Results 21 to 30 of about 3,949,170 (113)

A Stable H2O Atmosphere on Europa’s Trailing Hemisphere From HST Images

Geophysical Research Letters, 2021
Previous studies of the global intensities of the oxygen emissions at 1,356 Å and 1,304 Å revealed molecular oxygen (O2) in Europa's atmosphere. Here we investigate the relative changes of the two oxygen emissions when Europa emerges from eclipse as well
Lorenz Roth
doaj   +1 more source

PHANGS–JWST First Results: A Combined HST and JWST Analysis of the Nuclear Star Cluster in NGC 628

The Astrophysical Journal Letters, 2023
We combine archival Hubble Space Telescope and new James Webb Space Telescope imaging data covering the ultraviolet to mid-infrared regime to morphologically analyze the nuclear star cluster (NSC) of NGC 628, a grand-design spiral galaxy.
Nils Hoyer, Francesca Pinna, Albrecht W. H. Kamlah, Francisco Nogueras-Lara, Anja Feldmeier-Krause, Nadine Neumayer, Mattia C. Sormani, Médéric Boquien, Eric Emsellem, Anil C. Seth, Ralf S. Klessen, Thomas G. Williams, Eva Schinnerer, Ashley. T. Barnes, Adam K. Leroy, Silvia Bonoli, J. M. Diederik Kruijssen, Justus Neumann, Patricia Sánchez-Blázquez, Daniel A. Dale, Elizabeth J. Watkins, David A. Thilker, Erik Rosolowsky, Frank Bigiel, Kathryn Grasha, Oleg V. Egorov, Daizhong Liu, Karin M. Sandstrom, Kirsten L. Larson, Guillermo A. Blanc, Hamid Hassani   +30 more
doaj   +1 more source

Jovian Magnetospheric Injections Observed by the Hubble Space Telescope and Juno

Geophysical Research Letters, 2023
We compare Hubble Space Telescope observations of Jupiter's FUV auroras with contemporaneous conjugate Juno in situ observations in the equatorial middle magnetosphere of Jupiter.
J. D. Nichols, F. Allegrini, F. Bagenal, B. Bonfond, G. B. Clark, J. T. Clarke, J. E. P. Connerney, S. W. H. Cowley, R. W. Ebert, G. R. Gladstone, D. Grodent, D. K. Haggerty, B. Mauk, G. S. Orton, G. Provan, R. J. Wilson   +15 more
doaj   +1 more source

A 1.3% Distance to M33 from Hubble Space Telescope Cepheid Photometry

The Astrophysical Journal, 2023
We present a low-dispersion period–luminosity relation (PL) based on 154 Cepheids in Messier 33 (M33) with Hubble Space Telescope (HST) photometry from the PHATTER survey.
Louise Breuval, Adam G. Riess, Lucas M. Macri, Siyang Li, Wenlong Yuan, Stefano Casertano, Tarini Konchady, Boris Trahin, Meredith J. Durbin, Benjamin F. Williams   +9 more
doaj   +1 more source

Attitude Control and Parameter Optimization: A Study on Hubble Space Telescope

Measurement Science Review, 2023
In this work, we build a satellite attitude Proportional-Integral-Derivative (PID) controlled system by using the Hubble Space Telescope (HST) parameters as a reference and tune its controller parameters using various tuning methods.
Sayin Emre, Bitirgen Rahman, Bayezit Ismail   +2 more
doaj   +1 more source

Design and Preliminary Ground Experiment for Deployable Sunshade Structures of a Modular Space Telescope

Sensors
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
Ye Kuang, Shuaihui Wang, Yan Gao, Boqian Xu, Shuyan Xu   +4 more
doaj   +1 more source

PACMan2: Next Steps in Proposal Review Management

The Astronomical Journal, 2023
With the start of a new Great Observatories era, there is renewed concern that the demand for these forefront facilities, through proposal pressure, will exceed conventional peer-review management’s capacity for ensuring an unbiased and efficient ...
Louis-Gregory Strolger, Jamila Pegues, Tegan King, Nathan Miles, Michelle Ramsahoye, Keith Ceruti II, Brett Blacker, I. Neill Reid   +7 more
doaj   +1 more source

Saturn's equinoctial auroras [PDF]

, 2009
We present the first images of Saturn's conjugate equinoctial auroras, obtained in early 2009 using the Hubble Space Telescope. We show that the radius of the northern auroral oval is ∼1.5° smaller than the southern, indicating that Saturn's polar ...
Stallard, T. S., Badman, S. V., Crary, F. J., Wannawichian, S., Pryor, W. R., Mitchell, D. G., Gérard, J.-c., Grodent, D., Dougherty, M. K., Clarke, J. T., Cowley, S. W. H., Bunce, E. J., Kurth, W. S., Nichols, J. D., Talboys, D. L., Hansen, K. C.   +15 more
core   +3 more sources

A statistical analysis of the location and width of Saturn's southern auroras [PDF]

, 2006
A selection of twenty-two Hubble Space Telescope images of Saturn's ultraviolet auroras obtained during 1997–2004 has been analysed to determine the median location and width of the auroral oval, and their variability.
Badman, S. V., Cowley, S. W. H., Gérard, J.-c., Grodent, D.   +3 more
core   +6 more sources

Geometric Characterization of LEO–GEO Inter‐Satellite Links for Bidirectional Communications

International Journal of Satellite Communications and Networking, EarlyView.
ABSTRACT Incorporating geosynchronous Earth orbit (GEO) and low Earth orbit (LEO) satellites can extend communication services far beyond the reach of terrestrial infrastructure. A key enabler of such architectures is the establishment of inter‐satellite links (ISLs) between LEOs and GEOs to support bidirectional communications.
Muhammad Furqan, Lingfeng Ye, Yanming Feng   +2 more
wiley   +1 more source