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On-orbit assembling space telescope (OAST) is one of the most feasible methods to implement a large-scale space telescope. Unlike a monolithic space telescope (such as Hubble Space Telescope, HST) or a deployable space telescope (such as James Webb Space Telescope, JWST), OAST can be assembled in the spatial environment. To ensure proper telescope performance, OAST must be equipped with a large deployable sunshade. In order to verify the technology of the OAST, the authors propose a modular space telescope on the China Space Station (CSS) and design a deployable sunshade. The deployable mechanism of the sunshade is made up of a radial deployable mechanism and an axial deployable mechanism. The paper describes the overall design approach, the key component technologies, and the design and preliminary testing of a part of the deployable sunshade assembly.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11014395 | PMC |
http://dx.doi.org/10.3390/s24072280 | DOI Listing |
Chem Sci
September 2025
Department of Chemistry, University of Hawai'i at Manoa Honolulu HI 96822 USA
By connecting laboratory dynamics with cosmic observables, this work highlights the critical role of reactions between highly reactive species in shaping the molecular inventory of the interstellar medium and opens new windows into the spectroscopically elusive corners of astrochemical complexity. The gas phase formation of distinct CH isomers is explored through the bimolecular reaction of tricarbon (C, XΣ ) with the vinyl radical (CH, XA') at a collision energy of 44 ± 1 kJ mol employing the crossed molecular beam technique augmented by electronic structure and Rice-Ramsperger-Kassel-Marcus (RRKM) calculations. This barrierless and exoergic reaction follows indirect dynamics and is initiated by the addition of tricarbon to the radical center of the vinyl radical forming a symmetric doublet collisional complex (CCCCHCH).
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
September 2025
Department of Chemistry, University of Copenhagen, Universitetsparken 5, Copenhagen-Ø, DK-2100, Denmark. Electronic address:
Absorption spectra of neopentyl alcohol and pinacolyl alcohol are recorded in the gas phase at room temperature and equilibrium conditions. A combination of conventional Fourier transform spectroscopy and cavity ringdown spectroscopy is used to cover the spectral OH-stretching regions, Δv=1-5. The conformer distributions of the alcohols are determined from the recorded spectra combined with transition intensities calculated with a reduced dimensional local mode model.
View Article and Find Full Text PDFACS Earth Space Chem
August 2025
Laboratory for Astrophysics, Leiden Observatory, Leiden University, P.O. Box 9513, Leiden 2300 RA, The Netherlands.
Carbonyl sulfide (OCS) is currently the only securely detected sulfur-bearing species in interstellar ices, making it an ideal window into solid-state sulfur chemistry in dense star-forming regions. Previous astronomical observations of the OCS asymmetric stretching mode (ν) at ∼2040 cm (∼4.9 μm) demonstrate that interstellar OCS may be embedded in CHOH-rich ices, indicating that OCS likely forms in the coldest, densest parts of star-forming regions where catastrophic CO freezeout occurs.
View Article and Find Full Text PDFWe report on the 2024 September 9 sustained gamma-ray emission (SGRE) event observed by the Large Area Telescope (LAT) on board the Fermi satellite. The hevent was associated with a backside solar eruption observed by multiple spacecraft such as the Solar and Heliospheric Observatory (SOHO), Solar Terrestrial Relations Observatory (STEREO), Parker Solar Probe (PSP), Solar Orbiter (SolO), Solar Dynamics Observatory (SDO), Wind, and GOES, and by ground-based radio telescopes. Fermi/LAT observed the SGRE after the EUV wave from the backside eruption crossed the limb to the frontside of the Sun.
View Article and Find Full Text PDFACS Earth Space Chem
August 2025
Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States.
The evolution of interstellar ices can be studied with thermal tracers such as the vibrational modes of CO ice that show great diversity depending on their local chemical and thermal environment. Now with the wide spectral coverage and sensitivity of the James Webb Space Telescope we can obtain observations of the weak and strong CO absorption features inhabiting the near- and mid-infrared spectral region. In this work we present observations of the 15.
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