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By European Space Agency
A mesmerising audiovisual experience from trip-hop collective Massive Attack that blends an original score with stunning satellite images of Earth was enjoyed by thousands of climate enthusiasts in Liverpool.
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By NASA
X-ray: NASA/CXC/SAO/J. Drake et al, IR: NASA/JPL-Caltech/Spitzer; Image Processing: NASA/CXC/SAO/N. Wolk Most stars form in collections, called clusters or associations, that include very massive stars. These giant stars send out large amounts of high-energy radiation, which can disrupt relatively fragile disks of dust and gas that are in the process of coalescing to form new planets.
A team of astronomers used NASA’s Chandra X-ray Observatory, in combination with ultraviolet, optical, and infrared data, to show where some of the most treacherous places in a star cluster may be, where planets’ chances to form are diminished.
The target of the observations was Cygnus OB2, which is the nearest large cluster of stars to our Sun — at a distance of about 4,600 light-years. The cluster contains hundreds of massive stars as well as thousands of lower-mass stars. The team used long Chandra observations pointing at different regions of Cygnus OB2, and the resulting set of images were then stitched together into one large image.
The deep Chandra observations mapped out the diffuse X-ray glow in between the stars, and they also provided an inventory of the young stars in the cluster. This inventory was combined with others using optical and infrared data to create the best census of young stars in the cluster.
In this new composite image, the Chandra data (purple) shows the diffuse X-ray emission and young stars in Cygnus OB2, and infrared data from NASA’s now-retired Spitzer Space Telescope (red, green, blue, and cyan) reveals young stars and the cooler dust and gas throughout the region.
In these crowded stellar environments, copious amounts of high-energy radiation produced by stars and planets are present. Together, X-rays and intense ultraviolet light can have a devastating impact on planetary disks and systems in the process of forming.
Planet-forming disks around stars naturally fade away over time. Some of the disk falls onto the star and some is heated up by X-ray and ultraviolet radiation from the star and evaporates in a wind. The latter process, known as “photoevaporation,” usually takes between 5 and 10 million years with average-sized stars before the disk disappears. If massive stars, which produce the most X-ray and ultraviolet radiation, are nearby, this process can be accelerated.
The researchers using this data found clear evidence that planet-forming disks around stars indeed disappear much faster when they are close to massive stars producing a lot of high-energy radiation. The disks also disappear more quickly in regions where the stars are more closely packed together.
For regions of Cygnus OB2 with less high-energy radiation and lower numbers of stars, the fraction of young stars with disks is about 40%. For regions with more high-energy radiation and higher numbers of stars, the fraction is about 18%. The strongest effect — meaning the worst place to be for a would-be planetary system — is within about 1.6 light-years of the most massive stars in the cluster.
A separate study by the same team examined the properties of the diffuse X-ray emission in the cluster. They found that the higher-energy diffuse emission comes from areas where winds of gas blowing away from massive stars have collided with each other. This causes the gas to become hotter and produce X-rays. The less energetic emission probably comes from gas in the cluster colliding with gas surrounding the cluster.
Two separate papers describing the Chandra data of Cygnus OB2 are available. The paper about the planetary danger zones, led by Mario Giuseppe Guarcello (National Institute for Astrophysics in Palermo, Italy), appeared in the November 2023 issue of the Astrophysical Journal Supplement Series, and is available here. The paper about the diffuse emission, led by Juan Facundo Albacete-Colombo (University of Rio Negro in Argentina) was published in the same issue of Astrophysical Journal Supplement, and is available here.
NASA’s Marshall Space Flight Center in Huntsville, Alabama, 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.
JPL managed the Spitzer Space Telescope mission for NASA’s Science Mission Directorate in Washington until the mission was retired in January 2020. Science operations were conducted at the Spitzer Science Center at Caltech. Spacecraft operations were based at Lockheed Martin Space in Littleton, Colorado. Data are archived at the Infrared Science Archive operated by IPAC at Caltech. Caltech manages JPL for NASA.
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 a composite image of the Cygnus OB2 star cluster, which resembles a night sky blanketed in orange, purple, and grey clouds.
The center of the square image is dominated by purple haze. This haze represents diffuse X-ray emissions, and young stars, detected by the Chandra X-ray observatory. Surrounding the purple haze is a mottled, streaky, brick orange cloud. Another cloud resembling a tendril of grey smoke stretches from our lower left to the center of the image. These clouds represent relatively cool dust and gas observed by the Spitzer Space Telescope.
Although the interwoven clouds cover most of the image, the thousands of stars within the cluster shine through. The lower-mass stars present as tiny specks of light. The massive stars gleam, some with long refraction spikes.
News Media Contact
Megan Watzke
Chandra X-ray Center
Cambridge, Mass.
617-496-7998
mwatzke@cfa.harvard.edu
Lane Figueroa
Marshall Space Flight Center, Huntsville, Alabama
256-544-0034
lane.e.figueroa@nasa.gov
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By NASA
X-ray: NASA/CXC/Xiamen Univ./C. Ge; Optical: DESI collaboration; Image Processing: NASA/CXC/SAO/N. Wolk Astronomers using NASA’s Chandra X-ray Observatory have found a galaxy cluster has two streams of superheated gas crossing one another. This result shows that crossing the streams may lead to the creation of new structure.
