Rebecca Holmes, Los Alamos National Laboratory; Charles Weaver, Los Alamos National Laboratory; David Palmer, Los Alamos National Laboratory
Keywords: Space object identification, optical, space debris, cubesat, single-photon detector
Abstract:
The Extremely Low Resource Optical Identifier (ELROI) beacon is a milliwatt optical license plate that can provide unique ID numbers for everything that goes into space. ELROI is designed to help address the problem of space object identification (SOI) in the crowded space around the Earth, where over 16,000 objectsfrom active satellites to rocket bodies and debrisare tracked and monitored today. Tracking these objects is an essential part of the United States multi-billion-dollar SSA effort, and requires continuous knowledge of each objects position and trajectory. Re-identifying a lost object is significantly easier if it carries a beacon that can be read from the ground. There is currently no standard beacon technology that is small and light enough for the smallest satellites, and radio beacons have the additional drawback of RF interference.
ELROI is a new concept for an autonomous optical beacon that uses short, omnidirectional flashes of laser light to encode a unique ID number. ELROI is smaller and lighter than a typical radio beacon, is powered by its own small solar cell, and can safely operate for the entire orbital lifetime of the host object without producing interference. Using photon counting to enable extreme background rejection in real time, the ID number can be uniquely identified from the ground in a few minutes, even if the ground station detects only a few photons per second. The ELROI IDs are open and designed to be readable by anyone with a suitable ground station, which requires a small telescope and a single-photon sensor.
Simplifying SOI for known objects frees up SSA resources for identifying new objects and possible threats. Small satellites such as CubeSats are also being deployed in increasingly larger groups, and it is difficult for a typical CubeSat operator to identify their own satellite in the crowd without a beaconparticularly important when there is an anomaly. An optical beacon also has the potential to be a black box for satellites, transmitting low-bandwidth emergency telemetry information if the host satellite is disabled. The ELROI concept has been validated in long-range ground tests, and orbital prototypes are scheduled for launch in 2018/2019. We will discuss the development and applications of this new SOI technology, and any results from the test flight scheduled this year.
Date of Conference: September 11-14, 2018
Track: Poster