2014.B.2.5 CubeSat technology adaptation for in-situ characterization of NEOs

Author(s)

Steven Koontz (1)
Riccardo Bevilacqua (2)

NASA JSC, USA
Rensselaer Polytechnic Institute, USA

Session

B.2

Keywords

NEO rendezvous in-situ

Abstract

We report a preliminary spacecraft and mission design study that demonstrates proof of concept for microsatellite missions to Near Earth Objects (NEOs). The microsatellite is designed to address the need for in-situ measurements of surface and bulk properties of the NEO population needed to support future mission planning and engineering design. The design study describes a small, low-cost autonomous NASA class D reconnaissance spacecraft constructed of primarily Commercial Off-The-Shelf (COTS) components and designed around a NEO rendezvous mission concept that minimizes mission flight time and mission costs. The spacecraft will be referred to as the NEO-Scout Proof of Concept (NEO-SPOC).

The bulk NEO population has not yet been characterized with high certainty. For most NEOs, factors of 2 to 10 uncertainty in simply physical size are typical. Telescopic data implies that these NEOs are highly diverse in nature. By analyzing these NEOs, important resources such as water and rare-earth elements could be discovered that may assist in the next step in human exploration. The NEO-SPOC’s plug-and-play capabilities enable an adaptive payload able to carry various sensors, depending on mission objectives. These sensors can be used to measure properties such as physical size, density, spin rate, albedo, surface properties, and surface composition.

The NEO-SPOC is constructed around a linear 4U CubeSat chassis. By utilizing commercially available CubeSat modules, the base design can be replicated for a multitude of NEO targets. Furthermore, each of these modules are COTS parts in effort to reduce cost and utilize past flight heritage. By rendezvousing with NEOs prior to close approach (< 0.15 AU) to the Earth-Moon system, mission duration can be reduced to less than 400 days, while simultaneously reducing telemetry burden, mission success risk, and mission operations costs compared to more traditional multi-year interplanetary missions. These microsatellites will be launched as secondary payloads aboard launch vehicles headed to GTO or beyond. With a target maximum wet mass of less than 15 kg, the NEO-SPOC utilizes a Hall Effect thruster with solid iodine as fuel. This enables rendezvous with a wide range of NEOs that pass close to the Earth moon system using less than 5 kg of fuel and less than 400 days of mission operation time.