Constraining the Physical Properties of Near-Earth Object 2009 BD

Abstract

We report on Spitzer Space Telescope IRAC observations of near-Earth object (NEO) 2009 BD that were carried out in support of the NASA Asteroid Robotic Retrieval Mission (ARRM) concept. We did not detect 2009 BD in 25 hrs of integration at 4.5 micron. Based on an upper-limit flux density determination from our data, we present a probabilistic derivation of the physical properties of this object. The analysis is based on the combination of a thermophysical model with an orbital model accounting for the non-gravitational forces acting upon the body. We find two physically possible solutions. The first solution shows 2009 BD as a 2.9+/-0.3 m diameter rocky body (rho = 2.9+/-0.5 g cm-3) with an extremely high albedo of 0.85(+0.20/-0.10) that is covered with regolith-like material, causing it to exhibit a low thermal inertia (Gamma = 30(+20/-10) SI units). The second solution suggests 2009 BD to be a 4+/-1 m diameter asteroid with pV = 0.45(+0.35/-0.15) that consists of a collection of individual bare rock slabs (Gamma = 2000+/-1000 SI units, rho = 1.7(+0.7/-0.4) g cm-3). We are unable to rule out either solution based on physical reasoning. 2009 BD is the smallest asteroid for which physical properties have been constrained, in this case using an indirect method and based on a detection limit, providing unique information on the physical properties of objects in the size range smaller than 10 m.

arXiv comment28 pages, 8 figures, accepted for publication in ApJ

References in corpus (20)

• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• The Infrared Array Camera (IRAC) for the Spitzer Space Telescope
• The Spitzer Space Telescope Mission
• NEOWISE Observations of Near-Earth Objects: Preliminary Results
• Scaling forces to asteroid surfaces: The role of cohesion
• Thermal inertia of near-Earth asteroids and implications for the magnitude of the Yarkovsky effect
• Near Earth Asteroids with measurable Yarkovsky effect
• Thermo-physical properties of 162173 (1999 JU3), a potential flyby and rendezvous target for interplanetary missions
• Eclipsing Binary Trojan Asteroid Patroclus: Thermal Inertia from Spitzer Observations
• Main Belt Binary Asteroidal Systems With Eccentric Mutual Orbits
• The Population of Tiny Near-Earth Objects Observed by NEOWISE
• Surface composition and taxonomic classification of a group of near-Earth and Mars-crossing asteroids
• Physical Properties of OSIRIS-REx Target Asteroid (101955) 1999 RQ36 derived from Herschel, ESO-VISIR and Spitzer observations
• Thermophysical properties of near-Earth asteroid (341843) 2008 EV5 from WISE data
• Assessment of the 2880 impact threat from asteroid (29075) 1950 DA
• A thermophysical analysis of the (1862) Apollo Yarkovsky and YORP effects
• Thermal infrared observations of near-Earth asteroid 2002 NY40
• Detection of radiation pressure acting on 2009 BD
• Physical Properties of Asteroid (308635) 2005 YU55 derived from multi-instrument infrared observations during a very close Earth-Approach
• Characterization of the near-Earth Asteroid 2002NY40

Cited by in corpus (22)

• Spitzer Observations of Interstellar Object 1I/`Oumuamua
• Orbital and Physical Characteristics of Meter-scale Impactors from Airburst Observations
• Observation of metre-scale impactors by the Desert Fireball Network
• Yarkovsky Drift Detections for 247 Near-Earth Asteroids
• Detecting the Yarkovsky effect among near-Earth asteroids from astrometric data
• Physical Properties of Near-Earth Asteroid 2011 MD
• Establishing Earth's Minimoon Population through Characterization of Asteroid 2020 CD${}_3$
• Low thermal conductivity of the superfast rotator (499998) 2011 PT
• The size-frequency distribution of H>13 NEOs and ARM targets detected by Pan-STARRS1
• The atmospheric impact trajectory of asteroid 2014 AA
• The size distribution of Near Earth Objects larger than 10 meters
• Meteoroid impacts onto asteroids: a competitor for Yarkovsky and YORP
• NEOSurvey 1: Initial results from the Warm Spitzer Exploration Science Survey of Near Earth Object Properties
• Non-gravitational Perturbations and Virtual Impactors: the case of asteroid 2009 FD
• An Investigation of the Ranges of Validity of Asteroid Thermal Models for Near-Earth Asteroid Observations
• Two Distinct Populations of Dark Comets Delineated by Orbits and Sizes
• Decameter-sized Earth impactors -- I: Orbital properties
• Spin Change of Asteroid 2012 TC4 probably by Radiation Torques
• Observing Near-Earth Objects with the James Webb Space Telescope
• The random walk of cars and their collision probabilities with planets
• Infrared Lightcurves of Near Earth Objects
• The Science Case for an Extended Spitzer Mission