How will it impact astronomy?

If the astronomy community were to list a “must-have” dream list, “direct observation of black holes and their surroundings with angular resolution equivalent to the event horizon” would certainly be on it. Why?

Black holes are the most special and fascinating celestial bodies in the universe. A huge amount of matter is squeezed into an extremely small space, making this extremely rule-breaking celestial body very strong in gravity. The “event horizon” surrounding the black hole is like a boundary of the black hole. Anything that enters this boundary cannot escape the black hole’s gravity grip, and even light is no exception - black holes absorb all the light we use to observe them. So how can we observe black holes?

Astronomers can still learn a lot through bright luminous matter around black holes.

Because the gravity of black holes will accumulate matter around them, there is usually an accretion disk around them. The accretion disk is extremely hot and bright. The bright accretion disk and the completely non-reflective black hole form a contrast of brightness or darkness, so we shall be able to see a silhouette of the event horizon against the accretion disk, as known as the shadow of a black hole. By observing the shadow, we can prove the existence of the associated black hole.

In addition to directly obtaining images of supermassive black hole shadows, obtaining images of the environment around black holes is also a rare opportunity to verify whether general relativity applies to strong gravitational fields. For a century, general relativity has passed many tests without exception, proving that what its predictions are correct. However, astrophysicists believe that these cases were not under conditions of strong gravitational fields, so direct observation is necessary.

Although it is now widely recognized in the astronomical community that there is a supermassive black hole at the center of each galaxy, the mechanisms inside a black hole are still difficult to explain. Astronomers have to ask why there is a supermassive black hole at the center of each galaxy? We also know that black holes have a significant impact on galaxy formation and evolution, so it is necessary to understand the relationship between black holes and host galaxies and even with the universe, including understanding mechanisms such as material formation and accretion near black holes, accretion disk formation, jet acceleration, and black hole physics. Perhaps when we clarify why the energy conversion rate of black holes is so high, it will also help us develop energy science?

Each of these challenges human knowledge limits and contains various potentials to advance future scientific development and promote large-scale research for human life.