NEOShare: A Smallsat Mission to Explore the Diversity of Near-Earth Asteroids

Presently, > 20,000 near-Earth objects (NEOs) have known orbital characteristics. About 10% are characterized as Potentially Hazardous Objects (PHOs) that approach within about 20 Earth-Moon distances. Some of these NEOs have undergone additional characterization (e.g.,colors, spectra), a small number have had their shapes and other properties determined by Goldstone and Arecibo radar, and five have been visited by robotic missions (Eros, Itokawa, Toutatis, Ryugu, Bennu). Given the broad range of known sizes and colors/spectra (and thus compositions) as well as inferred densities, porosities, binarity, family membership, and hazard potential, there is clearly a need for additional up-close study of the diversity of this population. Indeed, the need to more fully characterize this diversity was part of the justification for listing NEO missions as of high interest in the currently-active NASA Planetary Decadal Survey.

To that end, the MILO Space Science Institute, a non-profit deep space mission collaboration between Arizona State University, Lockheed Martin, and GEOShare, is planning a mission called NEOShare. This mission would launch (in 2023) a cluster of six smallsats that would each perform a close flyby of a different NEO relatively close to Earth. Each smallsat would be equipped with cameras, spectrometers, and potentially other high-heritage instrumentation. Because some of the smallsats can be directed to flyby multiple objects, we plan to characterize at least eight new NEOs during the mission. NEOShare will be conducted by a consortium of U.S. and international universities and space agencies that join the MILO Institute`s membership-based model for deep space exploration.