A Summer at the Arecibo Observatory

Clarissa Leight '18

Clarissa Leight '18

Major: Astronomy

Internship: MHC Astronomy Department, Research Assistant

I spent my summer in the REU program at the Arecibo Telescope, working with staff scientist Dr. Edgar Rivera-Valentin. I studied the cratering history of Rhea and Dione, looking to constrain the planetesimal disk mass from their cratering rates. To do this, I learned about the Nice model of solar system evolution, and Saturn's moons Rhea and Dione.

The Nice model explains how the planets reached their current positions, the Late Heavy Bombardment, and predicts a total bombardment mass for all of the bodies in the solar system, which we called Mnice. By comparing theoretical simulations to the observed cratering record, we can constrain the total bombardment mass, and thus the planetesimal disk mass. I ran IDL codes to model impacts on the bodies, running through 16 total bombardment masses ranging from .001 to 2 times Mnice. The code asked the computer to keep track of how many impacts occurred at any location on the body, the melt production of the impacts, the velocity, and total impact mass for 100 simulations of the 16 masses. We then ran a statistical analysis of the simulations, and compared it to the crater counts of Rhea and Dione, collected previously by Kirchoff. It was a lot of troubleshooting code, error messages, and being confused, which ultimately paid off.

Through the REU colloquia talks I learned about the history of Arecibo, galactic H1, the ionosphere, LIDAR, what makes a galaxy a galaxy, the optics of the telescope, and so much more. The staff scientists at Arecibo were all super into their research and more than happy to have the students hanging around and asking questions.

During the weekends we, the REU students, bonded and took trips around the island. We took a Tanama river tour, went to the Puerto Rican Arts festival, and visited Old San Juan. Robert, one of the REU mentors, took us to see the Puerto Rican Parrots in a nearby reserve.

My internship ended with me attending the 2016 Division of Planetary Science conference in Pasadena CA, where I presented my findings on Rhea's bombardment mass. My time at Arecibo Observatory was amazing, and I’m super grateful for the research experience and friends I gained this summer!