MeerKAT Spots Bubbles

Alltheus has been told that the origin of structures and objects in the universe is a critical question. Gravity is the glue with which the universe builds large structure as mass distorts stiff but flexible spacetime. The number and variety of objects in the universe is partly determined by gravity’s effect on the small differences in matter distribution from when the Big Bang occurred. Matter will try to fall into the bowls of matter-distorted spacetime but matter is compressed and heats up as it falls into these sinks, increasing the pressure to expand. Physicist James Jeans was  amongst the first to provide a basis for understanding how nebulae balance the opposing forces of gravity and gas pressure.

Understanding how galaxies form and ‘live’ around magnetic fields, flow motions in the nebulae and material distribution is a complex task. A study head authored by Dr Ian Heywood of University of Oxford’s Department of Physics is important in this regard inspired the design.

The study, published in Nature in September 2019, helps provide more insight and understanding of galactic formation and their evolution as well as the nature and impact of matter. It describes an hourglass-like feature, with a span of about 140 by 430 parsecs (about 456 x 1400 light years) dwarfing other features near the galactic centre. The design exaggerates the morphology of the twin radio-emitting towering bubble-like features projecting above and below the Milky Way’s galactic plane and tries to playfully capture the study’s use of the South African Radio Astronomy Observatory MeerKAT telescope with the picture of a meerkat perched on the African continent looking up towards the galactic centre. These newly discovered features may also be related to another galactic phenomenon known as the gamma-ray emitting Fermi bubbles according to the US National Radio Astronomy Observatory’s Dr William Cotton.

The observations are helping to unlock the record of how the supermassive Sagittarius a* black hole and our galaxy has evolved. The paper suggests that some violent energetic eruption millions of years ago punched through the interstellar medium in both directions and may be the origin of the magnetized filaments that produce the radio emissions. The team used the MeerKAT telescope to achieve the difficult task of imaging the synchrotron radiation through the dense dust clouds at the Milky Way’s centre providing a foretaste of the possibilities of the Square Kilometre Array (SKA), not to mention the much touted James Webb telescope.

The year 2019 has seen the publication of the very first photograph of a supermassive black hole of M87 from the well choreographed Event Horizon Telescope collaboration across the globe. We can also now “see” the faint cosmic symphony of rippling spacetime from colliding black holes and neutron stars using fantastic laser interferometry devices (LIGO, VIRGO etc) that provide a whole new way for observing the cosmos. Having the space bound LISA (Laser Interferometry Space Antenna) gravitational wave observatory, the Earthbound telescopes across the electromagnetic spectrum and the necessary computing power to capture, process and store the data may, in combination, make the 21st century a golden one for astronomy – related sciences if we can avoid the difficulties that may be created from launching too many satellites into orbit

In the meantime Dr Heywood’s team is to be congratulated for successfully completing the immensely difficult task of teasing out the “bubble” images from the background “noise”, building on previous work and developing new techniques that will be increasingly needed for using the enormous amounts of data produced by the SKA, CHIME (the Fast Radio Burst-detecting Canadian Hydrogen Intensity Mapping Experiment) and other observational tools.

The astronomical profession is pretty confident that most of the universe’s matter is dark with normal, “light” baryonic matter making up only about 5% of the universe’s mass-energy budget. Our wonderful technological progress to date is largely down to using 5% of the universe so imagine the possibilities still to come as we begin to truly understand the other 95% of the universe and better understand the origins of the universe’s structure and the objects within it! (The chemist Andreas Sella is eagerly anticipating – tongue firmly in his cheek - a whole periodic table of dark matter! 

 

References:

Gravity’s Engines: How Bubble Blowing Black Holes Rule Galaxies, Stars, and Life in the Cosmos

Caleb Scharf, Scientific American 2012

 

Some Related Podcasts

What are fermi bubbles? Daniel & Jorge Explain the Universe, 3 October 2019

Towering Radio Bubbles Discovered At The Galactic Centre  Series 22, Episode 69, Sept. 18, 2019 SpaceTime with Stuart Gary

The Monster at the Centre of the Milky Way Is Getting Active Series 22, Episode 70, Sept 2019 SpaceTime with Stuart Gary

The Amazing Computing Power of the Square Kilometre Array Series 22, Episode 52, July 2019

SpaceTime with Stuart Gary

Thousands of Black Holes at The Center of the Milky Way? Series 21, Episode 29, SpaceTime with Stuart Gary

Black Holes Don’t Suck Cosmic Vertigo 14 April 2017 with Dr.s Alan Duffy and Amanda Bauer.