How do Black Holes Make a Shadow?

This is the first image of Sgr A*, the supermassive black hole at the centre of our galaxy. Credit: EHT

It’s notoriously difficult to take a picture of a black hole. But when they are surrounded by material we have an opportunity to witness the hole carved out by the event horizon. But what we see in the famous images of black holes isn’t the event horizon itself, but a magnified and enlarged version known as the shadow.

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Astronomers Go Hunting for Mysterious Q-balls

A false-color image of the Smith Cloud made with data from the Green Bank Telescope (GBT). New analysis indicates that it is wrapped in a dark matter halo. Credit: NRAO/AUI/NSF

Our universe may feature large, macroscopic clumps of dark matter, known as q-balls. These q-balls would be absolutely invisible, but they may reveal their presence through tiny magnifications of starlight.

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The James Webb Is Getting Closer to Finding What Ionized the Universe

An artist's representation of what the first stars to light up the universe might have looked like in the Cosmic Dawn. Image Credit: NASA/WMAP Science Team

Astronomers have determined that so-called “leaky” galaxies may have responsible for triggering the last great transformational epoch in our universe, one which ionized the neutral interstellar gas.

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A.I. Finds a New Way to Build Multiple-Star Systems

A false-color image of NGC 6334 from multiple telescopes. The area is believed to be a hotspot of furious star birth. Credit: S. Willis (CfA+ISU); ESA/Herschel; NASA/JPL-Caltech/ Spitzer; CTIO/NOAO/AURA/NSF

Over over 50% of high mass stars reside in multiple star systems. But due to their complex orbital interactions, physicists have a difficult time understanding just how stable and long-lived these systems are. Recently a team of astronomers applied machine learning techniques to simulations of multiple star systems and found a new way that stars in such systems can arrange themselves.

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Astronomers use Earthquakes to Understand Glitches on Neutron Stars

Simulation of a possible quadrupole magnetic field configuration for a pulsar with hot spots in only the southern hemisphere. Credits: NASA's Goddard Space Flight Center

A team of astronomers have used a model of earthquakes to understand glitches in the timing of pulsars. Their results suggest that pulsars may have interiors that are far stranger than can be imagined.

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The James Webb May See the First Stars to Appear in the Universe

An artist's representation of what the first stars to light up the universe might have looked like in the Cosmic Dawn. Image Credit: NASA/WMAP Science Team

Astronomers continue to hunt for the elusive kind of star known as Population III stars, the first stars to appear in the young universe. New research has revealed that the James Webb Space Telescope may be on the cusp of discovering them.

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The First Stars May Have Weighed More Than 100,000 Suns

The epoch of reionization was when light from the first stars could travel through the early Universe. At this time, galaxies began assembling, as did black holes. The young galaxy JADES-GS-z7-01-QU went through a star burst phase during this time, and then stopped forming stars. Credit: Paul Geil & Simon Mutch/The University of Melbourne
The epoch of reionization was when light from the first stars could travel through the early Universe. At this time, galaxies began assembling, as did black holes. The young galaxy JADES-GS-z7-01-QU went through a star burst phase during this time, and then stopped forming stars. Credit: Paul Geil & Simon Mutch/The University of Melbourne

The universe was simply different when it was younger. Recently astronomers have discovered that complex physics in the young cosmos may have led to the development of supermassive stars, each one weighing up to 100,000 times the mass of the Sun.

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