Instrument: Echellette Spectrograph and Imager
Telescope: Keck II
Wavelength: visible light
Instrument Scientist: Dr. Jim Lyke
Principal Investigator: Joe Miller, UCO/Lick Observatory
Description: Optical instrument that captures spectra of faint galaxies and quasars from the blue to red spectrum in a single exposure. ESI is typically used for taking spectra of one, specific object at a given time, allowing observers to study it with superior detail.
Unique Feature: Great wavelength coverage at fine spectra resolution.
Research: It is used to study white dwarfs, or dead stars, polluted with heavy elements from rocky bodies like planets, asteroids, and comets that once orbited the star before its death. Studying the chemical composition of these pollutants helps inform models describing the formation and evolution of exoplanets.
Notable Contributions: Some of ESI’s early results were critical to learning about galaxies early on in the universe, and they drove the effort for newer, better instruments that could help uncover the questions ESI’s results prompted.

“I appreciate ESI for its incredible stability, which allows astronomers to compare results from a timespan of several years.” ~ Dr. Jim Lyke