I am an Assistant Professor of Astronomy and Astrophysics I study our own Milky Way galaxy to find out how and why it evolved to its present state. The evidence is that our Galaxy is a fairly typical spiral galaxy. That means that by studying our home in the universe, we can learn a lot about the evolution of other spiral galaxies like it. We can also use the story of our own Galaxy to help interpret observations at high redshift, where we can catch galaxies in the process of forming.
There are lots of observational and theoretical reasons why we think Galaxies like the Milky Way are created through merging and accretion of smaller systems. We can use the Milky Way to help answer some basic questions about how that process works.
Because we live in the middle of it, we see stars in the Galaxy spread over the whole sky. You can see that for yourself when you look at the Milky Way stretched across the sky on a clear night. What you are looking at is the disk of our Galaxy, edge-on, from the sun's position near one edge. So if we want a big-picture view of the Galaxy, we need large-area surveys that cover an appreciable fraction of the sky.
Two such surveys I have worked on and with are the Sloan Digital Sky Survey (SDSS) and SEGUE, the Sloan Extension for Galactic Understanding and Exploration. Both of these use imaging in five filters and moderate-resolution spectroscopy to map out the structure (where the stars are) and stellar population content (where stars of different ages and metal-content are located). The SDSS was designed primarily to map the local universe, so it looked up out of the plane of the Galaxy. In the process of doing that extragalactic survey, it mapped about one quarter of the sky around the North Galactic pole. SEGUE is designed specifically to cover a larger range in Galactic latitude, reaching much closer to the plane of the Galaxy, in order study the Milky Way. You can see a map of how the SDSS and SEGUE cover the sky here.In order for the SDSS and SEGUE surveys, or any other astronomical observations, to happen, we first need to have instruments that can see fainter objects and over a larger range in wavelength than our eyes can see. I've worked on a few instruments as a graduate student and postdoc, and plan to build more in the future.
A description of the imaging camera for the SDSS, which I helped design and build as graduate student (and sometimes have to fix), is here. This is a picture of us putting the front window of the camera, which is also the last corrector plate of the survey telescope, into its cell (very carefully!) The colored glass squares are the filters, one for each CCD.
The ARC Echelle spectrograph, on the 3.5m telescope at Apache Point
Observatory, is described here.
Last year I rode shotgun, so to speak, with Steve Vogt on a design study for a high-resolution spectrograph for the Thirty Meter Telescope. Imagine an instrument that can dissect the spectrum of an astronomical object in fine enough detail to measure the abundances of elements like iron and magnesium, and all the way on down through exotic elements like europium and yttrium. Now imagine putting that spectrograph behind a telescope big enough to study stars out to the edge of the Galaxy. It would also be powerful enough to use the back-lighting from quasars to examine chemical abundances in interstellar and intergalactic gas at cosmological distances with the same quality data as for Galactic stars.
Before coming to Santa Cruz, I was a Hubble Postdoctoral Fellow
in the University of Washington, Seattle Astronomy Department
Apache Point Observatory, where the SDSS and SEGUE surveys happen.
Lick Observatory on Mt. Hamilton, where I hope to do some adaptive optics observations this coming semester.
W. M. Keck Observatory, where I have observed on the HIRES and ESI spectrographs.
The Thirty Meter Telescope, a future giant telescope project worked on by people at Santa Cruz and elsewhere.
Info on backcountry permits and conditions for the Inyo National Forest, in the Sierra Nevada mountains.
Check here to see if Tioga pass in Yosemite National Park is open.