Week 6 - Delicious Science From The Kitchens of Abnormal Data
For the past month or so, I have been testing the Hubble Legacy Archive to see if it is fulfilling its job requirement of putting great scientific data out for scientists to study. One of the aspects of this was to look at stars where the energy output per unit area per unit time (i.e. flux) changes between different observations. Normally, the flux is relatively constant and stars burn at the same brightness and flux level over a short time-period spanning months and years.
When data of possible ‘variable flux’ stars are outputted by computer, it is my job to sift through to make sure that the observed variation are actually real and not caused by systematic errors in the instruments on the Hubble Space Telescope or other programming-related problems.
In order to do this, I collected all the numerical data associated with the candidate star and tried to understand the time-sequence of the variation. I then looked at the images associated with the data to make sure that nothing strange was apparent in the image and that the image looked like a ‘normal’ piece of the sky. After confirming this, I compared the flux differences of other stars in the image with that of the candidate star. If the differences were significant, I indicated that the candidate was likely a true variable star.
I found this aspect of my work extremely exciting. Although the work that I was doing was time-consuming and often involved looking at very specific details in a large number of images for hours at a time, I relished the experience. This is because I found comfort in knowing that I was one of the first people to be able to verify these variations in stellar brightness. Variable stars are very important to the study of the cosmos as they allow us to measure distances to far away galaxies and test current theories about the stellar structure. Ergo, many of these varying stars are potential candidates for future research. Indeed these could be anything ranging from elusive gamma ray bursts to eclipsing binary stars in distinct galaxies. Perhaps even something new and undiscovered. It gives me immense satisfaction to be a part of testing the Hubble Legacy Archive that is venturing into the forefront of astronomy to see the wonderful physical phenomenon associated with these variable stars that is just waiting to be explained.
About the Blogger
Rabeea Ahmed is an Astrophysics and Computer Science major at Harvard (class of 2014). She was born and raised in Pakistan, where she spent her formative years before moving to the United States for college. She's been fascinated by science since elementary school. She also enjoys roller-blading, having conversations about government and foreign cultures with my friends and absolutely loves cooking!