Search Publications
The morphological, elastic, and electric properties of dust aggregates in comets: A close look at COSIMA/Rosetta's data on dust in comet 67P/Churyumov-Gerasimenko
Kimura, Hiroshi; Merouane, Sihane; Paquette, John +2 more
The Cometary Secondary Ion Mass Analyzer (COSIMA) onboard ESA's Rosetta orbiter has revealed that dust particles in the coma of comet 67P/Churyumov-Gerasimenko are aggregates of small grains. We study the morphological, elastic, and electric properties of dust aggregates in the coma of comet 67P/Churyumov-Gerasimenko using optical microscopic imag…
Automated detection of block falls in the north polar region of Mars
Oberst, J.; Hauber, E.; Gwinner, K. +1 more
We developed a change detection method for the identification of ice block falls using NASA's HiRISE images of the north polar scarps on Mars. Our method is based on a Support Vector Machine (SVM), trained using Histograms of Oriented Gradients (HOG), and blob detection. The SVM detects potential new blocks between a set of images; the blob detect…
Mapping and spatial statistical analysis of Mars Yardangs
Di, Kaichang; Liu, Bin; Liu, Jia +4 more
Mars yardang fields were mapped using the newly available high-resolution Context Camera (CTX) mosaics (30°N to 30°S) through visual interpretation and manual digitization. We classified the Martian yardangs into three types according to their shapes: long ridge, inverted hull and curvilinear shapes, and found that the number of long ridge yardang…
A new method for determining the total electron content in Mars' ionosphere based on Mars Express MARSIS data
Witasse, Olivier; Sánchez-Cano, Beatriz; Kofman, Wlodek +5 more
We present a new method for determining the total electron content (TEC) in the Martian ionosphere based on the time delay of received radar pulses of the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) on board the Mars Express spacecraft. Previous studies of the same dataset have produced differing results for the day-side i…
Porosity gradients as a means of driving lateral flows at cometary surfaces
Thomas, Nicolas; Christou, Chariton; Dadzie, S. Kokou +1 more
The Rosetta spacecraft has provided invaluable and unexpected information about cometary outgassing. The on-board instruments ROSINA, MIRO, and VIRTIS showed non-uniform outgassing of H2O over the surface of the nucleus. Rarefied gas flows display remarkable flow phenomena that may help explain diverse physical observations and models h…
Basaltic fissure types on Earth: Suitable analogs to evaluate the origins of volcanic terrains on the Moon and Mars?
Kobs Nawotniak, Shannon E.; Hughes, Scott S.; Elphic, Richard C. +6 more
Basaltic eruptive fissures of the Great Rift and surroundings on the eastern Snake River Plain of Idaho, USA, and selected volcanic features in Hawai'i, Iceland and northern Africa were surveyed for their relevancy as planetary analogs. Evaluated during field investigations and in satellite imagery for structures, physiography, and geologic settin…
Linking studies of tiny meteoroids, zodiacal dust, cometary dust and circumstellar disks
Lasue, J.; Milli, J.; Levasseur-Regourd, A. C. +2 more
Tiny meteoroids entering the Earth's atmosphere and inducing meteor showers have long been thought to originate partly from cometary dust. Together with other dust particles, they form a huge cloud around the Sun, the zodiacal cloud. From our previous studies of the zodiacal light, as well as other independent methods (dynamical studies, infrared …
Lithological mapping of Eratosthenes crater region using Moon Mineralogy Mapper of Chandrayaan-1
Kumaresan, P. R.; Saravanavel, J.; Palanivel, K.
Selenological exploration (lunar geology) involves mapping and delineation of different rock types and minerals present in the Moon. Various lunar missions with multi-spectral sensors provided preliminary information about the lithological and mineralogical occurrences on the Moon. The Chandrayaan-1 Moon Mineralogy Mapper (M3), provided…
Pyroxene chemistry and crystallization history of basaltic units in the Mare Humorum on the nearside of the Moon: Implications for the volcanic history of the region
Rajesh, V. J.; Thesniya, P. M.
Mare basalts are volcanic features on the lunar surface and are vital for understanding the Moon's volcanic and thermal history. The present study investigates the mineralogy and chemical variations of the mare basaltic units in the Mare Humorum on the Moon's nearside using orbital remote sensing data from recent lunar exploration missions. The pr…
Optical properties of cometary particles collected by COSIMA: Assessing the differences between microscopic and macroscopic scales
Langevin, Y.; Schulz, R.; Hilchenbach, M. +6 more
The COSIMA mass spectrometer on-board Rosetta was equipped with an optical microscope, Cosiscope, which identified several 10,000 cometary particles collected on targets exposed during the orbital phase around the nucleus of comet 67P Churyumov-Gerasimenko. The median value of reflectance factors evaluated from Cosiscope images for large collected…