In the article “Astronomers find a puzzling pair of merging galaxies” , the author begins to talk about how the merging of galaxies is very common and merging is the reason we have our much larger galaxies in the universe today. Than the author goes to explain how astronomers discover merges by using snapshots overtime because of the difficulty to discover these merges. Therefore, the difficulty of discovering these merges comes from time itself . The author states, “but because mergers take, on average, about 2 billion years or so to complete it is challenging,”. This article then starts to talk about a recently observed galaxy merger with a galaxy called “Was 49”. While observing this galaxy astronomers found something they never expected “We didn’t think that dwarf galaxies hosted supermassive black holes this big. This black hole could be hundreds of times more massive than what we would expect for a galaxy of this size”. Than the author goes on to explain how normal galaxy mergers actually merge. The author states as galaxies merge, so too do their central supermassive black holes. This process often funnels dust and gas into the centers of the galaxies, turning their nuclei “on” as AGN.” However, for the particular merger it was the opposite because as the author states “Normally, the material disturbed during a galaxy merger should funnel into the larger galaxy’s black hole, making it the more luminous AGN.” Was 49 did the opposite. Although, Was 49 did the opposite as expected astronomers gained new insight how supermassive black holes form and grow in such systems.
This article corresponds to Objective 16, “being able to compare the Milky Way galaxy to other galaxies”, because now after reading it I can compare the Milky Way galaxy with the ones from this article using the information I obtained from our power point slides during class, workbook pages, and reading the textbook that correlates with this chapter. To start, there are three main types of galaxies. First we have the spiral galaxy, which is like our own Milky Way. Then we have the elliptical galaxy, which is a galaxy having an approximately ellipsoidal shape and a smooth, nearly featureless brightness profile. Then lastly, the irregular galaxy which is a galaxy with no distinct shape . We saw these different types of galaxies when we were working in our workbook with the people around us when we had to compare and categorize the different galaxies in one of the exercises. Next, I am able to compare the Milky Way to “Was 49a” from the article because the Milky Way is a spiral shaped galaxy that is a flat disk with arms. “Was 49a” is also a flat disk galaxy. There are also very large differences between spiral galaxies, like the Milky Way, and elliptical ones. Spiral galaxies are big galaxies that have large quantity’s of gas and dust. They also have a large amount of active star formations which means many young stars which means a lot of blue stars that can give the galaxy a blue like color. Elliptical galaxies have much more older stars with little gas, dust, and star formations unlike a spiral galaxy. Therefore, the will receive more of a red color. Since the article does not identify more features of the galaxies I can only assume by the information given that “Was 49a” is a spiral galaxy since it is disk shaped and also that “Was 49b” is an irregular galaxy due to it being a dwarf. Therefore, I can compare the Milky Way because it is one of the main galaxy types like the ones from the article are.
I found this article very interesting because I was able to take away information I would never think of in the past. For example, I found it really cool to learn that galaxies can actually collide together like in the article . Lastly , I enjoyed this article because i understood the objective greatly so when reading the article I was easily able to connect it to everything we learned and did in class.