How Were Scientists Able to Photograph a Black Hole Where Not Even Light can Escape?
A Captivating Photographic Undertaking of a Black Hole.
The term black hole is something you might have heard before. This term has been thrown around in conversations and many movies, especially Sci-Fi movies like Interstellar and Star Trek. But each movie has a different depiction of the black hole. Wouldn’t it be captivating to see what a black hole looks like in reality? In April of 2017, the first-ever picture of a black hole was taken. Maybe it doesn’t look spectacular, but consider the fact that black holes by nature are invisible. This is simply because a black hole’s gravity is so strong that not even light can escape. If light can’t escape, then it cannot reach our eyes or in this case, the telescope. For many years, astronomers thought that a picture of a black hole was impossible because of this phenomenon. So how did they do it? It started with a small team of innovators and eventually a telescope, unlike anything the world had ever seen.
The Event Horizon Telescope
A single telescope isn’t capable of getting a picture of a black hole, simply because the telescope is too small. To photograph a black hole, we would need a telescope which is the size of the earth. This is impossible, so scientists found their way around it. Instead, they put eight telescopes around the world and synchronized them using atomic clocks. It is a bit like having a shattered mirror and taking those fragments and placing them all around the world. Then collect images on those fragments or data in our case. Finally, take all those fragments and put them together to get the bigger and complete image. This telescope is called the Event Horizon Telescope, which observes radio sources associated with black holes.
The Type of Black Hole
The black hole that was photographed was a supermassive black hole. Its mass is 6.5 billion times that of our sun and it is located in the Messier 87 galaxy which is about 500 million trillion km away. That is 5 with 15 zeros behind it! 5,000,000,000,000,000 km
The Accretion Disk and The Event Horizon
The red part of the image is what scientists call the accretion disk. An accretion disk forms when a star gets too close to a black hole and the black hole’s gravity sucks it in. In simple terms, the black hole is eating the star and the red part is the star’s matter. The accretion disk is what makes the black hole visible. This image proves that black holes look and behave how astronomers predicted them to be. This is because black holes have an edge. This edge is what scientists call the event horizon. The event horizon is a place of no return. Once you go past it nothing can escape. This is why everything past the event horizon is black because the light that went past the event horizon will never come back and will be undetectable, thus creating an absence of light or black.
The Future
Now astronomers are looking at photographing Sagittarius, which is a black hole at the center of our galaxy, but this will be much harder because Sagittarius is a smaller black hole. The photograph of a black hole shook the world because it turned what was considered a theory and put it into reality. The field of physics helps us predict the world around us with such high accuracy, whether it be for ordinary forces or the quantum and cosmic levels. This is why many young thinkers like me have been inspired to pursue this field because it is constantly evolving.
