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By Space Force
SecAF Kendall delivered a speech to USAFA cadets about the qualities necessary for strong leadership and why capable, insightful, moral leaders are more essential than ever in defense of the nation.
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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
Astrophysics Astrophysics Division Goddard Space Flight Center Hubble Space Telescope Stars 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.
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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The guitar shape in the “Guitar Nebula” comes from bubbles blown by particles ejected from the pulsar through a steady wind as it moves through space. A movie of Chandra (red) data taken in 2000, 2006, 2012, and 2021 has been combined with a single image in optical light from Palomar. X-rays from Chandra show a filament of energetic matter and antimatter particles, about two light-years long, blasting away from the pulsar (seen as the bright white dot). The movie shows how this filament has changed over two decades. X-ray: NASA/CXC/Stanford Univ./M. de Vries et al.; Optical full field: Palomar Obs./Caltech & inset: NASA/ESA/STScI; Image Processing: NASA/CXC/SAO/L. Frattare) Normally found only in heavy metal bands or certain post-apocalyptic films, a “flame-throwing guitar” has now been spotted moving through space. Astronomers have captured movies of this extreme cosmic object using NASA’s Chandra X-ray Observatory and Hubble Space Telescope.
The new movie of Chandra (red) and Palomar (blue) data helps break down what is playing out in the Guitar Nebula. X-rays from Chandra show a filament of energetic matter and antimatter particles, about two light-years or 12 trillion miles long, blasting away from the pulsar (seen as the bright white dot connected to the filament).
Astronomers have nicknamed the structure connected to the pulsar PSR B2224+65 as the “Guitar Nebula” because of its distinct resemblance to the instrument in glowing hydrogen light. The guitar shape comes from bubbles blown by particles ejected from the pulsar through a steady wind. Because the pulsar is moving from the lower right to the upper left, most of the bubbles were created in the past as the pulsar moved through a medium with variations in density.
X-ray: NASA/CXC/Stanford Univ./M. de Vries et al.; Optical: (Hubble) NASA/ESA/STScI and (Palomar) Hale Telescope/Palomar/CalTech; Image Processing: NASA/CXC/SAO/L. Frattare At the tip of the guitar is the pulsar, a rapidly rotating neutron star left behind after the collapse of a massive star. As it hurtles through space it is pumping out a flame-like filament of particles and X-ray light that astronomers have captured with Chandra.
How does space produce something so bizarre? The combination of two extremes — fast rotation and high magnetic fields of pulsars — leads to particle acceleration and high-energy radiation that creates matter and antimatter particles, as electron and positron pairs. In this situation, the usual process of converting mass into energy, famously determined by Albert Einstein’s E = mc2 equation, is reversed. Here, energy is being converted into mass to produce the particles.
Particles spiraling along magnetic field lines around the pulsar create the X-rays that Chandra detects. As the pulsar and its surrounding nebula of energetic particles have flown through space, they have collided with denser regions of gas. This allows the most energetic particles to escape the confines of the Guitar Nebula and fly to the right of the pulsar, creating the filament of X-rays. When those particles escape, they spiral around and flow along magnetic field lines in the interstellar medium, that is, the space in between stars.
The new movie shows the pulsar and the filament flying towards the upper left of the image through Chandra data taken in 2000, 2006, 2012 and 2021. The movie has the same optical image in each frame, so it does not show changes in parts of the “guitar.” A separate movie obtained with data from NASA’s Hubble Space Telescope (obtained in 1994, 2001, 2006, and 2021) shows the motion of the pulsar and the smaller structures around it.
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Hubble Space Telescope data: 1994, 2001, 2006, and 2021.X-ray: NASA/CXC/Stanford Univ./M. de Vries et al.; Optical full field: Palomar Obs./Caltech & inset: NASA/ESA/STScI; Image Processing: NASA/CXC/SAO/L. Frattare) A study of this data has concluded that the variations that drive the formation of bubbles in the hydrogen nebula, which forms the outline of the guitar, also control changes in how many particles escape to the right of the pulsar, causing subtle brightening and fading of the X-ray filament, like a cosmic blow torch shooting from the tip of the guitar.
The structure of the filament teaches astronomers about how electrons and positrons travel through the interstellar medium. It also provides an example of how this process is injecting electrons and positrons into the interstellar medium.
