Student researcher: Julian Kop, Mentors: Katrina Hay, Sean O'Neill There are two possible physical causes for periodic variations in observed star brightness. The first is that the stars develop physical pulsations that modulate the amount of light emitted from their surfaces. The other possibility is that light from a star is regularly obscured by an orbiting companion (such as another star), which allows astronomers to determine the companion object’s mass. Julian is using a charge-coupled device (CCD) camera attached to our 16-inch telescope, to calibrate estimates of the brightness minima/maxima. He will process data using professional astronomy photometry techniques. The fundamental goal of this project is to connect what is seen through the telescope with the physics that must be happening at the source.
Student researcher: Jessica Ordaz, Mentors: Katrina Hay, Sean O'Neill Globular clusters are some of the oldest objects in our galaxy. They are clusters of densely packed stars, gravitationally bound into a relatively compact spherical shape. While they are rare, astronomically speaking, there are approximately 200 of these clusters in our galaxy, and many of them are visible and bright enough (some even with the naked eye) to be photographed through a telescope with a CCD camera. Each cluster contains stars that are roughly the same age, formed at the same time, interestingly followed by no further star formation. This feature makes them like star time-capsules, or fossils of the early universe, containing information about the ancient universe. We can estimate the age of these clusters, and, by extension, discover clues about our galaxy and universe, by studying the stars in these clusters. Jessica is studying stellar evolution and classification and will measure the luminosity (brightness), color (temperature), and density distribution of the stars in the globular clusters to estimate the ages of these clusters.
Summer 2018 Research
Student researcher: Justin deMattos, Mentors: Katrina Hay, Sean O'Neill Saturn's rings are composed of particles of ice and dust that are thought to be remnants of comets, asteroids, or moons that collided in orbit around the planet. Since these rings are not single structures, their particles feature non-uniform spacing. The intensity of the rings increases as you approach the B ring from either direction (with the exceptions of the Cassini Division, Encke, and Keeler gaps). Our research focused on determining the rate at which these intensities increase and decrease to estimate how the ring density varies throughout the ring system.
Student researcher: Megan Longstaff, Mentors: Katrina Hay, Sean O'Neill Jupiter's atmosphere is subject to differential rotation in which the bands and zones of the planet rotate at different speeds. The Great Red Spot (GRS) is located 22 degrees south of Jupiter's equator and has a drift velocity which changes its rotational period monthly. We use feature tracking and 2D to 3D mapping techniques to observationally determine the rotation of the GRS and compare it to the expected rotation rate of 11.5 km/s determined by observations of the magnetosphere. Through our analysis we observe the movement of the GRS over multiple nights and construct an average speed based on this data. We determine the average speed of the GRS to be around 10.97 km/s, a 4.60% difference from the expected value.
Summer 2016 Research
Student researcher: Kimberly Belmes, Mentors: Katrina Hay, Sean O’Neill In the summer of 2016, we investigated the relationship between area and decay rate for sunspots within the range of 35–1000 μHem (one μHem = one millionth of one solar disk area) in area, as well as the relationship between decay rate and latitude. We analyzed these correlations via data from NASA’s Solar and Heliospheric Observatory (SOHO). We also analyzed the temperature ratio of sunspots’ umbra to the solar photosphere using data collected from Pacific Lutheran University’s W.M. Keck Observatory. Our results indicate linear correlations between growth rate and area as well as decay rate and area, and we find neither a significant correlation between latitude and growth rate nor latitude and decay rate. We obtained accurate sunspot-to-photosphere temperature ratios.
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