Search Publications
Arecibo radar observations of near-Earth asteroid (3200) Phaethon during the 2017 apparition
Bhiravarasu, Sriram S.; Benner, Lance A. M.; Giorgini, Jon D. +8 more
We report Arecibo S-band (2380 MHz; 12.6 cm) radar observations of near-Earth asteroid (3200) Phaethon during the December 2017 apparition when Phaethon passed within 0.07 au of Earth. Radar images with a resolution of 75 m per pixel reveal a roughly spheroidal shape more than 6 km in diameter at the equator with several discernible surface featur…
Automated crater detection on Mars using deep learning
Lee, Christopher
Impact crater cataloging is an important tool in the study of the geological history of planetary bodies in the Solar System, including dating of surface features and geologic mapping of surface processes. Catalogs of impact craters have been created by a diverse set of methods over many decades, including using visible or near infra-red imagery a…
Dusk over dawn O2 asymmetry in Europa's near-surface atmosphere
Johnson, Robert E.; Chaufray, Jean-Yves; Oza, Apurva V. +4 more
The evolution of Europa's water-product exosphere over its 85-h day, based on current models, has not been shown to exhibit any diurnal asymmetries. Here we simulate Europa's exosphere using a 3-D Monte Carlo routine including, for the first time, the role of Europa's rotation on the evolution of exospheric molecules tracked throughout the orbit. …
A comparative study of size frequency distributions of Jupiter Trojans, Hildas and main belt asteroids: A clue to planet migration history
Terai, Tsuyoshi; Takato, Naruhisa; Ohtsuki, Keiji +4 more
Since 2002, we have obtained size frequency distributions (SFDs) of main belt asteroids (MBAs), Hildas, and Jupiter Trojans (JTs) by using the 8.2-m Subaru Telescope equipped with the wide-field CCD cameras: Suprime-Cam (SC) or Hyper Suprime-Cam (HSC). After combining these SFDs with SFDs obtained from other surveys, we performed a comparative stu…
Identification of organic molecules with a laboratory prototype based on the Laser Ablation-CosmOrbitrap
Engrand, C.; Vuitton, V.; Briois, C. +18 more
In the Solar System, extra-terrestrial organic molecules have been found on cometary primitive objects, on Titan and Enceladus icy moons and on Mars. Identification could be achieved for simple organic species by remote sensing based on spectroscopic methods. However in situ mass spectrometry is a key technology to determine the nature of more com…
Study of morphology and degradation of lunar craters using Chandrayaan-1 data
Srivastava, Pradeep; Jain, Vikrant; Khanna, Nitin +2 more
Impact craters are essential and dominant features of the lunar surface. Under the presence of a very thin atmosphere, the degradation of the lunar craters takes place possibly due to gravity, slope processes, or solar wind weathering. Hence, these craters act as tools to understand the properties and processes of the lunar surface. Our analysis i…
A New South Polar Digital Terrain Model of Mars from the High-Resolution Stereo Camera (HRSC) onboard the ESA Mars Express
Muller, Jan-Peter; Putri, Alfiah Rizky Diana; Sidiropoulos, Panagiotis +2 more
The first high-resolution Digital Terrain Model (DTM) of the entire South Pole of Mars has been produced. A modified version (Kim and Muller, 2009) of a NASA-VICAR-based pipeline developed by DLR (German Aerospace Centre) and JPL (Jet Propulsion Laboratory) has been employed with image matching based on the Gotcha (Gruen-Otto-Chau) algorithm (Shin…
Re-reduction of CCD astrometric observations of Neptunian satellites in 2006-2007 based on Gaia DR2 and comparison with ephemerides
Cheng, X.; Yan, D.; Qiao, R. C. +3 more
Based on the newly released Gaia DR2 star catalogue, the CCD images of Neptunian satellites taken by the telescopes at Xinglong Observatory of National Astronomical Observatory in 2006-2007 were re-reduced. A total of 174 satellite positions were derived, including 34 new observed positions of Triton, 28 new and 112 updated observed positions of N…
New phase-magnitude curves for some main belt asteroids, fit of different photometric systems and calibration of the albedo - Photometry relation
Cellino, A.; Carbognani, A.; Caminiti, S.
Results of photometric observations of a small sample of selected Main Belt asteroids are presented. The obtained measurements can be used to achieve a better calibration of the asteroid photometric system (H, G1 , G2) adopted by the IAU, and to make comparisons with best-fit curves that can be obtained using different photom…
New CCD astrometric observations of the five major uranian satellites using Gaia DR1 in 2014-2016
Vienne, A.; Wang, N.; Peng, Q. Y. +4 more
710 CCD frames, observed by 1-m telescope at Yunnan Observatory over 15 nights, have been reduced to derive new precise positions of the five Uranian major satellites (Ariel, Umbriel, Titania, Oberon and Miranda). In the pixel positional measurement of the faint satellites near Uranus, a halo removal procedure similar to that of Veiga et al. (Veig…