Results 51 to 60 of about 411,045 (265)
Ritchey-Chretien Telescope [PDF]
, 1973 A Ritchey-Chretien telescope is described which was designed to respond to images located off the optical axis by using two transparent flat plates positioned in the ray path of the image.
Amon, M., Rosin, S.
core +1 more source
, 2014 Present telescopes and future extremely large telescopes make use of fiber-fed spectrographs to observe at optical and infrared wavelengths. The use of fibers largely simplifies the interfacing of the spectrograph to the telescope.
Iuzzolino, M. +4 more
core +1 more source
Multi-wavelength visibility measurements of the red giant R Doradus [PDF]
, 2000 We present visibility measurements of the nearby Mira-like star R Doradus taken over a wide range of wavelengths (650--990 nm). The observations were made using MAPPIT (Masked APerture-Plane Interference Telescope), an interferometer operating at the 3.9-
Barton, J. R. +6 more
core +2 more sources
Solid Harmonic Wavelet Bispectrum for Image Analysis
Advanced Science, EarlyView.The Solid Harmonic Wavelet Bispectrum (SHWB), a rotation‐ and translation‐invariant descriptor that captures higher‐order (phase) correlations in signals, is introduced. Combining wavelet scattering, bispectral analysis, and group theory, SHWB achieves interpretable, data‐efficient representations and demonstrates competitive performance across texture,
Alex Brown +3 more
wiley +1 more source
Implementing of the ISON project in Northern Mexico
Open Astronomy, 2018 ISON, being an open international project that collects and interprets data about space objects for scientific analysis and spacecraft operators, includes about 40 observational sites.
Mokhnatkin Artem +5 more
doaj +1 more source
Structure of distributed control system in Seimei telescope
SICE Journal of Control, Measurement, and System Integration, 2021 A segmented mirror control system is indispensable for operating an astronomical telescope which is equipped with a segmented primary mirror. In this study, we focus on the distributed control system (DCS) proposed for Seimei telescope.
Ichiro Jikuya +4 more
doaj +1 more source
Long-Term Trends of Astroclimatic Parameters above the Terskol Observatory
Atmosphere, 2023 Astroclimatic conditions characterize the quality of an astronomical site. The Terskol Observatory was founded over 42 years ago in 1980. The astronomical site (coordinates 43°16′29″ N, 42°30′03″ E) is located about 10 km from Mt.
Lidia A. Bolbasova, Evgeniy A. Kopylov
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Advanced Science, EarlyView.Inspired by nature's competitive maneuvers, this study introduces a combustion‐driven soft actuator that powers a multi‐modal “Jump‐and‐Fly Catbot” (JFC). With millisecond response, high‐force output (over 70 times its weight) and precise control (error within 5%), the robot can jump, fly, hover, and escape from challenging environments, achieving ...
Hongkuan Ma +4 more
wiley +1 more source
The Influence of On-Orbit Micro-Vibration on Space Gravitational Wave Detection
Photonics, 2023 Large-aperture space telescopes have played an important role in space gravitational wave detection missions. Overcoming the influence of the space environment on interstellar laser distance measurement and realistic high-concentration laser distance ...
Zhiwei Chen +4 more
doaj +1 more source
Advanced Science, EarlyView.A large‐aperture, high focusing efficiency and polarization‐independent THz single‐layer achromatic metalens is reported via discrete multi‐wavelength achromatic design and global optimization algorithm. The fabricated metalens exhibits a largest diameter of 2.21 cm, excellent achromatic performance, extremely high average focusing efficiency (> 46 ...
Xiaoqiang Jiang +6 more
wiley +1 more source