The white dots in this image are not stars, or galaxies. They’re black holes.

At first glance, this image appears to be of a collection of 25,000 stars. But there are no stars being photographed here. These are all super-massive singularities at the center of galaxies. That’s right. Every single glowing dot you see is a supermassive black hole at the center of every galaxy in the image. The stars of those galaxies are not visible in this image because the image only captures ultra-low radio wavelengths.

Gravitational singularities or known by their more common nomenclature, black holes are invisible to conventional photography. With gravities so strong, not even light energy can escape them, they are impossible to photography under normal conditions. When we try to view singularities with normal light, the only thing we are able to see is the gravitational lensing effect, the distortion of light behind them as they bend light near their even horizons. This means that we see the area they obscure with their intense but tiny gravitational field by distorting space time (and the light traversing it).

These photos are achieved by watching the only radiation capable of escaping them, very long wave radiation which occurs when matter is falling into black holes from other nearby stars, nebula or other matter being destroyed as it crosses the event horizon, the region around a black hole where once matter or energy crosses this region, it cannot escape.

“What makes the above image so special is that it covers the ultra-low radio wavelengths, as detected by the LOw Frequency ARray (LOFAR) in Europe. This interferometric network consists of around 20,000 radio antennas, distributed throughout 52 locations across Europe.”

The radiation being redirected as long wave radiation from objects crossing the event horizon is captured with extended exposures over very long periods until a star-like image is created. This process is very difficult to achieve, often requiring multiple receiving stations across the globe and digital integration of those images.

“Currently, LOFAR is the only radio telescope network capable of deep, high-resolution imaging at frequencies below 100 megahertz, offering a view of the sky like no other. This data release, covering four percent of the Northern sky, is the first for the network’s ambitious plan to image the entire Northern sky in ultra-low-frequencies, the LOFAR LBA Sky Survey (LoLSS).”

The visual result, however is astounding, revealing the Universe is awash in such singularities, with at least one super-massive black hole for every single major galaxy in the sky. Yet, we still have much to discover as the ionosphere of the Earth’s atmosphere is opaque to ultra-low frequency radio waves below 5 megahertz, sometimes reflecting them back into space.

This new science requires coordination between thousands of receiving stations, computer processing power, and data integration coming from tens of thousands of receiving stations and will likely take years to map the remaining 96% of the Northern hemisphere.

As science gets better at exploring their means of detection, it is likely new observations of the habits of singularities will lead to new discoveries and reveal new perspectives on the nature of our own galaxy.

-30-