A paper describing these results was published in The Astrophysical Journal and is available here.
NASA’s Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.
Read more from NASA’s Chandra X-ray Observatory.
Learn more about the Chandra X-ray Observatory and its mission here:
https://www.nasa.gov/chandra
https://chandra.si.edu
Visual Description:
This release features two short videos and a labeled composite image, all featuring what can be described as a giant flame-throwing guitar floating in space.
In both the six second multiwavelength Guitar Nebula timelapse video and the composite image, the guitar shape appears at our lower left, with the neck of the instrument pointing toward our upper left. The guitar shape is ghostly and translucent, resembling a wispy cloud on a dark night. At the end of the neck, the guitar’s headstock comes to a sharp point that lands on a bright white dot. This dot is a pulsar, and the guitar shape is a hydrogen nebula. The nebula was formed when particles being ejected by the pulsar produced a cloud of bubbles. The bubbles were then blown into a curvy guitar shape by a steady wind. The guitar shape is undeniable, and is traced by a thin white line in the labeled composite image.
The pulsar, known as PSR B2224+65, has also released a long filament of energetic matter and antimatter particles approximately 12 trillion miles long. In both the composite image and the six second video, this energetic, X-ray blast shoots from the bright white dot at the tip of the guitar’s headstock, all the way out to our upper righthand corner. In the still image, the blast resembles a streak of red dots, most of which fall in a straight, densely packed line. The six second video features four separate images of the phenomenon, created with Chandra data gathered in 2000, 2006, 2012, and 2021. When shown in sequence, the density of the X-ray blast filament appears to fluctuate.
A 12 second video is also included in this release. It features four images that focus on the headstock of the guitar shape. These images were captured by the Hubble Space Telescope in 1994, 2001, 2006, and 2021. When played in sequence, the images show the headstock shape expanding. A study of this data has concluded that the variations that drive the formation of bubbles in the hydrogen nebula also control changes in the pulsar’s blast filament. Meaning the same phenomenon that created the cosmic guitar also created the cosmic blowtorch shooting from the headstock.
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By NASA
Artist’s concept of a young, newly discovered planet, exposed to observation by a warped debris disk. Credit: Robert Hurt, Caltech-IPAC. The discovery
A huge planet with a long name – IRAS 04125+2902 b – is really just a baby: only 3 million years old. And because such infant worlds are usually hidden inside obscuring disks of debris, it is the youngest planet so far discovered using the dominant method of planet detection.
Key facts
The massive planet, likely still glowing from the heat of its formation, lies in the Taurus Molecular Cloud, an active stellar nursery with hundreds of newborn stars some 430 light-years away. The cloud’s relative closeness makes it a prime target for astronomers. But while the cloud offers deep insight into the formation and evolution of young stars, their planets are usually a closed book to telescopes like TESS, the Transiting Exoplanet Survey Satellite. These telescopes rely on the “transit method,” watching for the slight dip in starlight when a planet crosses the face of its host star. But such planetary systems must be edge-on, from Earth’s vantage point, for the transit method to work. Very young star systems are surrounded by disks of debris, however, blocking our view of any potentially transiting planets.
A research team has just reported an extraordinary stroke of luck. Somehow, the outer debris disk surrounding this newborn planet, IRAS 04125+2902 b, has been sharply warped, exposing the baby world to extensive transit observations by TESS.
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While the warped outer disk is a great coincidence, it’s also a great mystery. Possible explanations include a migration of the planet itself, moving closer to the star and, in the process, diverging from the orientation of the outer disk – so that, from Earth, the planet’s orbit is edge-on, crossing the face of the star, but the outer disk remains nearly face-on to us. One problem with this idea: Moving a planet so far out of alignment with its parent disk would likely require another (very large) object in this system. None has been detected so far.
The system’s sun happens to have a distant stellar companion, also a possible culprit in the warping of the outer disk. The angle of the orbit of the companion star, however, matches that of the planet and its parent star. Stars and planets tend to take the gravitational path of least resistance, so such an arrangement should push the disk into a closer alignment with the rest of the system – not into a radical departure.
