Supermassive black holes are pretty typical in our world, sitting at the hearts of the majority of large galaxies. Their powerful gravitational fields permit them to suck and obliterate items that get too near them. And while they consume most of this celestial matter, a small portion escapes the black hole and blasts out into space. These emissions, called jets, emit radio waves and travel at almost the speed of light.
And even though we can detect some of Sgr A*’s radio emissions from Earth, studying it’s easier said than done. A foggy cloud of hot gas has prevented astronomers from making sharp pictures of this supermassive black hole Sagittarius A*, casting doubt on its own true character. Astronomers have incorporated the powerful ALMA telescope in northern Chile to a global network of radio telescopes to peer through this fog, but the origin keeps the emission region is so small that the origin might actually point straight at Earth.
Using the monitoring technique of very long baseline interferometry (VLBI) at a frequency of 86 GHz, which combines many telescopes to produce a digital telescope the size of the planet, the team succeeded in mapping out the specific properties of this light scattering blocking our view of Sagittarius A*. The removal of most of the scattering effects has generated the very first image of the surroundings of the black hole.
But lately, a group of investigators managed to isolate this radio emission using very long baseline interferometry — a technique that combines multiple telescopes to create a massive, extremely powerful one. Using 13 radio telescopes from around the world, they removed the effects of the hot gas to find a better image of the jets’ emission than previously.
They discovered that it’s coming from a symmetrical source, which lines up well with the “jet” concept since they blast from black holes in opposite directions. They also discovered that the emission is a lot narrower than they thought. So narrow, in reality, that it’s coming from only one 300 millionths of a degree — suggesting that it is aimed almost directly at Earth.
By luck of the draw, this means we might have a direct view into one of our black hole defining traits. And do not worry about the jet really blasting us because as much as we understand, being in its own line of sight doesn’t place us in any danger. If anything, it might allow us to study the jet in impeccable detail and shed light on Sgr A*’s cryptic nature.