Results 41 to 50 of about 3,161,815 (352)

Effect of lunar gravity models on Chang'E-2 orbit determination using VLBI tracking data

Geodesy and Geodynamics, 2016
The precise orbit determination of Chang'E-2 is the most important issue for successful mission and scientific applications, while the lunar gravity field model with big uncertainties has large effect on Chang'E-2 orbit determination.
Erhu Wei, Xuechuan Li, Shuanggen Jin, Jingnan Liu   +3 more
doaj   +1 more source

Correction Method for the Observed Global Navigation Satellite System Ultra-Rapid Orbit Based on Dilution of Precision Values

Sensors, 2018
For ultra-rapid orbits provided by the Global Navigation Satellite System (GNSS), the key parameters, accuracy and timeliness, must be taken into consideration in real-time and near real-time applications.
Qianxin Wang, Chao Hu, Ya Mao
doaj   +1 more source

Research on the Rotational Correction of Distributed Autonomous Orbit Determination in the Satellite Navigation Constellation

Remote Sensing, 2022
The autonomous orbit determination of the navigation constellation uses only bidirectional ranging data of the inter-satellite link for data processing.
Wei Zhou, Hongliang Cai, Ziqiang Li, Chengpan Tang, Xiaogong Hu, Wanke Liu   +5 more
doaj   +1 more source

Asteroid impact monitoring [PDF]

Serbian Astronomical Journal, 2006
Some asteroids and comets with Earth-crossing orbit may impact our planet, thus we need to be able to identify the cases which could have a dangerous close approach within a century.
Milani A.
doaj   +1 more source

Non-Cooperative LEO Satellite Orbit Determination Using Single Station for Space-Based Opportunistic Positioning

Remote Sensing
Space-based opportunistic positioning is a crucial component of resilient positioning, navigation, and timing (PNT) systems, and it requires the acquisition of orbit information for non-cooperative low Earth orbit (LEO) satellites.
Ruofan Deng, Honglei Qin, Yu Zhang
doaj   +1 more source

Space-Time Reference with an Optical Link

, 2015
We describe a method for realizing a high-performance Space-Time Reference (STR) using a stable atomic clock in a precisely defined orbit and synchronizing the orbiting clock to high-accuracy atomic clocks on the ground.
Berceau, Paul, Hollberg, Leo, Kahn, Joseph M., Taylor, Michael   +3 more
core   +1 more source

Orbit determination of space objects based on sparse optical data [PDF]

, 2010
While building up a catalog of Earth orbiting objects, if the available optical observations are sparse, not deliberate follow ups of specific objects, no orbit determination is possible without previous correlation of observations obtained at different ...
A. Milani, A. Rossi, Choc, D. Farnocchia, Farnocchia, G. Tommei, Gronchi, Jehn, Maruskin, Milani, Milani, Milani, Milani, Milani, Milani, Musci, R. Jehn, Rossi, Schildknecht, Schildknecht, Schildknecht, T. Schildknecht, Tommei, Valk, Vokrouhlický   +24 more
core   +2 more sources

Mechanisms and kinetic assays of aminoacyl‐tRNA synthetases

FEBS Letters, EarlyView.
Accurate protein synthesis is crucial for life. The key players are aminoacyl‐tRNA synthetases (AARSs), which read the genetic code by pairing cognate amino acids and tRNAs. AARSs establish high amino acid selectivity by employing physicochemical limits in molecular recognition.
Igor Zivkovic, Morana Dulic, Ita Gruic‐Sovulj   +2 more
wiley   +1 more source

Research on Sliding-Window Batch Processing Orbit Determination Algorithm for Satellite-to-Satellite Tracking

Aerospace
In response to the increasing demand for high-precision navigation of satellites operating in the cislunar space, this study introduces an onboard orbit determination algorithm considering both convergence and computational efficiency, referred to as the
Yingjie Xu, Xuan Feng, Shuanglin Li, Jinghui Pu, Shixu Chen, Wenbin Wang   +5 more
doaj   +1 more source

Precise Orbit Determination of FY-3C with Calibration of Orbit Biases in BeiDou GEO Satellites

Remote Sensing, 2018
The emerging BeiDou navigation satellite system has contributed to global precise positioning and has recently moved toward space-borne applications.
Qiang Zhang, Xiang Guo, Lizhong Qu, Qile Zhao   +3 more
doaj   +1 more source