Bennu’s near-Earth lifetime of 1.75 million years inferred from craters on its boulders

  title={Bennu’s near-Earth lifetime of 1.75 million years inferred from craters on its boulders},
  author={R.-L. Ballouz and Kevin John Walsh and Olivier S. Barnouin and Daniella N. DellaGiustina and Manar Al Asad and Erica R. Jawin and Michael G. Daly and William F. Bottke and Patrick Michel and Chrysa Avdellidou and Marco Delbo’ and R. T. Daly and Erik Asphaug and Carina A. Bennett and Edward B. Bierhaus and Harold C. Connolly and Dathon R. Golish and Jamie L. Molaro and Michael C. Nolan and Maurizio Pajola and Bashar Rizk and Stephen R. Schwartz and David Trang and Catherine W. V. Wolner and Dante S. Lauretta},
An asteroid’s history is determined in large part by its strength against collisions with other objects 1 , 2 (impact strength). Laboratory experiments on centimetre-scale meteorites 3 have been extrapolated and buttressed with numerical simulations to derive the impact strength at the asteroid scale 4 , 5 . In situ evidence of impacts on boulders on airless planetary bodies has come from Apollo lunar samples 6 and images of the asteroid (25143) Itokawa 7 . It has not yet been possible, however… Expand
16 Citations
High-resolution observations of bright boulders on asteroid Ryugu: 1. Size frequency distribution and morphology
Abstract The near-Earth asteroid (162173) Ryugu displays a Cb-type average spectrum and a very low average normal albedo of 0.04. Although the majority of boulders on Ryugu have reflectance spectraExpand
High-resolution observations of bright boulders on asteroid Ryugu: 2. Spectral properties
Abstract Many small boulders with reflectance values higher than 1.5 times the average reflectance have been found on the near-Earth asteroid 162,173 Ryugu. Based on their visible wavelength spectralExpand
Fine-regolith production on asteroids controlled by rock porosity.
It is interpreted to mean that accumulation of unconsolidated subcentimetre particles is frustrated where the rocks are highly porous, which appears to be most of the surface of Bennu, and that regolith blankets are uncommon on carbonaceous asteroids, which are the most numerous type of asteroid. Expand
Modified granular impact force laws for the OSIRIS-REx touchdown on the surface of asteroid (101955) Bennu
  • R. Ballouz, K J Walsh, +13 authors D. Lauretta
  • Physics
  • Monthly Notices of the Royal Astronomical Society
  • 2021
The OSIRIS-REx mission collected a sample from the surface of the asteroid (101955) Bennu in 2020 October. Here, we study the impact of the OSIRIS-REx Touch-and-Go Sampling Acquisition MechanismExpand
In search of Bennu analogs: Hapke modeling of meteorite mixtures
Context. The OSIRIS-REx Visible and InfraRed Spectrometer onboard the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer spacecraft obtained many spectra fromExpand
Diurnal temperature variation as the source of the preferential direction of fractures on asteroids: Theoretical model for the case of Bennu
Abstract It has been shown that temperature cycles on airless bodies of our Solar System can cause damaging of surface materials. Nevertheless, propagation mechanisms in the case of space objects areExpand
Tensile strength and elastic properties of fine-grained ice aggregates: Implications for crater formation on small icy bodies
Abstract The mechanical and elastic properties of ice aggregates (snow) are important in the physics of avalanches and crater formation on icy bodies, such as icy satellites and cometary nuclei. HereExpand
Particle Size-Frequency Distributions of the OSIRIS-REx Candidate Sample Sites on Asteroid (101955) Bennu
Higher-resolution data from regional observations were used to calculate particle size-frequency distributions (PSFDs) and assess the viability of four candidate sites for sample collection and found that each site has experienced different geologic processing. Expand
Bennu regolith mobilized by TAGSAM: Expectations for the OSIRIS-REx sample collection event and application to understanding naturally ejected particles
Abstract The Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer (OSIRIS-REx) mission will collect material from the asteroid Bennu and return it to Earth. TheExpand
Impacts on the Moon: Analysis methods and size distribution of impactors
Abstract We are preparing a telescope system to carry out a survey of detection and analysis of lunar impact flashes. In the framework of this project, here we present all necessary methods toExpand


Craters, boulders and regolith of (101955) Bennu indicative of an old and dynamic surface
Small, kilometre-sized near-Earth asteroids are expected to have young and frequently refreshed surfaces for two reasons: collisional disruptions are frequent in the main asteroid belt where theyExpand
The Geologically Recent Giant Impact Basins at Vesta’s South Pole
Dawn’s global mapping of Vesta reveals that its observed south polar depression is composed of two overlapping giant impact features, which provide exceptional windows into impact processes at planetary scales, and spacecraft data provide a detailed characterization of the second most massive asteroid in the solar system. Expand
Low thermal conductivity boulder with high porosity identified on C-type asteroid (162173) Ryugu
C-type asteroids are among the most pristine objects in the Solar System, but little is known about their interior structure and surface properties. Telescopic thermal infrared observations have soExpand
Thermal fatigue as the origin of regolith on small asteroids
It is reported that thermal fatigue, a mechanism of rock weathering and fragmentation with no subsequent ejection, is the dominant process governing regolith generation on small asteroids and that thermal fragmentation induced by the diurnal temperature variations breaks up rocks larger than a few centimetres more quickly than do micrometeoroid impacts. Expand
Impact process of boulders on the surface of asteroid 25143 Itokawa—fragments from collisional disruption
The subkilometer-size asteroid 25143 Itokawa is considered to have a gravitationally bounded rubble-pile structure. Boulders appearing in high-resolution images retrieved by the Hayabusa missionExpand
Cumulative Damage in Strength-Dominated Collisions of Rocky Asteroids: Rubble Piles and Brick Piles
Abstract Laboratory impact experiments were performed to investigate the conditions that produce large-scale damage in rock targets. Aluminum cylinders (6.3 mm diameter) impacted basalt cylinders (69Expand
Collisional balance of the meteoritic complex
Taking into account meteoroid measurements by in situ experiments, zodiacal light observations, and oblique angle hypervelocity impact studies, it is found that the observed size distributions ofExpand
The flux of small near-Earth objects colliding with the Earth
Satellite records of bolide detonations in the atmosphere over the past 8.5 years are reported and it is found that the flux of objects in the 1–10-m size range has the same power-law distribution as bodies with diameters >50 m. Expand
Impact cratering and break up of the small bodies of the Solar System
Abstract We consider the largest impact craters observed on small satellites and asteroids and the impact disruption of such bodies. Observational data are considered from 21 impact-like structuresExpand
Catastrophic rupture of lunar rocks: A Monte Carlo simulation
A computer model based on Monte Carlo techniques was developed to simulate the destruction of lunar rocks by ‘catastrophic rupture’ due to meteoroid impact. Energies necessary to accomplishExpand