Internship


I thought would be interesting to go into some detail about my research for any potential viewers who are interested in astronomy. After all, this is what I spent 40 hours a week working on.
During my last year of college I was able to participate in a NASA Space Grant internship where I studied high redshift gravitationally lensed galaxies that were less than half the age of the universe. Shown below is a massive galaxy cluster that is, relatively speaking, close to us. The left hand side color image is visible light, while the right hand side is an infrared image. On the lefthand image, the arcs of light around the center show much more distant background galaxies that are only bright and prominent because they have been magnified (gravitationally lensed) by the massive foreground cluster. Gravitational lensing is a fascinating topic by itself, so I will have to be brief. But I encourage you to click the above link and change the color!

Galaxy

Photometric (visual and infrared) observations were done using the Hubble Space Telescope, Spitzer Space Telescope, and Herschel Space Observatory. In the above image, the left hand side is from Hubble while the right hand side is from Spitzer. This research project targeted dusty, bright infrared elliptical galaxies, which are shown in the righthand image. If a galaxy was faint or lensed in the Hubble image, but bright on the righthand side, chances are we wanted to research it in greater detail. Once we selected which galaxies we wanted to focus on, spectroscopy was done with the Large Binocular Telescope’s (shown below) Multi-Object Double Spectrograph on Mt. Graham, AZ. It’s a mouthful, but the “multi-object” tells you all you really need to know: that instrument allows astronomers to point the telescope and observe not just one galaxy or star at a time, but many. For instance, we observed about twenty galaxies at once!

Credit: http://www.mpia.de/Public/LBT/lbt_feb07_gr.jpg
Credit: http://www.mpia.de/Public/LBT/lbt_feb07_gr.jpg

That experience perfectly lined me up to join an ongoing galaxy cluster survey at Gemini Observatory, which uses GMOS, the Gemini Multi-Object Spectrograph. This project is focused on observing galaxies within distant clusters (i.e. not gravitationally lensed galaxies), and comparing them to much closer galaxy cluster members in hopes of determining an evolutionary path. Unfortunately we cannot live for a billion years to watch a galaxy evolve with time, so astronomers make do by observing galaxies at different stages in their lifetimes. The goal is to determine what happens in the interim. This is similar to being tasked with observing the evolution of a human. You might look at a baby, a child, a teenager, a young adult, a middle-aged adult and an elderly person to try to fill in the gaps of how people evolve and grow. The goal of this project is to determine whether or not galaxies can passively evolve from how we observe them in their early ages to similar, nearby, much older galaxies – that is, if galaxies can evolve between those two stages without undergoing intense bursts of star formation or colliding and merging with one another.

Hawaii
Gemini Observatory

The first seven weeks of my internship were spent reducing the spectroscopic data collected with GMOS, while the next six weeks after that were spent reducing the photometric data from Hubble (making those pretty pictures). As the data turned out to be trickier than expected, I was offered an extension on my internship. Instead of staying for the initial four months, I ended up living here for almost seven! Everything about the experience was amazing, and I hope to travel much more in the future.

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