Ground-Based NEA Characterisation and Planetary Defense Support from the South African Astronomical Observatory

The South African Astronomical Observatory (SAAO) continues to contribute meaningfully to global planetary defense efforts through the observation and characterisation of near-Earth asteroids (NEAs). Located in close to the town of Sutherland, the SAAO's site hosts a range of telescopes (1–10 m class) equipped with spectroscopy, photometry, and polarimetry capabilities. The robotic 1.0-m Lesedi telescope enhances rapid-response capabilities, enabling same-night follow-up of newly discovered NEAs.

SAAO has participated in multiple international campaigns coordinated by the International Asteroid Warning Network (IAWN), including the “2012 TC” (Reddy et al. 2019), “Apophis” (Reddy et al. 2022), and “2023 DZ2” (Reddy et al. 2024) exercises. SAAO facilities also contributed to ground-based monitoring of NASA’s DART mission impact with Dimorphos (Fitzsimmons et al., in review.), supporting the first successful asteroid deflection experiment.

With one of the southern nodes of the Asteroid Terrestrial-impact Last Alert System (ATLAS; Tonry et al. 2018) operational at SAAO, and the ongoing development of its “Intelligent Observatory” (IO) initiative (Potter et al. 2024), the observatory is well positioned to support the rapidly evolving landscape of planetary defense. These developments are timely as ESA’s NEOMIR mission, NASA’s NEOSurveyor, and the Vera C. Rubin Observatory promise to greatly increase NEA discoveries and follow-up demand.

This contribution outlines SAAO’s NEA-focused observing infrastructure and highlights selected contributions to recent planetary defense activities. It also discusses future plans to leverage underused facilities and further integrate SAAO’s capabilities into international response strategies.