Shane Ryall, Defence Research Development Canada; Stefan Thorsteinson, Defence Research Development Canada
Keywords: SSA, SDA
Abstract:
This paper summarizes results from a two-year campaign of repeated imaging of the Canadian Satellite Tracking List (CSTL): a collection of Canadian-attributed resident space objects, and investigates an experiment into the feasibility of maintaining long term custody of many objects with a single space-based sensor. The Near-Earth Orbit Surveillance Satellite (NEOSSat) is a research micro-satellite space telescope, performing Space Domain Awareness (SDA) experimentation for Defence Research and Development Canada. Beginning in fall 2020, CSTL objects were tracked consistently by NEOSSat with re-visit periods varying from daily to several weeks. The CSTL contains both inactive and active Canadian space objects, of which 27 are at or near Geosynchronous (GEO) orbit and 4 in Low Earth Orbit (LEO) satisfying NEOSSats visibility and tracking capabilities.
This paper focuses on the exploitation of metric observations of both well and infrequently tracked objects. Photometric results from NEOSSats optical observations were employed to refine tasking opportunities on difficult to track objects. CSTL object orbit determination results from repeated measurements are presented on well sampled functioning and derelict GEO objects and on infrequently spaced LEO to LEO measurements. As a space-based sensor NEOSSat relies on ground station contact for uplink of taskings and then downlink of imagery leading to multi-day delays between tasking requests and observation creation. Given NEOSSats narrow 0.85 degree field of view, tasking requests require decent a-priori orbital estimates. A summary of results maintaining orbit custody and re-imaging CSTL objects long term is presented, using single sensor derived element sets.
In the final phase, batch least squares orbit estimation was employed to generate orbits from 2023 observations, and NEOSSat was tasked using these updated orbits to evaluate the accuracy of our orbit determination methods and the overall pipeline. This process was repeated twice following the initial observation. Ultimately, 20 out of 27 satellites were successfully re-observed on the second revisit with in-house orbits. The success of this experiment demonstrates that a single sensor is capable of maintaining long-term custody of Canadian objects, and that with the current state of Canadian-owned objects in space, a national catalogue is well within reach of its operational community.
Date of Conference: September 19-22, 2023
Track: Space Domain Awareness