After years of work and a huge hype, researchers working with the Horizon Telescope project of the Event finally revealed the first image of a real black hole this week. However, the relatively low resolution image was fantastic, and the fact that scientists have been able to capture an image of the black hole at a distance of approximately 55 million light-years away is absolutely mind-boggling.
But wait, we live in the galaxy of the Milky Way, and at the center of this is what scientists believe is a supermbadive black hole called Sagittarius A *. Our galaxy is only between 150,000 and 200,000 light years in diameter, would not it have been much easier to photograph our own black hole?
That's a question I've seen several times on social networks since the first black hole photo began to circulate, and it's a good one. It would make sense to capture a picture of the black hole closest to Earth, especially if we want to see it in great detail. Unfortunately, Earth, and the vast majority of planets in the galaxy, are simply not in the correct position to see the black hole of our galaxy.
The Milky Way is a spiral galaxy with long arms filled with hundreds of billions of stars, and is arranged like a flat disk. If you had to look at the entire galaxy from your face, you would quickly see our dilemma:
The point labeled "Sun" is where our solar system resides in the galaxy, riding the edge of one of the long, curved arms of the Milky Way. From our point of view, looking towards the center of the galaxy, it looks something like this:
Trying to see the black hole of our galaxy is like trying to see the center of a vast forest while standing along its edge. There are too many things on the road, including stars, planets, gas and dust. To hope to see our own black hole, we would have to send a ship to tens, or even hundreds of thousands of light-years away, allowing it to see the Milky Way from its face instead of its side.
Therefore, the Event Horizon Telescope team did the following, which was to look for a galaxy with the correct orientation to be observed from Earth, and Messier 87, and its black hole known as M87, proved to be a perfect candidate.