-out white dwarf companion star. When the dwarf has tanked up a mile-deep surface layer of hydrogen that layer explodes like a giant nuclear bomb. The white dwarf isn’t destroyed by the nova eruption, which ejects its surface layer and then goes back to siphoning fuel from its companion, and the nova-outburst cycle starts over again.
Hubble found twice as many novae going off near the jet as elsewhere in the giant galaxy during the surveyed time period. The jet is launched by a 6.5-billion-solar-mass central black hole surrounded by a disk of swirling matter. The black hole, engorged with infalling matter, launches a 3,000-light-year-long jet of plasma blazing through space at nearly the speed of light. Anything caught in the energetic beam would be sizzled. But being near its blistering outflow is apparently also risky, according to the new Hubble findings.
A Hubble Space Telescope image of the giant galaxy M87 shows a 3,000-light-year-long jet of plasma blasting from the galaxy’s 6.5-billion-solar-mass central black hole. The blowtorch-like jet seems to cause stars to erupt along its trajectory. These novae are not caught inside the jet, but are apparently in a dangerous neighborhood nearby. During a recent 9-month survey, astronomers using Hubble found twice as many of these novae going off near the jet as elsewhere in the galaxy. The galaxy is the home of several trillion stars and thousands of star-like globular star clusters. NASA, ESA, STScI, Alec Lessing (Stanford University), Mike Shara (AMNH); Acknowledgment: Edward Baltz (Stanford University); Image Processing: Joseph DePasquale (STScI)
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The finding of twice as many novae near the jet implies that there are twice as many nova-forming double-star systems near the jet or that these systems erupt twice as often as similar systems elsewhere in the galaxy.
“There’s something that the jet is doing to the star systems that wander into the surrounding neighborhood. Maybe the jet somehow snowplows hydrogen fuel onto the white dwarfs, causing them to erupt more frequently,” said Lessing. “But it’s not clear that it’s a physical pushing. It could be the effect of the pressure of the light emanating from the jet. When you deliver hydrogen faster, you get eruptions faster. Something might be doubling the mass transfer rate onto the white dwarfs near the jet.” Another idea the researchers considered is that the jet is heating the dwarf’s companion star, causing it to overflow further and dump more hydrogen onto the dwarf. However, the researchers calculated that this heating is not nearly large enough to have this effect.
“We’re not the first people who’ve said that it looks like there’s more activity going on around the M87 jet,” said co-investigator Michael Shara of the American Museum of Natural History in New York City. “But Hubble has shown this enhanced activity with far more examples and statistical significance than we ever had before.”
Shortly after Hubble’s launch in 1990, astronomers used its first-generation Faint Object Camera (FOC) to peer into the center of M87 where the monster black hole lurks. They noted that unusual things were happening around the black hole. Almost every time Hubble looked, astronomers saw bluish “transient events” that could be evidence for novae popping off like camera flashes from nearby paparazzi. But the FOC’s view was so narrow that Hubble astronomers couldn’t look away from the jet to compare with the near-jet region. For over two decades, the results remained mysteriously tantalizing.
Compelling evidence for the jet’s influence on the stars of the host galaxy was collected over a nine-month interval of Hubble observing with newer, wider-view cameras to count the erupting novae. This was a challenge for the telescope’s observing schedule because it required revisiting M87 precisely every five days for another snapshot. Adding up all of the M87 images led to the deepest images of M87 that have ever been taken.
In a surprise finding, astronomers, using NASA’s Hubble Space Telescope have discovered that the jet from a supermassive black hole at the core of M87, a huge galaxy 54 million light years away, seems to cause stars to erupt along its trajectory.
NASA’s Goddard Space Flight Center; Lead Producer: Paul Morris Hubble found 94 novae in the one-third of M87 that its camera can encompass. “The jet was not the only thing that we were looking at — we were looking at the entire inner galaxy. Once you plotted all known novae on top of M87 you didn’t need statistics to convince yourself that there is an excess of novae along the jet. This is not rocket science. We made the discovery simply by looking at the images. And while we were really surprised, our statistical analyses of the data confirmed what we clearly saw,” said Shara.
This accomplishment is entirely due to Hubble’s unique capabilities. Ground-based telescope images do not have the clarity to see novae deep inside M87. They cannot resolve stars or stellar eruptions close to the galaxy’s core because the black hole’s surroundings are far too bright. Only Hubble can detect novae against the bright M87 background.
Novae are remarkably common in the universe. One nova erupts somewhere in M87 every day. But since there are at least 100 billion galaxies throughout the visible universe, around 1 million novae erupt every second somewhere out there.
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, Colorado, also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, Maryland, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.
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Hubble’s Messier Catalog: M87
Hubble Black Holes
Monster Black Holes are Everywhere
Facebook logo @NASAHubble @NASAHubble Instagram logo @NASAHubble Media Contact:
Claire Andreoli
NASA’s Goddard Space Flight Center, Greenbelt, MD
claire.andreoli@nasa.gov
Ray Villard
Space Telescope Science Institute, Baltimore, MD
Science Contact:
Alec Lessing
Stanford University, Stanford, CA
Michael Shara
American Museum of Natural History, New York, NY
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Last Updated Sep 26, 2024 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Related Terms
Astrophysics Astrophysics Division Black Holes Goddard Space Flight Center Hubble Space Telescope Missions Stars The Universe Keep Exploring Discover More Topics From Hubble
Hubble Space Telescope
Since its 1990 launch, the Hubble Space Telescope has changed our fundamental understanding of the universe.
Hubble E-books
Hubble’s Messier Catalog
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