The Surprising Source of Radiation Coming From Black Holes

A visualization of how turbulent plasma moves through a black hole accretion disk threaded with strong magnetic fields. Image credit: Jani Narhi.
A visualization of how turbulent plasma moves through a black hole accretion disk threaded with strong magnetic fields. Image credit: Jani Närhi.

Black holes are famous for sucking in everything that crosses their event horizons, including light. So, why do astronomers see energetic radiation coming from the environment of a black hole in an X-ray binary system? It’s a good question that finally has an answer.

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This Ancient Galaxy Merger Will Produce a very Luminous Quasar

This illustration depicts two quasars in the process of merging. There are many unanswered questions around galaxy mergers and the quasars that can result. Image Credit: NOIRLab/NSF/AURA/M. Garlick)

In the contemporary Universe, massive galaxies are plentiful. But the Universe wasn’t always like this. Astronomers think that galaxies grew large through mergers, so what we see in space is the result of billions of years of galaxies merging. When galaxies merge, the merger can feed large quantities of gas into their centers, sometimes creating a quasar.

Much of this is theoretical and shrouded in mystery, but astronomers might have found evidence of a galaxy merger creating a quasar.

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Catch a Fall Feast of Lunar Occultations in September

Occultation
The Moon occults Saturn in August 2024. Image credit: Roger Hutchinson.

September offers a number of fascinating lunar occultation events worldwide.

Chances are, there’s one near you this month. The Moon is certainly busy in September, as its passage covers up (occults) multiple celestial objects worldwide. If skies are clear, you may just get a chance to see one of these events listed below, as the Moon blocks out a star, planet or star cluster.

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A Global Color Map of Mars, Courtesy of China’s Tianwen-1 Mission

China’s first Mars global color image map. Credit and ©: Science China Press

In July 2020, China’s Tianwen-1 mission arrived in orbit around Mars, consisting of six robotic elements: an orbiter, a lander, two deployable cameras, a remote camera, and the Zhurong rover. As the first in a series of interplanetary missions by the China National Space Administration (CNSA), the mission’s purpose is to investigate Mars’s geology and internal structure, characterize its atmosphere, and search for indications of water on Mars. Like the many orbiters, landers, and rovers currently exploring Mars, Tianwen-1 is also searching for possible evidence of life on Mars (past and present).

In the almost 1298 days that the Tianwen-1 mission has explored Mars, its orbiter has acquired countless remote-sensing images of the Martian surface. Thanks to a team of researchers from the Chinese Academy of Sciences (CAS), these images have been combined to create the first high-resolution global color-image map of Mars with spatial resolutions greater than 1 km (0.62 mi). This is currently the highest-resolution map of Mars and could serve as a global base map that will support crewed missions someday.

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Gravitational Wave Observatories Could Detect Primordial Black Holes Speeding Through the Solar System

Artist illustration of primordial black holes. NASA's Goddard Space Flight Center

Cosmologists have long hypothesized that the conditions of the early universe could have caused the formation of black holes not long after the Big Bang. These ‘primordial black holes’ have a much wider mass range than those that formed in the later universe from the death of stars, with some even condensed to the width of a single atom.

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By Watching the Sun, Astronomers are Learning More about Exoplanets

Illustration of the Sun seen from Mercury

Watching the Olympics recently and the amazing effort of the hammer throwers was a wonderful demonstration of the radial velocity method that astronomers use to detect exoplanets. As the hammer spins around the athlete, their body and head bobs back and forth as the weight from the hammer tugs upon them. In the same way we can detect the wobble of a star from the gravity of planets in orbit. Local variations in the stars can add noise to the data but a team of researchers have been studying the Sun to help next-generation telescopes detect more Earth-like planets. 

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Coronal Loops-Digital Art Combination Captures Power of the Sun, Rendered by Andrew McCarthy

A composite image comprised of the Sun's surface, corona, and digitally-added coronal loops rendered by Andrew McCarthy. (Credit: Andrew McCarthy)

Our Sun is one of the most fascinating objects in the universe and photographing it with specialized equipment to capture its splendor and beauty has become increasingly more common around the world. This is most evident with the work obtained by renowned astrophotographer, Andrew McCarthy (@AJamesMcCarthy), who owns Cosmic Background Studios in Florence, Arizona.

On July 27, 2024, McCarthy posted an image of the Sun on X (formerly known as Twitter) taken with his specialized equipment designed to safely photograph our life-giving star, which revealed active coronal loops and plasma within the solar chromosphere that are some of the many intriguing features of the Sun. However, McCarthy is quick to mention in his post that this image isn’t entirely genuine, but a combination of several attributes.

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Estimating the Basic Settings of the Universe

This snapshot compares the distribution of galaxies in a simulated universe used to train SimBIG (right) to the galaxy distribution seen in the real universe (left). Bruno Régaldo-Saint Blancard/SimBIG collaboration

The Standard Model describes how the Universe has evolved at large scale. There are six numbers that define the model and a team of researchers have used them to build simulations of the Universe. The results of these simulations were then fed to a machine learning algorithm to train it before it was set the task of estimating five of the cosmological constants, a task which it completed with incredible precision. 

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Dark Matter Could Have Driven the Growth of Early Supermassive Black Holes

An image from the Event Horizon Telescope shows lines of polarization, a signature of magnetic fields, around the shadow of the Milky Way's central supermassive black hole. Astronomers want to know how massive black holes like this one formed early in cosmic history. (Credit: EHT Collaboration)
An image from the Event Horizon Telescope shows lines of polarization, a signature of magnetic fields, around the shadow of the Milky Way's central supermassive black hole. Astronomers want to know how massive black holes like this one formed early in cosmic history. (Credit: EHT Collaboration)

The James Webb Space Telescope (JWST) keeps finding supermassive black holes (SMBH) in the early Universe. They’re in active galactic nuclei seen only 500,000 years after the Big Bang. This was long before astronomers thought they could exist. What’s going on?

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If Gravitons Exist, this Experiment Might Find Them

It’s thought that gravity consists of minute quantum building blocks called gravitons, but so far they have been too elusive to observe. A new result from Pikovski’s Research Group now shows that next-generation quantum sensors can catch a single one.

There are four fundamental forces in the Universe; strong, weak, electromagnetic and gravity. Quantum theory explains three of the four through the interaction of particles but science has yet to discover a corresponding particle for gravity. Known as the ‘graviton’, the hypothetical gravity particle is thought to constitute gravitational waves but it hasn’t been detected in gravity wave detector. A new experiment hopes to change that using an acoustic resonator to identify individual gravitons and confirm their existence. 

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