Could This Supermassive Black Hole Only Have Formed by Direct Collapse?

Artist's impression of an active supermassive black hole in the early universe. Credit: NOIRLab/NSF/AURA/J. da Silva

Nearly every galaxy in the universe contains a supermassive black hole. Even galaxies that are billions of light years away. This means supermassive black holes form early in the development of a galaxy. They are possibly even the gravitational seeds around which a galaxy forms. But astronomers are still unclear about just how these massive gravitational beasts first appeared.

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What Would the Milky Way Look Like From Afar?

A view of the Milky Way from Paranal, Chile. Credit: ESO/Y. Beletsky

Our understanding of galaxies is rooted in the fact that we can see so many of them. Some, such as the Andromeda and Pinwheel galaxies are fairly close, and others are more distant, but all of them give a unique view. Because of this, we can see how the various types of galaxies appear from different points of view, from face-on to edge-on and all angles in between. But there is one galaxy that’s a bit harder to map out, and that’s our own. Because we are in the galactic plane of the Milky Way, it can be difficult to create an accurate bird’s-eye view of our home galaxy. That’s where a recent study in Nature Astronomy comes in.

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New Clues to the Formation of Globular Clusters: Their Ultramassive Stars

The scattered stars of the globular cluster NGC 6355 are strewn across this image from the NASA/ESA Hubble Space Telescope. This globular cluster lies less than 50,000 light-years from Earth in the Ophiuchus constellation. Image Credit: ESA/Hubble & NASA, E. Noyola, R. Cohen

Globular clusters are odd beasts. They aren’t galaxies, but like galaxies, they are a gravitationally bound collection of stars. They can contain millions of stars densely packed together, and they are old. Really old. They likely formed when the universe was only about 400 million years old. But the details of their origins are still unclear.

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JWST Fails to Disprove the Big Bang

A portion of the Renaissance Simulation centered on a cluster of young galaxies. Credit: Advanced Visualization Lab, National Center for Supercomputing Applications

The James Webb Space Telescope (JWST) is revolutionizing our understanding of the early universe. With a mirror larger than Hubble and the ability to observe deep into the infrared, JWST is giving us a detailed view of that period of the universe when galaxies were just starting to form. The results have been surprising, leading some to argue that they disprove the big bang. But the big bang is still intact, as a recent study shows.

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A Star was Blocking a Galaxy, but Now it’s Moved Enough That Astronomers can Finally Examine What it Was Hiding

NASA's Hubble Space Telescope captured a detailed image of the tiny galaxy HIPASS J1131–31, nicknamed the "Peekaboo Galaxy." It's more like an ancient galaxy from the Universe's early days than a modern galaxy. Image Credit: NASA, ESA, and Igor Karachentsev (SAO RAS); Image Processing: Alyssa Pagan (STScI)

One of the biggest puzzles in astronomy, and one of the hardest ones to solve, concerns the formation and evolution of galaxies. What did the first ones look like? How have they grown so massive?

A tiny galaxy only 20 million light-years away might be a piece of the puzzle.

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How Do Stars Get Kicked Out of Globular Clusters?

Hubble image of Messier 54, a globular cluster located in the Sagittarius Dwarf Galaxy. Credit: ESA/Hubble & NASA

Globular clusters are densely-packed collections of stars bound together gravitationally in roughly-shaped spheres. They contain hundreds of thousands of stars. Some might contain millions of stars.

Sometimes globular clusters (GCs) kick stars out of their gravitational group. How does that work?

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The Dark Energy Camera has Captured a Million Images, an Eighth of the Entire sky. Here are Some of its Best Pictures so far

Ten areas in the sky were selected as “deep fields” that the Dark Energy Camera imaged several times during the survey, providing a glimpse of distant galaxies and helping determine their 3D distribution in the cosmos. Credit: NSF/DES/NOIRLab/DOE/FNAL/AURA/University of Alaska Anchorage/

In August 2013, the Dark Energy Survey (DES) began its six-year mission to map thousands of galaxies, supernovae, and patterns in the cosmic structure. This international collaborative effort is dedicated to investigating the mysterious phenomenon known as Dark Energy. This theoretical force counter-acts gravity and accounts for 70% of the Universe’s energy-mass density. Their primary instrument in this mission is the 570-megapixel Dark Energy Camera (DECam), mounted on the Victor M. Blanco 5-meter (16.4 ft) telescope at the Cerro Tlelolo Inter-American Observatory in Chile.

Between 2013 and 2019, the DECam took over one million exposures of the southern night sky and photographed around 2.5 billion astronomical objects – including galaxies, galaxy clusters, stars, comets, asteroids, dwarf planets, and supernovae. For our viewing pleasure, the Dark Energy Survey recently released fifteen spectacular images taken by the DECam during the six-year campaign. These images showcase the capabilities of the DECam, the types of objects it observed, and the sheer beauty of the Universe!

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Primordial Black Holes Could Have Triggered the Formation of Supermassive Black Holes

Artist view of merging black holes in the early universe. Credit: LIGO/Caltech/MIT/R. Hurt (IPAC)

The early moments of the universe were turbulent and filled with hot and dense matter. Fluctuations in the early universe could have been great enough that stellar-mass pockets of matter collapsed under their own weight to create primordial black holes. Although we’ve never detected these small black holes, they could have played a vital role in cosmic evolution, perhaps growing into the supermassive black holes we see today. A new study shows how this could work, but also finds the process is complicated.

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Supermassive Black Holes Shut Down Star Formation

The Cigar Galaxy (M82), which is a starburst galaxy with high star production. Credit: NASA, ESA and the Hubble Heritage Team (STScI/AURA)

One of the key aspects of galactic evolution is star production. On a basic level, stars form within a galaxy’s gas and dust all the time, and where they form can help determine a galaxy’s shape and size. But there seems to be a sweet point when star production in a galaxy is particularly strong. Galaxies often have a period of rapid star production which then drops off. Astronomers are still trying to understand what causes this drop-off.

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The Milky Way’s Most Recent Meal was a Galaxy it Gobbled up 8-10 Billion Years ago

Gaia-Enceladus in a simulation of a galactic merger with the Milky Way matching Gaia data. Credit: ESA (artist’s impression and composition); Koppelman, Villalobos and Helmi (simulation)

A central aspect of galactic evolution is that they must eat or be eaten. Dark energy strives to push galaxies apart, but gravity tries to pull them together. As a result, galaxies tend to form into local groups. As these superclusters of galaxies become more isolated due to cosmic expansion, they gravitationally turn on each other, and in time the largest galaxies of the group will consume the smaller ones. The Milky Way is one of the larger galaxies in our local group, and so it has consumed smaller galaxies in the past. But piecing together the history of these galactic meals is a real challenge.

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