Sarah was raised in Sioux Falls, South Dakota where she always had the dream of becoming an astronaut. She is currently working on her Astronomy degree and is a Math tutor at the University of Hawaii at Hilo. She will graduate next spring. After graduation she plans to work in the Astronomy field and finish her Math and Psychology degrees. Sarah is very excited to be interning with the CfAO.

Home Island: Big Island

Institution when acceptedUniversity of Hawaii at Hilo

Akamai Project: Effects of Temperature Variation on the Telescope Pointing at the Submillimeter Array

Project Site: Smithsonian Astrophysical Observatory/ASIAA

Mentor: Billie Chitwood

Project Abstract:

Temperature effects on the pointing of antennas at the Smithsonian Submillimeter Array (SMA) are important because observing can be done during the day, when there is the most temperature variation. Although temperature surveys have been done before, this project is more specific. The goal of this project was to analyze how temperature variation affects the pointing of Antenna 5 at the SMA. Although there are temperature sensors all over the antenna, we focused on the quadrapods, the reflector mount, and the base ring. The quadrapods are four legs that hold the secondary reflector in place, and the reflector mount holds the primary reflector in place. To investigate effects on the base ring – the center support of the entire antenna – I built a harness that holds temperature sensors and installed it on the base ring. I also edited a program in LabVIEW to read out the temperature output of the sensors. After installing the harness, data on temperature versus the pointing displacement was analyzed. The pointing displacement was measured using optical observations. I took snapshots of bright objects at sunset and then again after sunset, when the temperature stabilizes. The difference between the offsets of both pictures is the pointing displacement. There were significant temperature effects on the pointing of Antenna 5, up to a displacement of 0.3”.