Brian Banks, Leidos; Robert Smith II, Leidos; Ronald Wagner, Leidos; Victor Aguero, SRI International; Scott Williams, SRI International; Matthew Duncan, SpaceNav; Stijn De Smet, SpaceNav; Marc Balducci, SpaceNav
Keywords: Cislunar SSA, Astrodynamics, Imaging, Sensors, Optical Systems, Wide Field of View Optical Systems, Space-based Assets, Space Domain Awareness, Space Situation Awareness, Lunar Exploration, Lunar Mapping, Lunar Lander, Ground Penetrating Radar
Abstract:
This paper describes a sensor-rich solution to explore, map, and characterize the lunar/cislunar domain to support future human journeys to the moon, other moon exploration activities, and Space Domain Awareness. The solution addresses lunar orbital, surface, and subsurface domains.
The solution is designed to provide:
Detailed mapping of the lunar surface and the top layers below the surface
Lunar resource identification
Natural shelter identification on or below the lunar surface
Remote and proximity sensing and situational awareness of the lunar surface and cislunar orbital domain
Navigation support for vehicles on the lunar surface and cislunar orbital domain
Development of a shared cislunar navigation infrastructure by consolidating Positioning, Navigation and Timing (PNT) solutions into a distributed positional awareness array
Local and backhaul communications support for lunar surface and cislunar orbital domain
The paper covers the following topics:
Unattended Ground Sensors: Robust and hardened sensors dropped through the relatively low gravity of the moon onto the relatively soft surface of the moon. These unattended sensors self-initialize, self-organize, and provide various types of services (sensing, communications, position, navigation, timing). They provide precise ranging and spatial positioning data to lunar landers. (TRL=7)
Spacecraft to Deliver the Ground Sensors: These vehicles drop the ground sensors to strategic surface locations on the lunar surface from low lunar orbit. A Lunar Lander will also be described. (TRL=5)
Ground Penetrating Radar: A software-defined radar for profiling surface and sub-surface features of the moon and differentiating among various in situ resource utilization requirements such as deposits or surface characteristics (e.g., potential water/ice deposits). (TRL=6)
Multi-Spectral Telescope: Provides 6 bands in visible and 4 bands in MWIR range for detailed characterization of the lunar surface and resource content. (TRL=8)
Wide-Field-of-View Sensor: Provides wide-field-of-view imagery for navigation, situational awareness, and tracking. (TRL=8)
Precision Navigation Software without Need for Continuous Earth Ground Station Contacts: Utilizes the asymmetric gravity field in cislunar space to solve for the absolute state of the ESPA host and additional lunar/cislunar objects using relative ranging observations. That is, without earth ground station support, it can determine where the ESPA host is, as well as anything else around it providing robust Space Domain Awareness. This can provide navigation support and enhancement for approaching and operating crewed lunar missions, as well as lunar surface operations such as a rover. (TRL=3-4)
Mission goals addressed by this concept include superior awareness of the orbital and surface domain and natural shelter and resource identification. To satisfy these requirements, a versatile sensor suite is assembled combining ground-penetrating radar and electro-optical sensors. Given the limitations of size, weight, and power (SWaP) and budget typical for space exploration, each sensor is chosen for its multi-purpose, multi-mode capability in supporting various aspects of the mission.
The solution is based on exploiting high technology readiness level (TRL) sensors that are at least at TRL 6, i.e. have demonstrated performance and applicability to the lunar/cislunar domain exploration. Some of the sensors have gone through the full development cycle and acceptance tests achieving TRL 8 and some are in advanced stages of development and being tested and demonstrated at TRL 6 and 7.
Communications with other space assets are established to exchange data as well as to provide navigation and other assistance to other space assets. Data is selectively transmitted to earth for additional data processing, data fusion, and archival.
Date of Conference: September 15-18, 2020
Track: Cislunar SSA