MeerKAT Archives

December 4, 2024December 5, 2024 by Brian Koberlein

MeerKAT Confirms the Gravitational Wave Background of the Universe in Record Time

A MeerKAT antenna disk in front of an illustrated view of black holes and gravitational waves. Credit: Carl Knox, OzGrav, Swinburne University of Technology and South African Radio Astronomy Observatory

The Universe is a turbulent place. Stars are exploding, neutron stars collide, and supermassive black holes are merging. All of these things and many more create gravitational waves. As a result, the cosmos is filled with a rippling sea of gravitational vibrations. While we have been able to directly detect gravitational waves since 2016, gravitational wave astronomy is still in its infancy. We have only been able to observe the gravitational ripples of colliding stellar black holes. Even then, all we can really detect is the final gravitational chirp created in the last moments of merging.

November 15, 2024November 15, 2024 by Matt Williams

Scientists Develop Technique to Create 3D Models of Cosmic Structures

Milky Way centre by the MeerKAT array of 65 radio dishes in South Africa. Credit: SAROA

For decades, astronomers have used powerful instruments to capture images of the cosmos in various wavelengths. This includes optical images, where visible light is observed, and images that capture non-visible radiation, ranging from the radio and infrared to the X-ray and Gamma-ray wavelengths. However, these two-dimensional images do not allow scientists to infer what the objects look like in three dimensions. Transforming these images into a 3D space could lead to a better understanding of the physics that drives our Universe.

In a recent study, an international team of researchers led by the Minnesota Institute for Astrophysics (MIfA) at the University of Minnesota announced the development of a new technique for radio astronomy. This first-ever technique reconstructs radio images into three-dimensional “Pseudo3D cubes” that allow astronomers to get a better idea of what cosmic structures look like. This technique could lead to an improved understanding of how galaxies, massive black holes, jet structures, and the Universe work.

June 12, 2024June 12, 2024 by Evan Gough

Astronomers Find the Slowest-Spinning Neutron Star Ever

This artist's illustration shows CSIRO’s ASKAP radio telescope with two versions of the puzzling, newly-discovered celestial object: neutron star and white dwarf. Image Credit: Carl Knox, OzGrav

Most neutron stars spin rapidly, completing a rotation in seconds or even a fraction of a second. But astronomers have found one that takes its time, completing a rotation in 54 minutes. What compels this odd object to spin so slowly?

May 30, 2024May 30, 2024 by Mark Thompson

Hot Gas is Being Vented Away from the Center of the Milky Way

X-Ray Data Revealing Jets at the Center of the Milky Way Credit: X-ray: NASA/CXC/Univ. of Chicago/S.C. Mackey et al.; Radio: NRF/SARAO/MeerKAT; Image Processing: NASA/CXC/SAO/N. Wolk

Studying gas in the Universe is no easy task. We often look to ‘non-visible’ wavelengths of the electromagnetic spectrum such as X-rays. The Chandra X-Ray observatory has been observing a vent of hot gas blowing away from the centre of the Milky Way. Located about 26,000 light years away, the jet extends for hundreds of light years and is perpendicular to the disk of the Galaxy. It is now thought the gas has been forced away from the centre of the Milky Way because of a collision with cooler gas lying in its path and creating shockwaves.

January 26, 2024January 26, 2024 by Mark Thompson

Another Asteroid Discovered Hours Before it Impacts the Earth

What were you doing last Saturday? As it turns out, I was doing something rather unexciting… Trying to fix my washing machine (I did – in case you are interested). At the same time, Hungarian geography teacher by day and asteroid hunter by night Krisztián Sárneczky was out observing and detected a small asteroid which it transpired was on a collision course with Earth!

December 3, 2022December 5, 2022 by Scott Alan Johnston

One of the World's Biggest Radio Telescopes is Hunting for Signals From Extraterrestrial Civilizations

Breakthrough Listen, a privately funded project seeking evidence of extraterrestrial intelligence, has started operations on the MeerKAT radio telescope array in South Africa. Over the next two years, the team will search over a million nearby stars, expanding the number of targets observed by a factor of 1000.

June 2, 2022June 2, 2022 by Matt Williams

A Pulsar has Been Found Turning so Slowly Astronomers Didn't Even Think it was Possible: Once Every 76 Seconds

Astronomy is progressing rapidly these days, thanks in part to how advances in one area can contribute to progress in another. For instance, improved optics, instruments, and data processing methods have allowed astronomers to push the boundaries of optical and infrared to gravitational wave (GW) astronomy. Radio astronomy is also advancing considerably thanks to arrays like the MeerKAT radio telescope in South Africa, which will join with observatories in Australia in the near future to create the Square Kilometer Array (SKA).

In particular, radio astronomers are using next-generation instruments to study phenomena like Fast Radio Bursts (FRBs) and neutron stars. Recently, an international team of scientists led by the University of Manchester discovered a strange radio-emitting neutron star with a powerful magnetic field (a “magnetar”) and an extremely slow rotational period of 76 seconds. This discovery could have significant implications for radio astronomy and hints at a possible connection between different types of neutron stars and FRBs.

March 24, 2022March 24, 2022 by Brian Koberlein

New Radio Images of Bizarre “Odd Radio Circles” Which are Vastly Bigger Than the Milky Way

Artist depiction of an Odd Radio Circle. Credit: CSIRO

In radio astronomy, circle-shaped objects are fairly common. Since diffuse ionized gas often emits radio light, objects such as supernova remnants, planetary nebulae, and even star-forming regions can create circular arcs of diffuse gas. But in 2019 astronomers began to discover radio circles they couldn’t explain, in part because they are so large.

February 20, 2022February 20, 2022 by Matthew Cimone

Imaging the Galaxy’s Centre in Unprecedented Detail Reveals More Mysterious Filaments

The inner 600 light years of our galaxy is a maelstrom of cosmic radiation, turbulent swirling gas clouds, intense star formation, supernovae, huge bubbles of radio energy, and of course a giant supermassive black hole. This bustling downtown of the Milky Way is a potential treasure trove of discovery but has been difficult to study as the galaxy’s central regions are obscured by dust and glaring radiation. But a new image of this region with unprecedented detail reveals more than we’ve ever seen before. We find some familiar objects like supernovae but also some mysterious structures – gaseous filaments dozens of light years long channeling electrons at near light speed.

Behold, the galaxy’s centre as never seen before:

The new MeerKAT image of the Galactic centre region is shown with the Galactic plane running horizontally across the image. Many new and previously-known radio features are evident, including supernova remnants, compact star-forming regions, and the large population of mysterious radio filaments. Colours indicate bright radio emission, while fainter emission is shown in greyscale. Credit: I. Heywood, SARAO. Image description: SARAO

October 18, 2021October 18, 2021 by Evan Gough

What’s Causing the Mysterious Radio Waves Coming From the Center of the Milky Way?

An artist's impression of ASKAP J173608.2-321635, the mysterious radio source at the center of the Milky Way. Image Credit: Sebastian Zentilomo.

The center of the Milky Way is a mysterious place. Astronomers think there’s a supermassive black hole there, though it could be dark matter instead. The region is densely packed with stars, dominated by red giants. And because of all the dust between Earth and the galactic center, we can’t see anything with visible light, ultraviolet light, or low-energy x-rays.

But we can detect radio waves, and there are some unexplained ones coming from the center of the galaxy, and adding to the mystery.