Researchers have discovered an enormous, comet-like tail of hot gas — spanning over 1.6 million light-years long — trailing behind a galaxy within the galaxy cluster called Zwicky 8338 (Z8338 for short). This tail, spawned as the galaxy had some of its gas stripped off by the hot gas it is hurtling through, has split into two streams.
This is the second pair of tails trailing behind a galaxy in this system. Previously, astronomers discovered a shorter pair of tails from a different galaxy near this latest one. This newer and longer set of tails was only seen because of a deeper observation with Chandra that revealed the fainter X-rays.
Researchers have discovered a second pair of tails trailing behind a galaxy in this cluster. Previously, astronomers discovered a shorter pair of tails from a different galaxy close to this latest one. This newer and longer set of tails was only seen because of a deeper observation with Chandra that revealed the fainter X-rays that have been shown in the optical data. These tails span for over a million light-years and help determine the evolution of the galaxy cluster.X-ray: NASA/CXC/Xiamen Univ./C. Ge; Optical: DESI collaboration; Image Processing: NASA/CXC/SAO/N. Wolk Astronomers now have evidence that these streams trailing behind the speeding galaxies have crossed one another. Z8338 is a chaotic landscape of galaxies, superheated gas, and shock waves (akin to sonic booms created by supersonic jets) in one relatively small region of space. These galaxies are in motion because they were part of two galaxy clusters that collided with each other to create Z8338.
This new composite image shows this spectacle. X-rays from Chandra (represented in purple) outline the multimillion-degree gas that outweighs all of the galaxies in the cluster. The Chandra data also shows where this gas has been jettisoned behind the moving galaxies. Meanwhile an optical image from the Dark Energy Survey from the Cerro Tololo Inter-American Observatory in Chile shows the individual galaxies peppered throughout the same field of view.
The original gas tail discovered in Z8338 is about 800,000 light-years long and is seen as vertical in this image (see the labeled version). The researchers think the gas in this tail is being stripped away from a large galaxy as it travels through the galaxy cluster. The head of the tail is a cloud of relatively cool gas about 100,000 light-years away from the galaxy it was stripped from. This tail is also separated into two parts.
The team proposes that the detachment of the tail from the large galaxy may have been caused by the passage of the other, longer tail. Under this scenario, the tail detached from the galaxy because of the crossing of the streams.
The results give useful information about the detachment and destruction of clouds of cooler gas like those seen in the head of the detached tail. This work shows that the cloud can survive for at least 30 million years after it is detached. During that time, a new generation of stars and planets may form within it.
The Z8338 galaxy cluster and its jumble of galactic streams are located about 670 million light-years from Earth. A paper describing these results appeared in the Aug. 8, 2023, issue of the Monthly Notices of the Royal Astronomical Society and is available online at: https://academic.oup.com/mnras/article/525/1/1365/7239302.
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 a composite image of two pairs of hot gas tails found inside a single galaxy cluster. The image is presented both labeled and unlabeled, with color-coded ovals encircling the hot gas tails.
In both the labeled and unlabeled versions of the image, mottled purple gas speckles a region of space dotted with distant flecks of red and white. Also present in this region of space are several glowing golden dots. These dots are individual galaxies that together form the cluster Zwicky 8338.
To our right of center is a glowing golden galaxy with a mottled V shaped cloud of purple above it. Yellow labels identify the two arms of the V as tails trailing behind the hurtling galaxy below.
To our left of center is another golden galaxy, this one surrounded by purple gas. Behind it, opening toward our right in the shape of a widening V lying on its side, are two more mottled purple clouds. Labeled in white, these newly-discovered gas tails are even larger than the previously discovered tails labeled in yellow. These tails, which overlap with the galaxy on our right, are over 1.6 million light-years long.
News Media Contact
Megan Watzke
Chandra X-ray Center
Cambridge, Mass.
617-496-7998
Lane Figueroa
Marshall Space Flight Center, Huntsville, Alabama
256-544-0034
lane.e.figueroa@nasa.gov
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By European Space Agency
The first satellite in ESA’s Cluster quartet safely came back down to Earth last night in a world-first ‘targeted reentry’, marking a brilliant end to this remarkable mission.
The spacecraft, dubbed ‘Salsa’ (Cluster 2), reentered Earth’s atmosphere at 20:47 CEST on 8 September 2024 over the South Pacific Ocean. In this region, any risk of fragments reaching land are absolutely minimised.
During the last two decades Cluster has spent in space, it has provided invaluable data on how the Sun interacts with Earth’s magnetic field, helping us better understand and forecast space weather. With this first-ever targeted reentry, Cluster will go down in history for a second reason – helping ESA become a world-leader in sustainable space exploration.
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By European Space Agency
Video: 00:06:50 The first of four satellites that make up ESA’s Cluster mission is coming safely back down to Earth, marking a brilliant end to this remarkable mission.
The satellite’s orbit was tweaked back in January to target a region as far as possible from populated regions. This ensures that any spacecraft parts that survive the reentry will fall over open ocean.
During 24 years in space, Cluster has sent back precious data on how the Sun interacts with Earth’s magnetic field, helping us better understand and forecast potentially dangerous space weather.
With this first ever targeted reentry, Cluster goes down in history for a different reason, taking ESA well beyond international space safety standards and helping ensure the long-term sustainability of space activities.
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