Results 61 to 70 of about 394,300 (243)

The Dynamical State of the Didymos System before and after the DART Impact

The Planetary Science Journal
NASA’s Double Asteroid Redirection Test (DART) spacecraft impacted Dimorphos, the natural satellite of (65803) Didymos, on 2022 September 26, as a first successful test of kinetic impactor technology for deflecting a potentially hazardous object in space.
Derek C. Richardson, Harrison F. Agrusa, Brent Barbee, Rachel H. Cueva, Fabio Ferrari, Seth A. Jacobson, Rahil Makadia, Alex J. Meyer, Patrick Michel, Ryota Nakano, Yun Zhang, Paul Abell, Colby C. Merrill, Adriano Campo Bagatin, Olivier Barnouin, Nancy L. Chabot, Andrew F. Cheng, Steven R. Chesley, R. Terik Daly, Siegfried Eggl, Carolyn M. Ernst, Eugene G. Fahnestock, Tony L. Farnham, Oscar Fuentes-Muñoz, Edoardo Gramigna, Douglas P. Hamilton, Masatoshi Hirabayashi, Martin Jutzi, Josh Lyzhoft, Riccardo Lasagni Manghi, Jay McMahon, Fernando Moreno, Naomi Murdoch, Shantanu P. Naidu, Eric E. Palmer, Paolo Panicucci, Laurent Pou, Petr Pravec, Sabina D. Raducan, Andrew S. Rivkin, Alessandro Rossi, Paul Sánchez, Daniel J. Scheeres, Peter Scheirich, Stephen R. Schwartz, Damya Souami, Gonzalo Tancredi, Paolo Tanga, Paolo Tortora, Josep M. Trigo-Rodríguez, Kleomenis Tsiganis, John Wimarsson, Marco Zannoni   +52 more
doaj   +1 more source

Radar contributions to asteroid astrometry and dynamics [PDF]

CELESTIAL MECHANICS AND DYNAMICAL ASTRONOMY, 1997
Almost every radar observation of asteroids has measured some characteristics of the distribution of echo power in time delay (range) and Doppler frequency (radial velocity). Such measurements, which are orthogonal to optical plane-of-sky angular astrometry, are also done in the well-known, “absolute” reference frame of the planetary ephemerides, often
openaire   +2 more sources

Tools for Learning—Promoting Reflection for Student Teachers' Development of PCK

Journal of Research in Science Teaching, EarlyView.
ABSTRACT This paper investigates how the coherent integration of three different tools for reflection during a science methods course can contribute to student teachers' planning and enactment of science teaching, that is, their development of pedagogical content knowledge (PCK).
Pernilla Nilsson, Anne‐Marie Cederqvist   +1 more
wiley   +1 more source

Relative Equilibria and Periodic Orbits in a Binary Asteroid Model [PDF]

arXiv, 2023
We present a planar four-body model, called the Binary Asteroid Problem, for the motion of two asteroids (having small but positive masses) moving under the gravitational attraction of each other, and under the gravitational attraction of two primaries (with masses much larger than the two asteroids) moving in uniform circular motion about their center
arxiv  

System Modeling and Simulation of TianWen-2 Sampling on an Asteroid Regolith Surface

Space: Science & Technology
As China’s first asteroid exploration mission, the TianWen-2 spacecraft mainly focuses on surface sampling on the near-Earth asteroid 2016 HO3. Different from the usual sampling strategy of releasing a small lander or ejecting a projectile, the whole ...
He Zhang, Dongming Ge, Runran Deng, Cuicui Liu, Fan Guo, Yingqiao Xu, Fuming Zeng, Jinchang Hu, Yuanjie Zou, Weiwei Gong, Wei E   +10 more
doaj   +1 more source

DYNAMICS AROUND AN ASTEROID MODELED AS A MASS TRIPOLE [PDF]

Revista Mexicana de Astronomía y Astrofísica, 2020
The orbital dynamics of a spacecraft orbiting around irregular small celestial bodies is a challenging problem. Diffculties to model the gravity field of these bodies arise from the poor knowledge of the exact shape as observed from the Earth. In order to understand the complex dynamical environment in the vicinity of irregular asteroids, several ...
Santos, L. B.T., Marchi, L. O., Sousa-Silva, P. A., Sanchez, D. M., Aljbaae, S., Prado, A. F.B.A.   +5 more
openaire   +4 more sources

Big Cat Mortality in Subsistence Hunts in Amazonia 亚马孙雨林地区生计狩猎中的大型猫科动物致死情况研究

Wildlife Letters, EarlyView.
We use data from a participatory biodiversity monitoring program to estimate the annual mortality of jaguars and pumas resulting from subsistence hunts in two Amazonian Extractive Reserves. We estimate that around 50 big cats are killed annually in the study area, which is consistent with an independent estimate for the same area and within the same ...
Elildo A. R. Carvalho Jr., Cíntia K. M. Lopes, Milton J. de Paula, Juarez C. B. Pezzuti   +3 more
wiley   +1 more source

BYORP and Dissipation in Binary Asteroids: Lessons from DART

The Planetary Science Journal
The near-Earth binary asteroid Didymos was the target of the planetary defense demonstration mission DART in 2022 September. The smaller binary component, Dimorphos, was impacted by the spacecraft in order to measure momentum transfer in kinetic impacts ...
Matija Ćuk, Harrison Agrusa, Rachel H. Cueva, Fabio Ferrari, Masatoshi Hirabayashi, Seth A. Jacobson, Jay McMahon, Patrick Michel, Paul Sánchez, Daniel J. Scheeres, Stephen Schwartz, Kevin J. Walsh, Yun Zhang   +12 more
doaj   +1 more source

Stability of a Flexible Asteroid Lander with Landing Control

Aerospace, 2022
Stable landing on asteroids is of considerable scientific and economic value but accompanied by huge difficulties. This paper proposes a novel flexible lander suitable for asteroids with microgravity and rugged surface.
Weifeng Yan, Ruoyu Feng, Hexi Baoyin
doaj   +1 more source

Dynamical evolution of cometary asteroids [PDF]

Monthly Notices of the Royal Astronomical Society, 1998
ABSTRA C T We present results from long-term numerical integrations of hypothetical Jupiter-family comets (JFCs) over time-scales in excess of the estimated cometary active lifetime. During inactive periods these bodies could be considered as ‘cometary’ near-Earth objects (NEOs) or ‘cometary asteroids’. The contribution of cometary asteroids to the NEO
N. W. Harris, M. E. Bailey
openaire   +2 more sources