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Changing-look active galactic nuclei
Nature Astronomy, 2022This article reviews the developments on the topic of so-called changing-look active galactic nuclei from the past ten years or so. These active galactic nuclei show dramatic flux and spectral changes at X-ray, ultraviolet and optical wavelengths, due to
C. Ricci, B. Trakhtenbrot
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Galactic ultraviolet astronomy
Reports on Progress in Physics, 1987A general presentation of astrophysical observations in the ultraviolet is given. First the particular nature of ultraviolet studies is emphasises. This is followed by a brief historical presentation of some of the typical instrumentation used. Then, in the framework of galactic observations, some of the most important results obtained concerning the ...
A Vadal-Madjar +5 more
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Publications of the Astronomical Society of Australia, 1971
Until the last six years few infrared observations of astronomical objects (other than the Sun and planets) had been attempted. Those few were primarily concerned with obtaining bolometric corrections and effective temperatures, the variation of bolometric magnitudes of late-type variables, and the derivation of the laws of interstellar extinction.
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Until the last six years few infrared observations of astronomical objects (other than the Sun and planets) had been attempted. Those few were primarily concerned with obtaining bolometric corrections and effective temperatures, the variation of bolometric magnitudes of late-type variables, and the derivation of the laws of interstellar extinction.
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Active galactic nuclei: what’s in a name?
The Astronomy and Astrophysics Review, 2017Active galactic nuclei (AGN) are energetic astrophysical sources powered by accretion onto supermassive black holes in galaxies, and present unique observational signatures that cover the full electromagnetic spectrum over more than twenty orders of ...
P. Padovani +10 more
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Galactic Neutrinos and uv Astronomy
Physical Review Letters, 1980Slowly moving massive neutrinos may be responsible for the invisible mass in galactic halos and the missing mass of the universe. Massive neutrinos are expected to decay into lighter neutrinos and uv photons, with lifetimes long on the Hubble scale. The possible detection of these neutrino-decay photons is discussed.
A. De Rújula, S. L. Glashow
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Astronomy & Astrophysics
We aim to accurately measure the dynamical mass and distance of Cepheids by combining radial velocity measurements with interferometric observations. Cepheid mass measurements are particularly necessary for solving the Cepheid mass discrepancy, while ...
A. Gallenne +25 more
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We aim to accurately measure the dynamical mass and distance of Cepheids by combining radial velocity measurements with interferometric observations. Cepheid mass measurements are particularly necessary for solving the Cepheid mass discrepancy, while ...
A. Gallenne +25 more
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Astronomy. Galactic encounters.
Science (New York, N.Y.), 2003Studies of the Local Group of galaxies to which the Milky Way belongs are shedding light on some of the processes by which galaxies formed and evolved. In her Perspective, Wyse reviews recent studies of collisions between the Milky Way and smaller satellite galaxies.
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Kapteyn and Galactic Astronomy Around 1920
2020Throughout his life, Oort has testified in spoken word and in writing of his great admiration for the scientific approach and work of Kapteyn and his personality, which inspired him to become an astronomer. In order to consider Oort’s student time in Groningen, I must first describe Kapteyn’s person and his work.
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