A5064302947- Astro and Planetary Science
- Planetary Science and Exploration
- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Geology and Paleoclimatology Research
- Congenital limb and hand anomalies
- Oral Health Pathology and Treatment
- Astronomical Observations and Instrumentation
- Geological and Geochemical Analysis
- Solar and Space Plasma Dynamics
- High-pressure geophysics and materials
- Isotope Analysis in Ecology
- earthquake and tectonic studies
- Rangeland Management and Livestock Ecology
- Astrophysics and Cosmic Phenomena
- Space exploration and regulation
- Space Exploration and Technology
- Dark Matter and Cosmic Phenomena
- Image Processing and 3D Reconstruction
- Ionosphere and magnetosphere dynamics
- Genital Health and Disease
- Material Science and Thermodynamics
- Nuts composition and effects
- Atmospheric aerosols and clouds
- Electron and X-Ray Spectroscopy Techniques
Imperial College London
1972-2013
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...
On September 26, 2022, NASA's Double Asteroid Redirection Test (DART) mission successfully impacted Dimorphos, the natural satellite of binary near-Earth asteroid (65803) Didymos. Numerical simulations impact provide a means to explore target surface material properties and structures, consistent with observed momentum deflection efficiency, ejecta cone geometry, ejected mass. Our simulation, which best matches observations, indicates that Dimorphos is weak, cohesive strength less than few...
Abstract Asteroid shapes and hydration levels can serve as tracers of their history origin. For instance, the asteroids (162173) Ryugu (101955) Bennu have an oblate spheroidal shape with a pronounced equator, but contain different surface levels. Here we show, through numerical simulations large asteroid disruptions, that spheroids, some which equator defining spinning top shape, form directly gravitational reaccumulation. We further show rubble piles formed in single disruption similar...
Asteroids with diameters less than about 5 km have complex histories because they are small enough for radiative torques, YORP, to be a notable factor in their evolution. (152830) Dinkinesh is asteroid orbiting the Sun near inner edge of Main Asteroid Belt heliocentric semimajor axis 2.19 AU; its S type spectrum typical bodies this part Belt. Here we report observations by Lucy spacecraft as it passed within 431 Dinkinesh. revealed Dinkinesh, which has an effective diameter only $\sim$720 m,...
We model the infrared emission from zodiacal dust detected by IRAS and COBE missions, with aim of estimating relative contributions asteroidal, cometary interstellar to cloud.Our most important result is detection an isotropic component foreground radiation due dust.The in inner solar system known have a fan-like distribution.If this assumed extend orbit Mars, we find that cometary, asteroidal account for 70%, 22% 7.5% fan.We worse fit if fan Jupiter.Our broadly consistent analysis Divine...
The binary asteroid 65803 Didymos-Dimorphos is the target of first deflection test (NASA's Double Asteroid Redirection Test, DART) and system that will be characterized by a rendezvous mission (ESA's Hera). cohesive strength fast-spin-primary Didymos key factor could affect impact outcome stability this system. To support preparation data interpretation these missions gain better understanding formation evolution system, we investigate structural based on current observational information....
The Cold Classical Kuiper Belt, a class of small bodies in undisturbed orbits beyond Neptune, are primitive objects preserving information about Solar System formation. New Horizons spacecraft flew past one these objects, the 36 km long contact binary (486958) Arrokoth (2014 MU69), January 2019. Images from flyby show that has no detectable rings, and satellites (larger than 180 meters diameter) within radius 8000 km, lightly-cratered smooth surface with complex geological features, unlike...
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...
An experiment to record the spectrum of Zodiacal Light in neighbourhood Mg I absorption line (5183.6 Å) is described. Measurements were made Doppler shift imposed on by motion interplanetary dust particles. Observations concentrated ecliptic plane, spectra being obtained at lower elongation angles from Sun than previously achieved, and also over entire range high elongations including Gegenschein.
Abstract On September 26, 2022, NASA's Double Asteroid Redirection Test (DART) mission successfully impacted Dimorphos, the natural satellite of binary near-Earth asteroid (65803) Didymos. Numerical simulations impact provide a means to explore target surface material properties and structures, consistent with observed momentum deflection efficiency, ejecta cone geometry, ejected mass. Our simulation that best matches observations indicates Dimorphos is weak (less than few Pa), similar...