A5027142599- Astro and Planetary Science
- Planetary Science and Exploration
- Space Satellite Systems and Control
- High-pressure geophysics and materials
- Fluid Dynamics Simulations and Interactions
- Nuts composition and effects
- Pulsars and Gravitational Waves Research
- Stellar, planetary, and galactic studies
- Linguistics and Cultural Studies
- Spacecraft and Cryogenic Technologies
- Experimental and Theoretical Physics Studies
- Astrophysics and Star Formation Studies
- Space Science and Extraterrestrial Life
- Isotope Analysis in Ecology
- Space Exploration and Technology
- Gamma-ray bursts and supernovae
- earthquake and tectonic studies
- Sports Dynamics and Biomechanics
- Space exploration and regulation
- Geomagnetism and Paleomagnetism Studies
- Spacecraft Dynamics and Control
- Geophysics and Gravity Measurements
- Radioactivity and Radon Measurements
- Earthquake Detection and Analysis
- Engineering and Agricultural Innovations
University of Colorado Boulder
2018-2021
Lockheed Martin (United States)
2020
University of Colorado System
2018-2019
Technion – Israel Institute of Technology
2017
The gravity field of a small body provides insight into its internal mass distribution. We used two approaches to measure the rubble-pile asteroid (101955) Bennu: (i) tracking and modeling spacecraft in orbit about (ii) pebble-sized particles naturally ejected from Bennu's surface sustained orbits. These yield statistically consistent results up degree order 3, with particle-based being significant 9. Comparisons constant-density shape model show that Bennu has heterogeneous deviations can...
Abstract In early 2019, the OSIRIS‐REx spacecraft discovered small particles being ejected from surface of near‐Earth asteroid Bennu.sww Although they were seen to be at slow speeds, on order tens cm/s, a number surprisingly orbit for multiple revolutions and days, which requires dynamical mechanism quickly substantially modify prevent re‐impact upon their first periapse passage. This paper demonstrates that, based simulations constrained by conditions observed events, combined effects...
The Near-Earth Asteroid Characterization and Observation (NEACO) mission is a concept study proposing to explore the fast-rotating asteroid (469219) 2016 , one of Earth's few quasi-satellites. In this study, SmallSat spacecraft performs scientific investigation that characterizes at sufficient degree enable future, more in-depth missions. 166 kg NEACO uses low-thrust, solar electric propulsion system reach within 22 months from launch. Its instrument suite consists two optical cameras,...
Abstract This paper explores the implications of observed Bennu particle ejection events for that asteroid's spin rate and orbit evolution, which could complicate interpretation Yarkovsky‐O'Keefe‐Radzievskii‐Paddack (YORP) Yarkovsky effects on this body's orbital evolution. Based current estimates rates, we find overall contribution to Bennu's drift is small or negligible as compared YORP effects. However, if there a large unseen component smaller mass ejections strong directionality in...
The dynamics of asteroid deflection and manipulation using mass ejection are examined. First, a linearized small angular velocity inertia tensor deviation model for close-to-principal-axis rotators is developed. then applied to launching boulders off surfaces, proving that the principal-axis-rotator characteristic can be kept while removing material surface. Mass ejections presented This method, dubbed driver deflection, uses discrete launches masses an prevent its collision with Earth. By...
High area-to-mass ratio space objects at geosynchronous orbits pose a threat to operational satellites because of the difficulty in tracking them from Earth. This paper develops an in-orbit onboard algorithm for high objects. The design uses relative motion dynamics and simplified stereocamera measurement model estimate tracked object’s position velocity, as well its solar radiation pressure coefficient. An underlying assumption is dominance perturbation, which confirmed using analysis...
An investigation into the effects of momentum transfer deflection methods, specifically kinetic impact and nuclear detonation, on rotational state a deflected object is presented. Initially, simplified model developed applied ellipsoid analogs. The then expanded to, on, polyhedral asteroid shapes. results show presence side to rotation, introduction precession, change in angular velocity magnitude, with existence lever arm between direction interface location respect body’s center mass. At...