In the latest segment of our ongoing series Born at UC Berkeley, Angela Zhang (class of '26) suits up to learn about Berkeley's newest satellite: the Compton Spectrometer and Imager (COSI). Funded by NASA, it is one of a long string of satellites and space missions designed, built and operated at the campus's Space Sciences Laboratory. Scientists at the lab must wear bunny suits to prevent dust from getting into the sensitive optical system of the satellite, which should launch into Earth orbit next year.
The COSI mission, led by John Tomsick, SSL associate director for astrophysics and exoplanets, is designed to scan the skies for gamma rays - very energetic photons of light emitted in the aftermath of supernovas as the elements created in the explosion decay. But gamma rays are also created when electrons encounter their antimatter counterpart, a positron, and annihilate into pure energy.
By mapping gamma rays in the Milky Way Galaxy, Tomsick and his team hope to understand why there are more positrons around than people thought, and answer questions about the origin of the chemical elements in our galaxy - elements critical to the formation of Earth.
As with most SSL missions, undergraduates and graduate students play a big role in building and testing the instruments. Through internships and fellowships, SSL is training a new generation of space scientists and engineers poised to make the next great cosmic discoveries.
