Title: The RAVAN CubeSat Mission: On-Orbit Demonstration
Presenting Author: William Swartz
Organization: JHU/Applied Physics Laboratory
Co-Author(s): Steven R. Lorentz, Philip M. Huang, Allan W. Smith, James Briscoe, Edward L. Reynolds, John Carvo, Dong Wu

Abstract:
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) 3U CubeSat mission is a NASA Earth Science Technology Office-funded pathfinder for a future constellation to measure the Earth’s energy imbalance–the single most important quantity for predicting the course of climate change over the next century. RAVAN launched November 11, 2016 into a nearly 600-km sun-synchronous orbit. RAVAN demonstrates two key technologies. First, we show measurements of Earth’s outgoing energy with radiometers that use vertically aligned carbon nanotube (VACNT) absorbers. VACNT forests are some of the blackest materials known and have an extremely flat spectral response over a wide wavelength range. The measurements are made at both shortwave, solar-reflected wavelengths and in the thermal infrared. Second, we show the performance of two gallium phase-change cells that are used to monitor the degradation of RAVAN’s radiometer sensors. A 3-axis controlled CubeSat bus allows for routine solar and deep-space attitude maneuvers, which are essential for calibrating Earth irradiance measurements. In addition to Earth energy budget technology and science, RAVAN also demonstrates partnering with a commercial vendor for the CubeSat bus, payload integration and test, and mission operations. We will share lessons learned from this approach. RAVAN will help enable the development of an Earth energy imbalance constellation mission that can provide the measurements needed for superior predictions of future climate change.