Aishling Dignam, NSF NOIRLab
Keywords: space situational awareness, astronomy, telescope, observations
Abstract:
Rapid growth in commercial space activity has brought space sustainability to the forefront of Space Situational Awareness (SSA) and Space Domain Awareness (SDA). Currently, the safety and sustainability of operations in the near-Earth environment require consideration in this ever more crowded space. In addition to satellite operations, astronomical observatories are facing the challenge of minimizing the impact of the increase in satellite numbers on their operations and services. Optical and radio facilities are particularly affected in dealing with the interference this poses to astronomical data. However, this contamination in optical observations, while troublesome for astronomy, can be used as a source of high-quality satellite observations, expanding the current data sources used in SSA observations.
NOIRLab is a facility which is a partner in and runs many of the large telescopes in the world, including the Gemini Observatory, Cerro Tololo and, soon, the Vera C. Rubin Observatory. These optical telescopes encounter the bright signatures of satellites within observations, especially satellites in Low Earth Orbit. This can leave a bright streak in the image, much brighter than any other light source and can have the potential to damage sensors. To navigate this, the affected images may be disregarded or the satellite is removed in post-processing, a procedure which may lead to a loss of data. As part of ongoing work at NOIRLab, we are exploring methods to exploit these opportunistic observations of satellites with astronomical observatories which are equipped with instruments that are not routinely employed in SSA observations.
Using this unconventional astronomical data, we investigate the capabilities of these observatories to observe, identify and characterize satellites. As with many observatories, NOIRLab possesses databases of legacy observations from the various telescopes. Combining these legacy data with contemporary observations shows potential for expanding upon the data sources we can use to observe satellites and their properties, such as position, brightness and materials.
This analysis presents the capabilities and drawbacks of using astronomical observatories and observations to complement current SSA observation methods. Varied instrumentation is utilized in this investigation as many data are acquired through unintentional observation and the instrument used is the one chosen for a specific astronomical observation. These are examined for their current and future utility for satellite characterization.
From this assessment, we can better understand the impact of satellite interference on optical observatories. The potential present in using these publicly available data to further characterize satellites is discussed to ascertain the advantages of various instrumentation and telescopes. Improved insight on this issue can aid in creating equitable methods for satellite operators and astronomers to minimize satellite interference in imaging.
Date of Conference: September 16-19, 2025
Track: Space Domain Awareness