Chikatoshi Honda
A5056193766- Astro and Planetary Science
- Planetary Science and Exploration
- Isotope Analysis in Ecology
- Geology and Paleoclimatology Research
- Space Exploration and Technology
- Space Science and Extraterrestrial Life
- Geological and Geochemical Analysis
- earthquake and tectonic studies
- Stellar, planetary, and galactic studies
- Satellite Image Processing and Photogrammetry
- Landslides and related hazards
- Image Processing and 3D Reconstruction
- Space Satellite Systems and Control
- Methane Hydrates and Related Phenomena
- Geological Modeling and Analysis
- Maritime and Coastal Archaeology
- Infrared Target Detection Methodologies
- Space exploration and regulation
- Calibration and Measurement Techniques
- Geophysics and Gravity Measurements
- Inertial Sensor and Navigation
- Atmospheric Ozone and Climate
- Marine and environmental studies
- Astronomical Observations and Instrumentation
- Urban and spatial planning
Ehime University
2024
University of Aizu
2014-2023
Kōchi University
2019-2021
Kindai University
2020
Akebono (Japan)
2020
Institute of Space and Astronautical Science
2006-2014
Japan Aerospace Exploration Agency
2006-2009
National Institute for Environmental Studies
2008
Brown University
2008
NTT (Japan)
2008
The Hayabusa2 spacecraft arrived at the near-Earth carbonaceous asteroid 162173 Ryugu in 2018. We present observations of Ryugu's shape, mass, and geomorphology. has an oblate "spinning top" with a prominent circular equatorial ridge. Its bulk density, 1.19 ± 0.02 grams per cubic centimeter, indicates high-porosity (>50%) interior. Large surface boulders suggest rubble-pile structure. Surface slope analysis shows shape may have been produced from having once spun twice current rate. Coupled...
Hayabusa2 at the asteroid Ryugu Asteroids fall to Earth in form of meteorites, but these provide little information about their origins. The Japanese mission is designed collect samples directly from surface an and return them for laboratory analysis. Three papers this issue describe team's study near-Earth carbonaceous 162173 Ryugu, which spacecraft arrived June 2018 (see Perspective by Wurm). Watanabe et al. measured asteroid's mass, shape, density, showing that it a “rubble pile” loose...
Hayabusa2 at the asteroid Ryugu Asteroids fall to Earth in form of meteorites, but these provide little information about their origins. The Japanese mission is designed collect samples directly from surface an and return them for laboratory analysis. Three papers this issue describe team's study near-Earth carbonaceous 162173 Ryugu, which spacecraft arrived June 2018 (see Perspective by Wurm). Watanabe et al. measured asteroid's mass, shape, density, showing that it a “rubble pile” loose...
The Hayabusa2 spacecraft investigated the small asteroid Ryugu, which has a rubble-pile structure. We describe an impact experiment on Ryugu using Hayabusa2's Small Carry-on Impactor. produced artificial crater with diameter >10 meters, semicircular shape, elevated rim, and central pit. Images of resulting ejecta were recorded by Deployable CAMera 3 for >8 minutes, showing growth curtain (the outer edge ejecta) deposition onto surface. was asymmetric heterogeneous it never fully detached...
Abstract C-type asteroids 1 are considered to be primitive small Solar System bodies enriched in water and organics, providing clues the origin evolution of building blocks life. asteroid 162173 Ryugu has been characterized by remote sensing 2–7 on-asteroid measurements 8,9 with Hayabusa2 (ref. 10 ). However, ground truth provided laboratory analysis returned samples is invaluable determine fine properties other planetary bodies. We report preliminary results analyses on from particle size...
Carbonaceous meteorites are thought to be fragments of C-type (carbonaceous) asteroids. Samples the asteroid (162173) Ryugu were retrieved by Hayabusa2 spacecraft. We measured mineralogy and bulk chemical isotopic compositions samples. The samples mainly composed materials similar those carbonaceous chondrite meteorites, particularly CI (Ivuna-type) group. consist predominantly minerals formed in aqueous fluid on a parent planetesimal. primary altered fluids at temperature 37° ± 10°C, about...
The Hayabusa2 spacecraft collected samples from the surface of carbonaceous near-Earth asteroid (162173) Ryugu and brought them to Earth. were expected contain organic molecules, which record processes that occurred in early Solar System. We analyzed molecules extracted samples. identified a variety containing atoms CHNOS, formed by methylation, hydration, hydroxylation, sulfurization reactions. Amino acids, aliphatic amines, carboxylic polycyclic aromatic hydrocarbons, nitrogen-heterocyclic...
Presented here are the observations and interpretations from a comprehensive analysis of 16 representative particles returned C-type asteroid Ryugu by Hayabusa2 mission. On average consist 50% phyllosilicate matrix, 41% porosity 9% minor phases, including organic matter. The abundances 70 elements in close agreement with those CI chondrites. Bulk show higher δ18O, Δ17O, ε54Cr values than As such, sampled most primitive least-thermally processed protosolar nebula reservoirs. Such finding is...
