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Astronomers Ponder Lack of Planets in Globular Cluster
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By NASA
4 min read
December’s Night Sky Notes: Spot the King of Planets
by Kat Troche of the Astronomical Society of the Pacific
Jupiter is our solar system’s undisputed king of the planets! Jupiter is bright and easy to spot from our vantage point on Earth, helped by its massive size and banded, reflective cloud tops. Jupiter even possesses moons the size of planets: Ganymede, its largest, is bigger than the planet Mercury. What’s more, you can easily observe Jupiter and its moons with a modest instrument, just like Galileo did over 400 years ago.
This image taken on Feb. 7 by NASA’s Juno spacecraft, reveals swirling cloud formations in the northern area of Jupiter’s north temperate belt. Citizen scientist Kevin M. Gill processed the image using data from the JunoCam imager. NASA, JPL-Caltech, SwRI, MSSS | Image processing by Kevin M. Gill, © CC BY Jupiter’s position as our solar system’s largest planet is truly earned; you could fit 11 Earths along Jupiter’s diameter, and in case you were looking to fill up Jupiter with some Earth-size marbles, you would need over 1300 Earths to fill it up – and that would still not be quite enough! However, despite its formidable size, Jupiter’s true rule over the outer solar system comes from its enormous mass. If you took all of the planets in our solar system and put them together, they would still only be half as massive as Jupiter all by itself. Jupiter’s mighty mass has shaped the orbits of countless comets and asteroids. Its gravity can fling these tiny objects towards our inner solar system and also draw them into itself, as famously observed in 1994 when Comet Shoemaker-Levy 9, drawn towards Jupiter in previous orbits, smashed into the gas giant’s atmosphere. Its multiple fragments slammed into Jupiter’s cloud tops with such violence that the fireballs and dark impact spots were not only seen by NASA’s orbiting Galileo probe but also by observers back on Earth!
Look for Jupiter near the Eye of the Bull, Aldebaran, in the Taurus constellation on the evening of December 15, 2024. Binoculars may help you spot Jupiter’s moons as small bright star-like objects on either side of the planet. A small telescope will show them easily, along with Jupiter’s famed cloud bands. How many can you count? Credit: Stellarium Web Jupiter is easy to observe at night with our unaided eyes, as well-documented by the ancient astronomers who carefully recorded its slow movements from night to night. It can be one of the brightest objects in our nighttime skies, bested only by the Moon, Venus, and occasionally Mars, when the red planet is at opposition. That’s impressive for a planet that, at its closest to Earth, is still over 365 million miles (587 million km) away. It’s even more impressive that the giant world remains very bright to Earthbound observers at its furthest distance: 600 million miles (968 million km)! While the King of Planets has a coterie of 95 known moons, only the four large moons that Galileo originally observed in 1610 – Io, Europa, Ganymede, and Calisto – can be easily observed by Earth-based observers with very modest equipment. These are called, appropriately enough, the Galilean moons. Most telescopes will show the moons as faint star-like objects neatly lined up close to bright Jupiter. Most binoculars will show at least one or two moons orbiting the planet. Small telescopes will show all four of the Galilean moons if they are all visible, but sometimes they can pass behind or in front of Jupiter or even each other. Telescopes will also show details like Jupiter’s cloud bands and, if powerful enough, large storms like its famous Great Red Spot, and the shadows of the Galilean moons passing between the Sun and Jupiter. Sketching the positions of Jupiter’s moons during the course of an evening – and night to night – can be a rewarding project! You can download an activity guide from the Astronomical Society of the Pacific at bit.ly/drawjupitermoons
Now in its eighth year, NASA’s Juno mission is one of just nine spacecraft to have visited this impressive world. Juno entered Jupiter’s orbit in 2016 to begin its initial mission to study this giant world’s mysterious interior. The years have proven Juno’s mission a success, with data from the probe revolutionizing our understanding of this gassy world’s guts. Juno’s mission has since been extended to include the study of its large moons, and since 2021 the plucky probe, increasingly battered by Jupiter’s powerful radiation belts, has made close flybys of the icy moons Ganymede and Europa, along with volcanic Io. What else will we potentially learn in 2030 with the Europa Clipper mission?
Find the latest discoveries from Juno and NASA’s missions to Jupiter at science.nasa.gov/jupiter/
Originally posted by Dave Prosper: February 2023
Last Updated by Kat Troche: November 2024
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By NASA
This illustration shows a red, early-universe dwarf galaxy that hosts a rapidly feeding black hole at its center. Using data from NASA’s James Webb Space Telescope and Chandra X-ray Observatory, a team of astronomers have discovered this low-mass supermassive black hole at the center of a galaxy just 1.5 billion years after the Big Bang. It is pulling in matter at a phenomenal rate — over 40 times the theoretical limit. While short lived, this black hole’s “feast” could help astronomers explain how supermassive black holes grew so quickly in the early universe.NOIRLab/NSF/AURA/J. da Silva/M. Zamani A rapidly feeding black hole at the center of a dwarf galaxy in the early universe, shown in this artist’s concept, may hold important clues to the evolution of supermassive black holes in general.
Using data from NASA’s James Webb Space Telescope and Chandra X-ray Observatory, a team of astronomers discovered this low-mass supermassive black hole just 1.5 billion years after the big bang. The black hole is pulling in matter at a phenomenal rate — over 40 times the theoretical limit. While short lived, this black hole’s “feast” could help astronomers explain how supermassive black holes grew so quickly in the early universe.
Supermassive black holes exist at the center of most galaxies, and modern telescopes continue to observe them at surprisingly early times in the universe’s evolution. It’s difficult to understand how these black holes were able to grow so big so rapidly. But with the discovery of a low-mass supermassive black hole feasting on material at an extreme rate so soon after the birth of the universe, astronomers now have valuable new insights into the mechanisms of rapidly growing black holes in the early universe.
The black hole, called LID-568, was hidden among thousands of objects in the Chandra X-ray Observatory’s COSMOS legacy survey, a catalog resulting from some 4.6 million Chandra observations. This population of galaxies is very bright in the X-ray light, but invisible in optical and previous near-infrared observations. By following up with Webb, astronomers could use the observatory’s unique infrared sensitivity to detect these faint counterpart emissions, which led to the discovery of the black hole.
The speed and size of these outflows led the team to infer that a substantial fraction of the mass growth of LID-568 may have occurred in a single episode of rapid accretion.
LID-568 appears to be feeding on matter at a rate 40 times its Eddington limit. This limit relates to the maximum amount of light that material surrounding a black hole can emit, as well as how fast it can absorb matter, such that its inward gravitational force and outward pressure generated from the heat of the compressed, infalling matter remain in balance.
These results provide new insights into the formation of supermassive black holes from smaller black hole “seeds,” which current theories suggest arise either from the death of the universe’s first stars (light seeds) or the direct collapse of gas clouds (heavy seeds). Until now, these theories lacked observational confirmation.
The new discovery suggests that “a significant portion of mass growth can occur during a single episode of rapid feeding, regardless of whether the black hole originated from a light or heavy seed,” said International Gemini Observatory/NSF NOIRLab astronomer Hyewon Suh, who led the research team.
A paper describing these results (“A super-Eddington-accreting black hole ~1.5 Gyr after the Big Bang observed with JWST”) appears in the journal Nature Astronomy.
About the Missions
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.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
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
News Media Contact
Elizabeth Laundau
NASA Headquarters
Washington, DC
202-923-0167
elizabeth.r.landau@nasa.gov
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/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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