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The powerful vision of NASA's Hubble Space Telescope has allowed astronomers to study for the first time the layer-cake structure of the atmosphere of a planet orbiting another star. Hubble discovered a dense upper layer of hot hydrogen gas where the super-hot planet's atmosphere is bleeding off into space.

This is an artist's illustration of the extrasolar planet, designated HD 209458b, which is unlike any world in our solar system. It completes an orbit around its host star every 3.5 days. It is about the size of Jupiter. Unlike Jupiter, HD 290458b is so hot that its atmosphere is "puffed up." Starlight is heating the planet's atmosphere, causing hot gas to escape into space. Astronomers used Hubble to analyze the starlight that filtered through the planet's atmosphere. Imprinted on the starlight is information about the atmosphere's structure and chemical makeup.

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    • By NASA
      9 Min Read Towards Autonomous Surface Missions on Ocean Worlds
      Artist’s concept image of a spacecraft lander with a robot arm on the surface of Europa. Credits:
      NASA/JPL – Caltech Through advanced autonomy testbed programs, NASA is setting the groundwork for one of its top priorities—the search for signs of life and potentially habitable bodies in our solar system and beyond. The prime destinations for such exploration are bodies containing liquid water, such as Jupiter’s moon Europa and Saturn’s moon Enceladus. Initial missions to the surfaces of these “ocean worlds” will be robotic and require a high degree of onboard autonomy due to long Earth-communication lags and blackouts, harsh surface environments, and limited battery life.
      Technologies that can enable spacecraft autonomy generally fall under the umbrella of Artificial Intelligence (AI) and have been evolving rapidly in recent years. Many such technologies, including machine learning, causal reasoning, and generative AI, are being advanced at non-NASA institutions.  
      NASA started a program in 2018 to take advantage of these advancements to enable future icy world missions. It sponsored the development of the physical Ocean Worlds Lander Autonomy Testbed (OWLAT) at NASA’s Jet Propulsion Laboratory in Southern California and the virtual Ocean Worlds Autonomy Testbed for Exploration, Research, and Simulation (OceanWATERS) at NASA’s Ames Research Center in Silicon Valley, California.
      NASA solicited applications for its Autonomous Robotics Research for Ocean Worlds (ARROW) program in 2020, and for the Concepts for Ocean worlds Life Detection Technology (COLDTech) program in 2021. Six research teams, based at universities and companies throughout the United States, were chosen to develop and demonstrate autonomy solutions on OWLAT and OceanWATERS. These two- to three-year projects are now complete and have addressed a wide variety of autonomy challenges faced by potential ocean world surface missions.
      OWLAT
      OWLAT is designed to simulate a spacecraft lander with a robotic arm for science operations on an ocean world body. The overall OWLAT architecture including hardware and software components is shown in Figure 1. Each of the OWLAT components is detailed below.
      Figure 1. The software and hardware components of the Ocean Worlds Lander Autonomy Testbed and the relationships between them. NASA/JPL – Caltech The hardware version of OWLAT (shown in Figure 2) is designed to physically simulate motions of a lander as operations are performed in a low-gravity environment using a six degrees-of-freedom (DOF) Stewart platform. A seven DOF robot arm is mounted on the lander to perform sampling and other science operations that interact with the environment. A camera mounted on a pan-and-tilt unit is used for perception. The testbed also has a suite of onboard force/torque sensors to measure motion and reaction forces as the lander interacts with the environment. Control algorithms implemented on the testbed enable it to exhibit dynamics behavior as if it were a lightweight arm on a lander operating in different gravitational environments.
      Figure 2. The Ocean Worlds Lander Autonomy Testbed. A scoop is mounted to the end of the testbed robot arm. NASA/JPL – Caltech The team also developed a set of tools and instruments (shown in Figure 3) to enable the performance of science operations using the testbed. These various tools can be mounted to the end of the robot arm via a quick-connect-disconnect mechanism. The testbed workspace where sampling and other science operations are conducted incorporates an environment designed to represent the scene and surface simulant material potentially found on ocean worlds.
      Figure 3. Tools and instruments designed to be used with the testbed. NASA/JPL – Caltech The software-only version of OWLAT models, visualizes, and provides telemetry from a high-fidelity dynamics simulator based on the Dynamics And Real-Time Simulation (DARTS) physics engine developed at JPL. It replicates the behavior of the physical testbed in response to commands and provides telemetry to the autonomy software. A visualization from the simulator is shown on Figure 4.
