DESIGNING A FAR ULTRAVIOLET SPECTROMETER FOR THE SUN AS A STAR

Charles Kankelborg
Department of Physics
Montana State University

 

Abstract

The Full-sun Ultraviolet Rocket Spectrograph (FURST) will obtain the first high resolution spectra of the Sun as a star in far ultraviolet. It is an instrument that could only be built in the space age. Design challenges included taking an unbiased sample of the spectrum of an extended object, obtaining high spectral resolution and high signal-to-noise ratio in a 5 minute measurement, resolving spectral line profiles, minimizing scattered light, and achieving absolute radiometric and wavelength calibration. Beginning from classic spectrometer designs developed more than a century ago, I will describe the thought process behind the FURST design.

Biographical Sketch

A native of Tacoma, Washington, Charles Kankelborg was the first in his family to graduate from college, earning a B.S. in Physics from the University of Puget Sound in 1989. In graduate school at Stanford University, he worked in Prof. Arthur Walker's research group, using a rocket payload to form images of the Sun in extreme ultraviolet. After completing his PhD in in 1996, he moved to Bozeman as a postdoctoral researcher working on the NASA Transition Region and Coronal Explorer (TRACE) under the mentorship of Loren Acton. In 2001, he joined the MSU faculty. He has launched three successful NASA sounding rocket missions as a principal investigator, including the Extreme Ultraviolet Snapshot Imaging Spectrograph (ESIS) in 2019. His new rocket mission, FURST, will investigate the ultraviolet spectrum of the Sun as a star. Charles is a co-investigator on the NASA IRIS satellite mission which launched in June of 2013; Hi-C Flare, a sounding rocket investigation of solar flares; and MUSE, a prospective NASA Medium-class Explorer mission.