Results 21 to 30 of about 33,443 (166)

Stellar Library of Differential Emission Measures and Extreme Ultraviolet Spectra: Dwarf Stars Observed by the Extreme Ultraviolet Explorer

The Astrophysical Journal
Extreme ultraviolet (EUV; 100–912 Å) photons influence the formation and evolution of planets by ionizing hydrogen and other species, but the EUV radiation of most exoplanet host stars is poorly constrained.
Girish M. Duvvuri, Zachory K. Berta-Thompson, J. Sebastian Pineda, Kevin France, Alexander Brown, Allison Youngblood, David J. Wilson, Cynthia S. Froning, P. Christian Schneider, Thomas Ayres, Keivan G. Stassun   +10 more
doaj   +1 more source

STRUCTURE OF VARIABILITY INDEXES OF COSMIC WEATHER AS APPLIED TO DATA MONITORING OF FLUXES OF RADIO SOURCES AT THE “URAN-4” RADIO TELESCOPE

Radio Physics and Radio Astronomy, 2017
Purpose: Investigation of the effects of the influence of solar and geomagnetic activity on the state of the Earth’s upper atmosphere by the method of “transmission through” it with the radiation of cosmic radio sources.
L. I. Sobitniak, M. I. Ryabov, A. L. Sukharev, S. K. Panishko   +3 more
doaj   +1 more source

Spectroradiometry with Space Telescopes

, 2016
Radiometry has been of fundamental importance in astronomy from the early beginnings. In this review, we provide an overview of how to achieve a valid laboratory calibration of space telescopes and discuss ways to reliably extend this calibration to the ...
Colina, Luis, Huber, Martin C. E., Pauluhn, Anuschka, Smith, Peter L.   +3 more
core   +1 more source

Gravitational lensing reveals ionizing ultraviolet photons escaping from a distant galaxy [PDF]

, 2019
During the epoch of reionisation, neutral gas in the early Universe was ionized by hard ultraviolet radiation emitted by young stars in the first galaxies. To do so, ionizing ultraviolet photons must escape from the host galaxy.
Bayliss, Matthew, Chisholm, John, Dahle, Håkon, Florian, Michael K., Gladders, Michael D., Gronke, Max, Mahler, Guillaume, Rigby, Jane R., Rivera-Thorsen, T. Emil, Sharon, Keren   +9 more
core   +1 more source

Photocatalytic Water Splitting on the Lunar Surface: Prospects for In Situ Resource Utilization

Advanced Materials Interfaces, EarlyView.
Water has been found in craters on the moon nearby locations which are illuminated >80% of the time. Photocatalysis uses energy from sunlight to drive chemical reactions such as water splitting to produce oxygen and hydrogen. It is a scalable technology that requires lighter equipment and utilizes resources available on the moon. ABSTRACT The discovery
Ranjani Kalyan, Thomas D. Small, Gregory F. Metha, Mahmoud Adel Hamza, Thomas J. O'Dea, Yideng Shen, Cameron J. Shearer   +6 more
wiley   +1 more source

Toward a 2D H I Map of the Local Interstellar Medium

The Astronomical Journal
Obtaining a complete census of gas in the local interstellar medium (LISM;
Allison Youngblood, Kevin France, Tommi Koskinen, James Paul Mason, Seth Redfield, Brian E. Wood, Vincent Bourrier, Leonardo dos Santos, Christopher Johns-Krull, George W. King, Jeffrey L. Linsky, Sarah Peacock   +11 more
doaj   +1 more source

The Interstellar Medium In Galaxies Seen A Billion Years After The Big Bang [PDF]

, 2015
Evolution in the measured rest frame ultraviolet spectral slope and ultraviolet to optical flux ratios indicate a rapid evolution in the dust obscuration of galaxies during the first 3 billion years of cosmic time (z>4).
A Leauthaud, A. Karim, AB Rogers, AE Shapley, AM Koekemoer, C Leitherer, C Leitherer, C. Carilli, C. M. Carollo, C. M. Casey, CL Carilli, CL Steinhardt, CM Casey, CM Casey, D Schaerer, D Watson, D. Riechers, DA Riechers, FP Israel, G Bruzual, G Hinshaw, G. Jones, GR Meurer, I De Looze, JS Speagle, K Ota, K. Sheth, KD Gordon, L. Yan, M Boquien, M Ouchi, M Pettini, N Reddy, N Scoville, N. Scoville, NA Reddy, NM Förster Schreiber, O Ilbert, O. Ilbert, O. LeFevre, P Madau, P. L. Capak, PL Capak, R Wang, RJ Bouwens, RJ Bouwens, S Charlot, S Malhotra, S. Lilly, SL Finkelstein, T Díaz-Santos, T Díaz-Santos, V Buat, V. Smolcic, X Kong   +54 more
core   +4 more sources

Study of Free‐Space Optical Quantum Network: Review and Prospectives

Advanced Science, EarlyView.
Free from the constraints of fiber connections, free‐space quantum network enables longer and more flexible quantum network connections. This review summarizes and comparatively analyzes free‐space quantum network experiments based on ground stations, satellites, and mobile platforms.
Hua‐Ying Liu, Zhenda Xie, Shining Zhu
wiley   +1 more source

Coronal Magnetometry with EUV Permitted Lines

The Astrophysical Journal
A major challenge in solar physics is to obtain empirical information on the magnetic field of the million-degree plasma of the solar corona. To this end, we need observables of the solar radiation sensitive to the coronal magnetic field.
Nataliia G. Shchukina, Javier Trujillo Bueno, Supriya Hebbur Dayananda, Rafael Manso Sainz, Andrii V. Sukhorukov   +4 more
doaj   +1 more source

On the Nature of Soft X-ray Weak Quasi-Stellar Objects [PDF]

, 1999
Recent studies of QSOs with ROSAT suggest the existence of a significant population of Soft X-ray Weak QSOs (SXW QSOs) where the soft X-ray flux is ~ 10-30 times smaller than in typical QSOs.
A. Laor, Beverley J. Wills, Boller Th., Boller Th., Brinkmann W., Brosch N., Clavel J., Hartigan J. A., Hes R., Lawrence A., Miller P., Rachen J. P., Serego Alighieri S., Ulrich M.-H., W. N. Brandt, Wills B. J., Yuan W.   +16 more
core   +3 more sources