Cerro Tololo

We watched the sunset tonight from atop Cerro Tololo, and then ran inside to the telescope control room to begin our work. This is my second night observing with our REU coordinator Stella, and a fellow REU student Matt. Cerro Tololo is a 90 minute drive from La Serena, along winding dirt roads, and ascending to about 7,000 feet altitude.

During our first day here, we moved into our house, and took a look around the cerro (hill). There are a bunch of telescopes on Cerros Tololo and Pachon: Blanco 4 m, SOAR 4.1 m, and smaller telescopes. We're working on the Yale 1 meter telescope; this measurement indicates the diameter of the mirror. Each day before observing, we check the telescope to make sure it is aligned, and the room is clear. The telescope is huge, with so many instrumental components!! In the evening, the dome is opened so the telescope can see out, and we take what are called "flats", used to calibrate the data that we take at night.

We work the most when the sun goes down, and the stars become visible. Here, we don't want the sun, moon, or clouds to get in the way, so a clear sunset is the most beautiful kind!! During our REU observing run, we've had 8 clear nights, and we've taken turns in pairs during two-night shifts to measure the data. We've had what is called "good seeing."

Last night, I was in charge of tracking and telescope focus. Tonight, I'm sitting at the observer's console. I think that astronomers could do this stuff remotely, but they like to work together, and be near their precious telescope during the night. During this run, we're doing photometry, which means we're taking very detailed pictures of the sky. Basically, we type in coordinates to direct the telescope to a certain point in the sky (we can feel the room rumble as the telescope moves in the room above us!), then we tell the telescope camera the exposure time and the filter to use.

We're observing for Stella's collaborations, and we have a strict schedule tonight to take five different filters at ten different exposure times for some standard stars and a star cluster throughout the night. Our schedule began at 9:45 pm, and we'll take our last sky flats at 6:15 am, just before the sun begins to peak over the mountains and light the sky.

The best part of the job is when we take a long exposure, we have time to head outside into the blackness of the night, look up, and view this cluster and so much more, as we become acquainted with the southern sky.

To see pictures, go to my photo log, http://picasaweb.google.com/plunkettadele/CerroTololo