The gas in the Triangulum galaxy. This false-colour image shows the different types of gas in one of our neighbouring galaxies. The orange parts of the map show data collected from the Very Large Array, which captures most of the gas in the galaxy. The blue and black parts, found near the centre, show where that gas has cooled into clouds of molecules that are forming the next generation of stars. Erik Rosolowsky and his research group are using clues buried in these maps to unravel the connections between generations of stars. Image Credit: Erik Rosolowsky with data from the VLA (NSF/NRAO) and the Herschel Space Telescope (ESA/NASA).
"We are made of starstuff." This quote from astronomer Carl Sagan neatly sums up Dr. Erik Rosolowsky's work. Rosolowsky, an assistant professor in the Department of Physics, is studying the astronomical origins of the molecules and atoms that make up our bodies, and everything around us.
"My research is targeted at a critical link in understanding our origins from a scientific perspective. Specifically, I want to help understand how the heavy atoms that are found in our bodies move from the stars where they are forged into another solar system."
Space is far from empty. Large gas clouds exist in the areas between stars and galaxies, and it is these gas clouds that contain the molecules, specifically carbon monoxide, ammonia, and formaldehyde, that hold Rosolowsky's interest. The molecules in the gas clouds spin and rotate due to collisions with other molecules. Due to this spinning, the molecules emit radiation. Each specific molecule has its own special signature emission, and it is from these emissions that astronomers are able to detect and identify the molecules using radio telescopes. "By finding the parts of space where we see these radio waves, we can find the molecular clouds," explains Rosolowsky.
Currently, Rosolowsky is looking at molecular gas clouds in the Triangulum galaxy, a nearby spiral galaxy. "When we look at images of these spiral galaxies, they are clearly forming clouds and stars in their spiral arms. However, the mechanisms by which these arms trigger cloud formation is far less well known." As he notes, "our own galaxy is also a spiral galaxy, this may be part of how our solar system was formed."
Rosolowsky uses radio telescope facilities around the world to obtain his data. The Green Bank telescope, located in West Virginia has a diameter of 100 meters and is in almost continual use throughout the year. The Jansky Very Large Array in New Mexico is supplying the data for Rosolowsky's work on the Triangulum galaxy. Composed of 27 radio antennas, all electronically linked together, the Very Large Array operates at a much higher resolution than a single dish could.
There is an enormous amount of data from these telescopes. To help manage the very large datasets, Rosolowsky has created his own specialized software tools.
"These tools apply to many other types of similar data such as MRI images in medicine. I've applied these approaches to medical imaging data and this work was one of the cases discussed in a TED talk by my collaborator Michelle Borkin. Michelle adapted the tree diagrams we developed for studying molecular clouds to create a new method of presenting coronary artery imaging studies to doctors. This helps with heart attack prevention."