Comparing NEO Search Telescopes

Abstract

Multiple terrestrial and space-based telescopes have been proposed for detecting and tracking near-Earth objects (NEOs). Detailed simulations of the search performance of these systems have used complex computer codes that are not widely available, which hinders accurate cross-comparison of the proposals and obscures whether they have consistent assumptions. Moreover, some proposed instruments would survey infrared (IR) bands, whereas others would operate in the visible band, and differences among asteroid thermal and visible light models used in the simulations further complicate like-to-like comparisons. I use simple physical principles to estimate basic performance metrics for the ground-based Large Synoptic Survey Telescope and three space-based instruments - Sentinel, NEOCam, and a Cubesat constellation. The performance is measured against two different NEO distributions, the Bottke et al. distribution of general NEOs, and the Veres et al. distribution of Earth impacting NEO. The results of the comparison show simplified relative performance metrics, including the expected number of NEOs visible in the search volumes and the initial detection rates expected for each system. Although these simplified comparisons do not capture all of the details, they give considerable insight into the physical factors limiting performance. Multiple asteroid thermal models are considered, including FRM, NEATM, and a new generalized form of FRM (GFRM). I describe issues with how IR albedo and emissivity have been estimated in previous studies, which may render them inaccurate. A thermal model for tumbling asteroids is also developed and suggests that tumbling asteroids may be surprisingly difficult for IR telescopes to observe.

References in corpus (15)

• Initial Performance of the NEOWISE Reactivation Mission
• Thermal inertia of main belt asteroids smaller than 100 km from IRAS data
• Main Belt Asteroids with WISE/NEOWISE: Near-Infrared Albedos
• The Dancing Sky: 6 years of night sky observations at Cerro Paranal
• Thermophysical modeling of asteroids from WISE thermal infrared data - Significance of the shape model and the pole orientation uncertainties
• Efficient intra- and inter-night linking of asteroid detections using kd-trees
• Asteroid Models from Multiple Data Sources
• Survey Simulations of a New Near-Earth Asteroid Detection System
• Dynamics of cloud features on Uranus
• Physical characterisation of near-Earth asteroid (1620) Geographos. Reconciling radar and thermal-infrared observations
• Optical Sky Brightness at Cerro Tololo Inter-American Observatory from 1992 to 2006
• Surface Properties of Asteroids from Mid-Infrared Observations and Thermophysical Modeling
• Asteroid rotation excitation by subcatastrophic impacts
• LSST: Comprehensive NEO Detection, Characterization, and Orbits
• A constellation of CubeSats with synthetic tracking cameras to search for 90% of potentially hazardous near-Earth objects

Cited by in corpus (7)

• Spitzer Observations of Interstellar Object 1I/`Oumuamua
• Modeling the Performance of the LSST in Surveying the Near-Earth Object Population
• Asteroid thermal modeling in the presence of reflected sunlight with an application to WISE/NEOWISE observational data
• Thermophysical Modeling of Asteroid Surfaces using Ellipsoid Shape Models
• A Deep and Wide Twilight Survey for Asteroids Interior to Earth and Venus
• Thermal radiation pressure as a possible mechanism for losing small particles on asteroids
• Thermal Modeling of Comet-Like Objects from AKARI Observation