The Student Nitric Oxide Explorer (SNOE or "snowy") is a small scientific satellite that measured the effects of energy from the sun and from the magnetosphere on the density of nitric oxide in the Earth's upper atmosphere. The spacecraft and its instruments were designed and built at LASP, the Laboratory for Atmospheric and Space Physics of the University of Colorado. SNOE was launched by a Pegasus XL into a circular orbit, 580 km altitude, at 97.75 degrees inclination for sun synchronous precession on February 27, 1998 and re-entered the atmosphere on December 13, 2003.
It carried three instruments: an ultraviolet spectrometer to measure nitric oxide altitude profiles, a two-channel auroral photometer to measure auroral emissions beneath the spacecraft, and a five-channel solar soft X-ray photometer.