The Hayabusa2 spacecraft investigated the C-type (carbonaceous) asteroid (162173) Ryugu. mission performed two landing operations to collect samples of surface and subsurface material, latter exposed by an artificial impact. We present images second touchdown site, finding that ejecta from impact crater was at sample location. Surface pebbles both sites show morphological variations ranging rugged smooth, similar Ryugu's boulders, shapes quasi-spherical flattened. were returned Earth on 6...
Abstract Volatile and organic-rich C-type asteroids may have been one of the main sources Earth’s water. Our best insight into their chemistry is currently provided by carbonaceous chondritic meteorites, but meteorite record biased: only strongest types survive atmospheric entry are then modified interaction with terrestrial environment. Here we present results a detailed bulk microanalytical study pristine Ryugu particles, brought to Earth Hayabusa2 spacecraft. particles display close...
Samples of the carbonaceous asteroid (162173) Ryugu were collected and brought to Earth by Hayabusa2 spacecraft. We investigated macromolecular organic matter in samples found that it contains aromatic aliphatic carbon, ketone, carboxyl functional groups. The spectroscopic features are consistent with those chemically primitive chondrite meteorites experienced parent-body aqueous alteration (reactions liquid water). morphology carbon includes nanoglobules diffuse associated phyllosilicate...
Rendezvous of the Japanese spacecraft Hayabusa with near-Earth asteroid 25143 Itokawa took place during interval September through November 2005. The onboard camera imaged solid surface this tiny (535 meters by 294 209 meters) a spatial resolution 70 centimeters per pixel, revealing diverse morphologies. Unlike previously explored asteroids, reveals both rough and smooth terrains. Craters generally show unclear Numerous boulders on Itokawa's suggest rubble-pile structure.
Abstract The Moon is the nearest celestial body to Earth. Understanding most important issue confronting geosciences and planetary sciences. Japan will launch lunar polar orbiter SELENE (Kaguya) (Kato et al. , 2007) in 2007 as first mission of Japanese long-term exploration program acquire data for scientific knowledge possible utilization Moon. An optical sensing instrument called Lunar Imager/Spectrometer (LISM) loaded on SELENE. LISM requirements project are intended provide...
We determined model ages of mare deposits on the farside Moon basis crater frequency distributions in 10-meter-resolution images obtained by Terrain Camera SELENE (Selenological and Engineering Explorer) (Kaguya). Most volcanism that formed lunar ceased at approximately 3.0 billion years ago, suggesting was markedly reduced globally during this period. However, several various locations also show a much younger age, clustering 2.5 ago. These young indicate lasted longer than previously...
In 2018, the Japanese spacecraft Hayabusa2, arrived at small asteroid Ryugu. The surface of this C-type is covered with numerous boulders whose size and shape distributions are investigated in study. Using a few hundred Optical Navigation Camera (ONC) images pixel scale approximately 0.65 m, we focus on greater than 5 m diameter. Smaller also considered using five arbitrarily chosen ONC close-up scales ranging from 0.7 to 6 cm. Across entire area (~2.7 km2) Ryugu, nearly 4400 larger were...
Without a protective atmosphere, space-exposed surfaces of airless Solar System bodies gradually experience an alteration in composition, structure and optical properties through collective process called space weathering. The return samples from near-Earth asteroid (162173) Ryugu by Hayabusa2 provides the first opportunity for laboratory study space-weathering signatures on most abundant type inner solar system body: C-type asteroid, composed materials largely unchanged since formation...
The near-Earth carbonaceous asteroid (162173) Ryugu is expected to contain volatile chemical species that could provide information on the origin of Earth's volatiles. Samples were retrieved by Hayabusa2 spacecraft. We measured noble gas and nitrogen isotopes in samples found they are dominated presolar primordial components, incorporated during Solar System formation. Noble concentrations higher than those Ivuna-type (CI) chondrite meteorites. Several host phases isotopically distinct have...
Abstract The surface of asteroid 25143 Itokawa is covered with numerous boulders although gravity very small compared that other asteroids previously observed from spacecraft. Here we report the size-frequency statistics on entire based high-resolution images (1 pixel ≈0.4 m) obtained by Hayabusa There are 373 larger than 5 m in mean horizontal dimension surface—0.393 km 2 —and number density nearly 10 3 /km . cumulative boulder size distribution has a power-index −3.1 ± 0.1. For east and...
Abstract The Multiband Imager (MI) is one of the 14 instruments for Japanese SELENE (KAGUYA) mission. Goal mission to understand origin and evolution Moon by obtaining global element mineral compositions, topological structure, gravity field whole Moon, electromagnetic particle environment Moon. MI designed be a high-resolution multiband imaging camera with spatial resolution in visible bands 20 m near-infrared 62 from 100 km orbit altitude. flight model has been manufactured integrated....
The Spectral Profiler (SP) onboard the Japanese SELENE (KAGUYA) spacecraft is now providing global high spectral resolution visible‐near infrared continuous reflectance spectra of Moon. impact craters on farside Moon reveal lithologies that were not previously identified. achievements SP so far include: most definite detection crystalline iron‐bearing plagioclase with its characteristic 1.3 μ m absorption band Moon; a new interpretation lithology Tsiolkovsky crater central peaks, classified...