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      supports HTML5 video
      Figure 7. Screenshot of OceanWATERS lander on a terrain modeled from the Atacama Desert. A scoop operation has just been completed. NASA/JPL – Caltech The autonomy software module shown at the top in Figure 1 interacts with the testbed through a Robot Operating System (ROS)-based interface to issue commands and receive telemetry. This interface is defined to be identical to the OceanWATERS interface. Commands received from the autonomy module are processed through the dispatcher/scheduler/controller module (blue box in Figure 1) and used to command either the physical hardware version of the testbed or the dynamics simulation (software version) of the testbed. Sensor information from the operation of either the software-only or physical testbed is reported back to the autonomy module using a defined telemetry interface. A safety and performance monitoring and evaluation software module (red box in Figure 1) ensures that the testbed is kept within its operating bounds. Any commands causing out of bounds behavior and anomalies are reported as faults to the autonomy software module.
      Figure 5. Erica Tevere (at the operator’s station) and Ashish Goel (at the robot arm) setting up the OWLAT testbed for use. NASA/JPL – Caltech OceanWATERS
      At the time of the OceanWATERS project’s inception, Jupiter’s moon Europa was planetary science’s first choice in searching for life. Based on ROS, OceanWATERS is a software tool that provides a visual and physical simulation of a robotic lander on the surface of Europa (see Figure 6). OceanWATERS realistically simulates Europa’s celestial sphere and sunlight, both direct and indirect. Because we don’t yet have detailed information about the surface of Europa, users can select from terrain models with a variety of surface and material properties. One of these models is a digital replication of a portion of the Atacama Desert in Chile, an area considered a potential Earth-analog for some extraterrestrial surfaces.
      Figure 6. Screenshot of OceanWATERS. NASA/JPL – Caltech JPL’s Europa Lander Study of 2016, a guiding document for the development of OceanWATERS, describes a planetary lander whose purpose is collecting subsurface regolith/ice samples, analyzing them with onboard science instruments, and transmitting results of the analysis to Earth.
      The simulated lander in OceanWATERS has an antenna mast that pans and tilts; attached to it are stereo cameras and spotlights. It has a 6 degree-of-freedom arm with two interchangeable end effectors—a grinder designed for digging trenches, and a scoop for collecting ground material. The lander is powered by a simulated non-rechargeable battery pack. Power consumption, the battery’s state, and its remaining life are regularly predicted with the Generic Software Architecture for Prognostics (GSAP) tool. To simulate degraded or broken subsystems, a variety of faults (e.g., a frozen arm joint or overheating battery) can be “injected” into the simulation by the user; some faults can also occur “naturally” as the simulation progresses, e.g., if components become over-stressed. All the operations and telemetry (data measurements) of the lander are accessible via an interface that external autonomy software modules can use to command the lander and understand its state. (OceanWATERS and OWLAT share a unified autonomy interface based on ROS.) The OceanWATERS package includes one basic autonomy module, a facility for executing plans (autonomy specifications) written in the PLan EXecution Interchange Language, or PLEXIL. PLEXIL and GSAP are both open-source software packages developed at Ames and available on GitHub, as is OceanWATERS.
      Mission operations that can be simulated by OceanWATERS include visually surveying the landing site, poking at the ground to determine its hardness, digging a trench, and scooping ground material that can be discarded or deposited in a sample collection bin. Communication with Earth, sample analysis, and other operations of a real lander mission, are not presently modeled in OceanWATERS except for their estimated power consumption. Figure 7 is a video of OceanWATERS running a sample mission scenario using the Atacama-based terrain model.
      To view this video please enable JavaScript, and consider upgrading to a web browser that
      supports HTML5 video
      Figure 7. Screenshot of OceanWATERS lander on a terrain modeled from the Atacama Desert. A scoop operation has just been completed. NASA/JPL – Caltech Because of Earth’s distance from the ocean worlds and the resulting communication lag, a planetary lander should be programmed with at least enough information to begin its mission. But there will be situation-specific challenges that will require onboard intelligence, such as deciding exactly where and how to collect samples, dealing with unexpected issues and hardware faults, and prioritizing operations based on remaining power. 
      Results
      All six of the research teams funded by the ARROW and COLDTech programs used OceanWATERS to develop ocean world lander autonomy technology and three of those teams also used OWLAT. The products of these efforts were published in technical papers, and resulted in development of software that may be used or adapted for actual ocean world lander missions in the future. The following table summarizes the ARROW and COLDTech efforts.
