JWST tagged posts

ASTRID traces 13.5 billion years of black hole and galaxy evolution

In dark skies at night, distant starlight twinkles and speaks to vast cosmic histories almost as old as time itself. New data from instruments such as NASA’s James Webb Space Telescope are helping astrophysicists probe deep cosmic mysteries, including the evolution of black holes and galaxies.

Using supercomputers to help make sense of the data, researchers from multiple institutions worked together to complete the largest cosmological hydrodynamic simulation, called ASTRID—a mind-boggling computational run that traces the evolution of the universe from its earliest times to the present.

“The most important information about our recent study is that we’ve evolved the ASTRID simulation to z = 0, and that these data are available,” said Yihao Zhou, a Ph.D...

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JWST spots a bizarre “black hole star” 100 billion times brighter than a star

Three images show a “Star” as a cut-away sphere with a yellow core; a “Black Hole Accretion Disk” with black core and blue pancake spiral; and the “Black Hole Star,” an amorphous red cloud with a black center.
Stars (left) can be thought of as a dense ball of gas powered by nuclear fusion at their centers. Black holes (center) typically grow by consuming matter via a pancake-like accretion disk. Black hole stars (right) represent a new kind of object — nascent black holes enshrouded in dense gas such that they effectively radiate in a star-like manner. The accreting black hole, as the power source, plays the role of nuclear fusion, and the dense surrounding gas acts similarly to a pseudo-photosphere.
Image: iStock; Jose-Luis Olivares, MIT

Astronomers may have uncovered an entirely new cosmic object: a gigantic “black hole star” that could explain the mysterious red dots filling the early universe...

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Webb reveals oxygen-rich dust and water surviving near Milky Way’s central black hole

IRS 3 Field (NIRCam and MIRI image)

Using the NASA/ESA/CSA James Webb Space Telescope, an international team of astronomers has discovered that dust and water can form and survive surprisingly close to the supermassive black hole at the center of the Milky Way galaxy. The observations reveal that the evolved star IRS3 continues to enrich its surroundings with newly formed material despite the intense radiation environment around SagittariusA*.

IRS 3 has reached a stage near the end of its life called the asymptotic giant branch phase. Stars in this phase of life are huge, cool and luminous, and they shed gas into space with their powerful stellar winds...

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Astronomers catch massive galaxy assembling piece by piece 1.2 billion years after Big Bang

Astronomers have discovered a remarkably tiny group of six young galaxies just 1.2 billion years after the Big Bang. This may be a rare glimpse of how some of the universe’s largest galaxies formed. The paper outlining the findings was submitted to the arXiv preprint server on July 13.

Chaotic patches
The widely accepted cosmological model of the universe known as the Lambda Cold Dark Matter Model suggests that galaxies primarily form hierarchically through mergers. That means they grow piece by piece, as smaller galaxies merge over billions of years. In this context, dense regions in the early universe serve as natural laboratories to test this idea.

These dense patches, known as protoclusters and proto-groups, are young clusters of galaxies packed into a region just tens of tho...

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