The Mysteries of Space Dust

Have you ever looked up at the sky during a very clear night and wondered what is really out there? The expansiveness of the universe continually boggles my mind. In the hopes of learning more about the star dust from whence we all came I decided to search for an astronomy internship for the summer. I was fortunate enough to land a research project under Professor Daniel Wang in the Astronomy Department at the University of Massachusetts in Amherst.

For this internship I am studying the dust attenuation curve, which determines the amount of interstellar absorption and scattering of light as a function of wavelength, in the central region of the nearby Andromeda galaxy. The determination of the attenuation curve is critical for astronomers to probe the intrinsic properties of galaxies, as well as interstellar dust. Existing studies have shown evidence that the attenuation curve is steeper in this galaxy than in the Milky Way. Additionally, the strong 2175 Angstrom attenuation bump appears to vary among different dusty clumps in the region. In order to better understand these important characteristics of the attenuation properties and their spatial variation, we have obtained spectroscopic data from the Hubble Space Telescope STIS observations of two prominent dusty clumps. Results from this study compared with previous multi-wavelength data will further our knowledge with regard to what causes the steep slope of the attenuation curve in the region, and how the variation of the curve depends on the properties and environments of the clumps. This research is important for us to use the central region as a laboratory to explore how high-energy activity in a galactic nucleus affects its environment.

Thus far, I started processing the Hubble Space Telescope data to extract spectra, and soon I hope to confront them with models to better understand the dust properties in the extreme nuclear environment of the galaxy. My work focuses on the dusty clumps within the blue box, as seen in the figure above. While working on this project I have learned a great deal about astronomy, data analysis, programming, and the patience required for conducting research. Every day my goal is to accomplish a few small things so that over time these successes will add up towards a significant result.