New Mass Estimate for the Milky Way

In the article, “New Mass Estimate for the Milky Way,” the author first begins to talk about how a group of astronomers  basically low balled the estimate for the mass of our Milky Way. Than the author  explains to us why the estimate was low balled and tells us that it is hard to measure something when you are inside of it , also the visibly of it makes it hard . The author exemplifies this by saying “It’s also quite difficult to measure something you can’t see, and invisible dark matter dominates the Milky Way’s mass.” Next the author talks about a scientist choosing to use globular clusters. However the author disproves the clusters by explaining how they still will not be as accurate as the actually mass of the Milky Way. However after all of these limitations to the accuracy of finding the true mass, scientists made due with what they know, Eadie and her team estimated that the Milky Way contains between 600 and 750 billion suns worth of mass within 600,000 light years. This is a lot lower than previous estimates which set the mass of the Milky Way at about a trillion suns.

Objective 15 is to be able to describe the structure and size of the Milky Way galaxy. This article relates to this objective because it discusses the strategy of using globular clusters to estimate the size of the galaxy. The Milky Way galaxy consists of a thin disk about 100,000 light years in diameter with a central bulge and a spherical region called the halo. This halo surrounds the entire disk. Most of the galaxy’s bright stars reside in its disk. According to the textbook, the disk contains most of the gas and dust of the interstellar medium, while the halo contains only a small amount of hot gas and virtually no cold gas. The most important stars in the halo are found in about 200 globular clusters of stars.  Also, the power point slides during class stated that the orbit of clusters can be used to estimate the mass of the galaxy, just like what the astronomers in this article are doing. Lastly, In order to view the galaxy from within, we measure the distance to globular clusters or measure distribution of hydrogen gas in the disk.

I really found this article to be quite intriguing. The reason I say this is because this article is not like most articles where the author agrees with everything in the writing . In this article the author disproves some of the scientists methods to find the actually mass of the milky way which actually gets the authors point across better and helped me understand greatly how it is nowhere near easy to accurately estimate the mass of the milky way.  Therefore , I found this article very informative and very easy to understand which helped me enjoy it over previous articles I have read.


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