Another way to get a “broken” outer disk, the study authors say, would not involve a companion star at all. Stellar nurseries like the Taurus Molecular Cloud can be densely packed, busy places. Computer simulations show that rains of infalling material from the surrounding star-forming region could be the cause of disk-warping. Neither simulations nor observations have so far settled the question of whether warped or broken disks are common or rare in such regions.
Fun facts
Combining TESS’s transit measurements with another way of observing planets yields more information about the planet itself. We might call this second approach the “wobble” method. The gravity of a planet tugs its star one way, then another, as the orbiting planet makes its way around the star. And that wobble can be detected by changes in the light from the star, picked up by specialized instruments on Earth. Such “radial velocity” measurements of this planet reveal that its mass, or heft, amounts to no more than about a third of our own Jupiter. But the transit data shows the planet’s diameter is about the same. That means the planet has a comparatively low density and, likely, an inflated atmosphere. So this world probably is not a gas giant like Jupiter. Instead, it could well be a planet whose atmosphere will shrink over time. When it finally settles down, it could become a gaseous “mini-Neptune” or even a rocky “super-Earth.” These are the two most common planet types in our galaxy – despite the fact that neither type can be found in our solar system.
The discoverers
A science team led by astronomer Madyson G. Barber of the University of North Carolina at Chapel Hill published the study, “A giant planet transiting a 3 Myr protostar with a misaligned disk,” in the journal Nature in November 2024.
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By NASA
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5 Surprising NASA Heliophysics Discoveries Not Related to the Sun
With NASA’s fleet of heliophysics spacecraft, scientists monitor our Sun and investigate its influences throughout the solar system. However, the fleet’s constant watch and often-unique perspectives sometimes create opportunities to make discoveries that no one expected, helping us to solve mysteries about of the solar system and beyond.
Here are five examples of breakthroughs made by NASA heliophysics missions in other fields of science.
This graphic shows missions in NASA’s Heliophysics Division fleet as of July 2024. NASA Thousands and Thousands of Comets
The SOHO mission — short for Solar and Heliospheric Observatory, which is a joint mission between ESA (European Space Agency) and NASA — has a coronagraph that blocks out the Sun in order to see the Sun’s faint outer atmosphere, or corona.
It turns out SOHO’s coronagraph also makes it easy to spot sungrazing comets, those that pass so close to the Sun that other observatories can’t see them against the brightness of our star.
Before SOHO was launched in December 1995, fewer than 20 sungrazing comets were known. Since then, SOHO has discovered more than 5,000.
The vast number of comets discovered using SOHO has allowed scientists to learn more about sungrazing comets and identify comet families, descended from ancestor comets that broke up long ago.
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Two sungrazing comets fly close to the Sun in these images captured by ESA/NASA’s SOHO (Solar and Heliospheric Observatory). They were the 3,999th and 4,000th comets discovered in SOHO images. ESA/NASA/SOHO/Karl Battams Dimming of a Supergiant
In late 2019, the supergiant star Betelgeuse began dimming unexpectedly. Telescopes all over the world — and around it — tracked these changes until a few months later when Betelgeuse appeared too close to the Sun to observe. That’s when NASA’s STEREO (Sun-watching Solar Terrestrial Relations Observatory (STEREO) came to the rescue.
For several weeks in the middle of 2020, STEREO was the only observatory able to see Betelgeuse. At the time, the STEREO-A spacecraft was trailing behind Earth, at a vantage point where Betelgeuse was still far enough away from the Sun to be seen. This allowed astronomers to keep tabs on the star while it was out of view from Earth.
STEREO’s observations revealed another unexpected dimming between June and August of 2020, when ground-based telescopes couldn’t view the star.
Astronomers later concluded that these dimming episodes were caused by an ejection of mass from Betelgeuse — like a coronal mass ejection from our Sun but with about 400 times more mass — which obscured part of the star’s bright surface.
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The background image shows the star Betelgeuse as seen by the Heliospheric Imager aboard NASA’s STEREO (Solar Terrestrial Relations Observatory) spacecraft. The inset figure shows measurements of Betelgeuse’s brightness taken by different observatories from late 2018 to late 2020. STEREO’s observations, marked in red, revealed an unexpected dimming in mid-2020 when Betelgeuse appeared too close to the Sun for other observatories to view it. NASA/STEREO/HI (background); Dupree et al. (inset) The Glowing Surface of Venus
NASA’s Parker Solar Probe studies the Sun’s corona up close — by flying through it. To dive into the Sun’s outer atmosphere, the spacecraft has flown past Venus several times, using the planet’s gravity to fling itself closer and closer to the Sun.