        Principal Investigator (PI) PI Institution Project Testbed Used Purpose of Project ARROW Projects Jonathan Bohren Honeybee Robotics Stochastic PLEXIL (SPLEXIL) OceanWATERS Extended PLEXIL with stochastic decision-making capabilities by employing reinforcement learning techniques. Pooyan Jamshidi University of South Carolina Resource Adaptive Software Purpose-Built for Extraordinary Robotic Research Yields (RASPBERRY SI) OceanWATERS & OWLAT Developed software algorithms and tools for fault root cause identification, causal debugging, causal optimization, and causal-induced verification. COLDTech Projects Eric Dixon Lockheed Martin Causal And Reinforcement Learning (CARL) for COLDTech OceanWATERS Integrated a model of JPL’s mission-ready Cold Operable Lunar Deployable Arm (COLDarm) into OceanWATERS and applied image analysis, causal reasoning, and machine learning models to identify and mitigate the root causes of faults, such as ice buildup on the arm’s end effector. Jay McMahon University of Colorado Robust Exploration with Autonomous Science On-board, Ranked Evaluation of Contingent Opportunities for Uninterrupted Remote Science Exploration (REASON-RECOURSE) OceanWATERS Applied automated planning with formal methods to maximize science return of the lander while minimizing communication with ground team on Earth. Melkior Ornik U Illinois, Urbana-Champaign aDaptive, ResIlient Learning-enabLed oceAn World AutonomY (DRILLAWAY) OceanWATERS & OWLAT Developed autonomous adaptation to novel terrains and selecting scooping actions based on the available image data and limited experience by transferring the scooping procedure learned from a low-fidelity testbed to the high-fidelity OWLAT testbed. Joel Burdick Caltech Robust, Explainable Autonomy for Scientific Icy Moon Operations (REASIMO) OceanWATERS & OWLAT Developed autonomous 1) detection and identification of off-nominal conditions and procedures for recovery from those conditions, and 2) sample site selection Acknowledgements: The portion of the research carried out at the Jet Propulsion Laboratory, California Institute of Technology was performed under a contract with the National Aeronautics and Space Administration (80NM0018D0004).  The portion of the research carried out by employees of KBR Wyle Services LLC at NASA Ames Research Center was performed under a contract with the National Aeronautics and Space Administration (80ARC020D0010). Both were funded by the Planetary Science Division ARROW and COLDTech programs.
      Project Leads: Hari Nayar (NASA Jet Propulsion Laboratory, California Institute of Technology), K. Michael Dalal (KBR, Inc. at NASA Ames Research Center)
      Sponsoring Organizations: NASA SMD PESTO
      View the full article
    • By NASA
      Hubble Space Telescope Home Hubble Captures an Edge-On… 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   2 min read
      Hubble Captures an Edge-On Spiral with Curve Appeal
      This NASA/ESA Hubble Space Telescope image features spiral galaxy UGC 10043. ESA/Hubble & NASA, R. Windhorst, W. Keel
      Download this image

      This NASA/ESA Hubble Space Telescope image features a spiral galaxy, named UGC 10043. We don’t see the galaxy’s spiral arms because we are seeing it from the side. Located roughly 150 million light-years from Earth in the constellation Serpens, UGC 10043 is one of the somewhat rare spiral galaxies that we see edge-on.
      This edge-on viewpoint makes the galaxy’s disk appear as a sharp line through space, with its prominent dust lanes forming thick bands of clouds that obscure our view of the galaxy’s glow. If we could fly above the galaxy, viewing it from the top down, we would see this dust scattered across UGC 10043, possibly outlining its spiral arms. Despite the dust’s obscuring nature, some active star-forming regions shine out from behind the dark clouds. We can also see that the galaxy’s center sports a glowing, almost egg-shaped ‘bulge’, rising far above and below the disk. All spiral galaxies have a bulge similar to this one as part of their structure. These bulges hold stars that orbit the galactic center on paths above and below the whirling disk; it’s a feature that isn’t normally obvious in pictures of galaxies. The unusually large size of this bulge compared to the galaxy’s disk is possibly due to UGC 10043 siphoning material from a nearby dwarf galaxy. This may also be why its disk appears warped, bending up at one end and down at the other.
      Like most full-color Hubble images, this image is a composite, made up of several individual snapshots taken by Hubble at different times, each capturing different wavelengths of light. One notable aspect of this image is that the two sets of data that comprise this image were collected 23 years apart, in 2000 and 2023! Hubble’s longevity doesn’t just afford us the ability to produce new and better images of old targets; it also provides a long-term archive of data which only becomes more and more useful to astronomers.
      Facebook logo @NASAHubble @NASAHubble Instagram logo @NASAHubble Media Contact:
      Claire Andreoli
      NASA’s Goddard Space Flight Center, Greenbelt, MD
      claire.andreoli@nasa.gov
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      Details
      Last Updated Nov 21, 2024 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Related Terms
      Astrophysics Astrophysics Division Galaxies Goddard Space Flight Center Hubble Space Telescope Spiral Galaxies Keep Exploring Discover More Topics From Hubble
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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
      Download this image

      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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    • By NASA
      To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video
      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.
      To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video
      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.
      View the full article
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