Michael C. Moreau
A5091513670- Astro and Planetary Science
- Planetary Science and Exploration
- GNSS positioning and interference
- Inertial Sensor and Navigation
- Space Satellite Systems and Control
- Isotope Analysis in Ecology
- Spacecraft Dynamics and Control
- Spacecraft Design and Technology
- Advanced Frequency and Time Standards
- Nuclear Physics and Applications
- Geophysics and Gravity Measurements
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Space Exploration and Technology
- Pulsars and Gravitational Waves Research
- Spacecraft and Cryogenic Technologies
- Radio Astronomy Observations and Technology
- Nuts composition and effects
- Fluid Dynamics Simulations and Interactions
- Stellar, planetary, and galactic studies
- Space exploration and regulation
- Ionosphere and magnetosphere dynamics
- Geological and Geochemical Analysis
- Experimental and Theoretical Physics Studies
- Library Science and Administration
Goddard Space Flight Center
2015-2025
University of Arizona
2018
Planetary Science Institute
2018
Indiana University Bloomington
2013
Glendale Community College
2002
Active asteroids are those that show evidence of ongoing mass loss. We report repeated instances particle ejection from the surface (101955) Bennu, demonstrating it is an active asteroid. The events were imaged by OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer) spacecraft. For three largest observed events, we estimated ejected velocities sizes, event times, source regions, energies. also determined trajectories photometric properties...
Carbonaceous asteroids, such as (101955) Bennu, preserve material from the early Solar System, including volatile compounds and organic molecules. We report spacecraft imaging spectral data collected during after retrieval of a sample Bennu’s surface. The sampling event mobilized rocks dust into debris plume, excavating 9-meter-long elliptical crater. This exposed is darker, spectrally redder, more abundant in fine particulates than original bulk density displaced subsurface was 500 to 700...
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 We analyze the trajectories of 313 particles seen in near‐Bennu environment between December 2018 and September 2019. Of these, 65% follow suborbital trajectories, 20% undergo more than one orbital revolution around asteroid, 15% directly escape on hyperbolic trajectories. The median lifetime these is ∼6 hr. are sensitive to Bennu's gravitational field, which allows us reliably estimate spherical harmonic coefficients through degree 8 resolve nonuniform mass distribution 3....
The GPS Antenna Characterization Experiment (GPS ACE) has made extensive observations of L1 signals received at geosynchronous (GEO) altitude, with the objective developing comprehensive models signal levels and performance in transmit antenna side lobes. ACE architecture been place collecting extreme sensitivity for several years, enabling accumulation full azimuthal coverage gain patterns over time. Results discussed this paper include reconstructed patterns, comparison available preflight...
Abstract The OSIRIS‐REx mission returned a sample of regolith from the carbonaceous asteroid Bennu in September 2023. We present preliminary situ investigations petrology and petrography selected particles ranging size 0.5 to 3 mm. Using combination optical electron beam techniques, we investigate whole specimens polished sections belonging morphologically visually distinct categories particles. find that morphological differences are reflective petrographic petrologic differences, leading...
Abstract The Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer (OSIRIS-REx) spacecraft mission characterized collected a sample from asteroid (101955) Bennu. After the OSIRIS-REx Sample Return Capsule released to Earth’s surface in 2023 September, diverted into new orbit that encounters (99942) Apophis 2029, enabling second with same unique capabilities: OSIRIS–Apophis (APEX). On 2029 April 13, 340 m diameter will draw within ∼32,000 km of surface,...
In September of 2016, the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security, Regolith EXplorer) spacecraft will depart for asteroid (101955) Bennu, and when it does, humanity turn an important corner in exploration Solar System. After arriving at Fall 2018, undertake a program observations designed to select site suitable retrieving sample that be returned Earth 2023. The third mission NASA's New Frontiers program, obtain minimum 60 g primitive asteroid's...
Abstract OSIRIS‐REx began observing particle ejection events shortly after entering orbit around near‐Earth asteroid (101955) Bennu in January 2019. For some of these events, the only observations ejected particles come from first two images taken immediately event by OSIRIS‐REx's NavCam 1 imager. Without three or more each particle, traditional determination is not possible. However, assuming that all at same time and location for a given event, approximating their velocities remained...
This work examines the autonomous navigation accuracy achievable for a lunar exploration trajectory from translunar libration point relay satellite, augmented by signals Global Positioning System (GPS). We also provide brief analysis comparing to orbit architectures, and discuss some issues of GPS usage cis-lunar trajectories.
The OSIRIS-REx mission has observed multiple instances of particles being ejected from the surface near-Earth asteroid (101955) Bennu. ability to quickly identify particle trajectories and origins is necessary following a ejection event. Using proven initial orbit determination techniques, we can rapidly estimate locations. We present current results pertaining identification tracks, an evaluation estimated orbits excess velocity induce surface, uncertainty quantification location. energies...
ABSTRACT: GPS is an enabling technology for autonomous spacecraft navigation, including mission concepts involving formation flying in highly eccentric orbits. However, to date most spaceborne applications have been limited low earth orbits or postprocessing applications. This paper describes the problems associated with using high orbit (HEO) environment and presents a receiver design optimized these The builds upon PiVoT developed by Goddard Space Flight Center incorporating Enhanced Orbit...