On July 11, 2020, during Parker’s third Venus flyby, scientists used Parker’s wide-field imager, called WISPR, to try to measure the speed of the clouds that obscure Venus’ surface. Surprisingly, WISPR not only observed the clouds, it also saw through them to the surface below.
The images from that flyby and the next (in 2021) revealed a faint glow from Venus’ hot surface in near-infrared light and long wavelengths of red (visible) light that maps distinctive features like mountainous regions, plains, and plateaus.
Scientists aimed WISPR at Venus again on Nov. 6, 2024, during Parker’s seventh flyby, observing a different part of the planet than previous flybys. With these images, they’re hoping to learn more about Venus’ surface geology, mineralogy, and evolution.
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As Parker Solar Probe flew by Venus on its fourth flyby, it captured these images, strung into a video, showing bright and dark features on the nightside surface of the planet. NASA/APL/NRL The Brightest Gamma-Ray Burst
You’ve heard of the GOAT. But have you heard of the BOAT?
It stands for the “brightest of all time”, a gamma-ray burst discovered on Oct. 9, 2022.
A gamma-ray burst is a brief but intense eruption of gamma rays in space, lasting from seconds to hours.
This one, named GRB 221009A, glowed brilliantly for about 10 minutes in the constellation Sagitta before slowly fading.
The burst was detected by dozens of spacecraft, including NASA’s Wind, which studies the perpetual flow of particles from the Sun, called the solar wind, just before it reaches Earth.
Wind and NASA’s Fermi Gamma-Ray Space Telescope measured the brightness of GRB 221009A, showing that it was 70 times brighter than any other gamma-ray burst ever recorded by humans — solidifying its status as the BOAT.
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Astronomers think GRB 221009A represents the birth of a new black hole formed within the heart of a collapsing star. In this artist’s concept, the black hole drives powerful jets of particles traveling near the speed of light. The jets emit X-rays and gamma rays as they stream into space. NASA/Swift/Cruz deWilde A Volcano Blasts Its Way to Space
NASA’s ICON (Ionospheric Connection Explorer) launched in 2019 to study how Earth’s weather interacts with weather from space. When the underwater Hunga Tonga-Hunga Ha‘apai volcano erupted on Jan. 15, 2022, ICON helped show that the volcano produced more than ash and tsunami waves — its effects reached the edge of space.
In the hours after the eruption, ICON detected hurricane-speed winds in the ionosphere — Earth’s electrified upper atmospheric layer at the edge of space. ICON clocked the wind speeds at up to 450 miles per hour, making them the strongest winds the mission had ever measured below 120 miles altitude.
The ESA Swarm mission revealed that these extreme winds altered an electric current in the ionosphere called the equatorial electrojet. After the eruption, the equatorial electrojet surged to five times its normal peak power and dramatically flipped direction.
Scientists were surprised that a volcano could affect the electrojet so severely — something they’d only seen during a strong geomagnetic storm caused by an eruption from the Sun.
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The Hunga Tonga-Hunga Ha’apai eruption on Jan. 15, 2022, caused many effects, some illustrated here, that were felt around the world and even into space. Some of those effects, like extreme winds and unusual electric currents were picked up by NASA’s ICON (Ionospheric Connection Explorer) mission and ESA’s (the European Space Agency) Swarm. Illustration is not to scale. NASA’s Goddard Space Flight Center/Mary Pat Hrybyk-Keith By Vanessa Thomas
NASA’s Goddard Space Flight Center, Greenbelt, Md.
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Last Updated Nov 20, 2024 Related Terms
Comets Fermi Gamma-Ray Space Telescope Gamma-Ray Bursts Goddard Space Flight Center Heliophysics Heliophysics Division ICON (Ionospheric Connection Explorer) Parker Solar Probe (PSP) SOHO (Solar and Heliospheric Observatory) Stars STEREO (Solar TErrestrial RElations Observatory) The Sun The Sun & Solar Physics Uncategorized Venus Volcanoes Wind Mission Explore More
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