More Evidence for Coming Black Hole Collision

Black holes are ultra-dense objects that suck in everything from stars, gases, and even light. Each galaxy has at least one supermassive black hole and when these galaxies coalesce, the black holes are forced to orbit each other. In most cases, the black holes cannot get close enough to merge because the gravity of nearby planets and stars hold them back; however, in a galaxy 3.5 billion light-years from earth, an unusual event has developed. Last year, a team of scientist discovered two massive black holes weighing more than a billion suns combined, set to converge with each other. There are not enough planets or stars nearby to hold them back, and when these two black holes will meet they will release as much energy as 100 million supernova explosions in the form of gravitational waves. For reference, supernova’s have so much energy that for a brief period they outshine the entire galaxy. The evidence for this collision was a flickering coming from the center of that galaxy, specifically from a quasar, a bright mass of light and energy, called PG 1302-102. Recently, new evidence also was discovered to back this prediction. Daniel D’Orazio of Columbia University and his colleagues predicted that light coming from the quasar, is actually coming from a disk of gas surrounding one of the black holes. They predicted that the closer the black holes come together, the more light will be emitted from the disk and accelerated by the Doppler Effect. They also predicted that the variation would be greater in ultraviolet light, which they later confirmed from analyzing their data. The model D’Orazio and his colleagues came up with suggest the black holes are only 200 billion miles away and would collide within the next 100,000 years. But, because the galaxy is so far away from earth, it is possible that the collision has already occurred, and the effects would only reach us in the future.

This article and the research shown in it are important for understanding the characteristics of black holes and collecting more evidence to back the theory of general relativity. Black holes are a mystery to scientists, simply because they can’t be directly seen and there are many theories as to what happens when something approaches a black hole. There are a lot of observations and data explaining some of the behaviours of black holes, but discoveries such as these help reveal more of the mystery. Similarly, general relativity has passed experiments, discoveries, and observations, but “some of its predictions can be tested only in the most extreme gravitational environments, namely black holes.” Essentially, the more data we collect about black holes and the gravity waves they often release, the more we will learn about “the secrets of gravity.”

This article was well-written, but I had a few issues with the way it explained a lot of the evidence. The article assumed that the reader had general knowledge of the different types of stars, which was sometimes annoying because I had to search up a lot of terms. The author was also not clear with explaining what exactly the new data proved and why it was important to confirming the theory of the collision. I had to re-read the part explaining the evidence they discovered because it was confusing and disjointed. Overall though, the author did explain some essential parts of black holes, which was nice since it cleared up a lot of misconceptions, I just wish he had been clearer when explaining the evidence. 

Overbye, Dennis. "More Evidence for Coming Black Hole Collision." The New York Times. The New York Times, 21 Sept. 2015. Web. 22 Sept. 2015.

http://www.nytimes.com/2015/09/22/science/space/more-evidence-for-coming-black-hole-collision.html?action=click&contentCollection=science&region=rank&module=package&version=highlights&contentPlacement=6&pgtype=sectionfront