Results 11 to 20 of about 264 (177)
Decomposition of the central structure of NGC 2273 in the NIR: A case study
Astronomische Nachrichten, Volume 344, Issue 10, December 2023., 2023 Abstract The Seyfert 2 galaxy NGC 2273 is a prime target to explore how active nuclei can be fed. It has a star‐forming innermost nuclear ring with a radius of 0.33kpc from where material may be funneled to the supermassive black hole in its center. In this article, we discuss high‐resolution adaptive optics aided JHKs images of NGC 2273 taken with the
L. Schey +13 more
wiley +1 more source
Multiwavelength astrophysics of the blazar OJ 287 and the project MOMO
Astronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023 Abstract We are carrying out the densest and longest multiyear, multiwavelength monitoring project of OJ 287 ever done. The project MOMO (Multiwavelength Observations and Modeling of OJ 287) covers wavelengths from the radio to the high‐energy regime. A few selected observations are simultaneous with those of the Event Horizon Telescope (EHT).
S. Komossa +21 more
wiley +1 more source
Chemical abundances in the dwarf galaxy NGC 4163 based on the nebular and auroral emission lines
Astronomische Nachrichten, Volume 343, Issue 9-10, November-December 2022., 2022 Abstract We constructed an oxygen abundance map and N/O ratio map of the unusually low excitation dwarf irregular galaxy NGC 4163 based on publicly available spectroscopy obtained by the MaNGA survey. We detected auroral emission line [O II]λλ$$ \lambda \lambda $$7320,7330 which allows us to measure chemical abundance by direct Te$$ {\mathrm{T}}_e ...
I. A. Zinchenko, L. S. Pilyugin
wiley +1 more source
An investigation of open cluster Melotte 72 using Gaia DR2
Astronomische Nachrichten, Volume 342, Issue 4, Page 613-624, May 2021., 2021 Abstract The estimation of the main parameters of star clusters is significant in astrophysical studies. The most important aspect of using the Gaia DR2 survey lies in the positions, parallax, and proper motions of cluster stars with homogeneous photometry that make the membership probability determine with high accuracy.
Yasser Hendy, Ashraf Tadross
wiley +1 more source
1I/‘Oumuamua as an N2 Ice Fragment of an exo‐Pluto Surface: I. Size and Compositional Constraints
Journal of Geophysical Research: Planets, Volume 126, Issue 5, May 2021., 2021 Abstract The origin of the interstellar object 1I/‘Oumuamua has defied explanation. We perform calculations of the non‐gravitational acceleration that would be experienced by bodies composed of a range of different ices and demonstrate that a body composed of N2 ice would satisfy the available constraints on the non‐gravitational acceleration, size ...
Alan P. Jackson, Steven J. Desch
wiley +1 more source
X-ray absorption, interstellar reddening, and elemental abundances in the interstellar medium
Astrophysical Journal, 1975 J Audouze, C J Cesarsky
exaly +2 more sources
The Distribution of Interstellar Reddening Material
Astronomical Journal, 1968 exaly +2 more sources
The Astrophysical Journal, 1969 Interstellar reddening in solar vicinity, analyzing roles of galactic latitude and longitude and heliocentric ...
David M. Gottlieb, Walter L., II Upson
openaire +1 more source
The Shape of the Interstellar Reddening Curve [PDF]
International Astronomical Union Colloquium, 1965 When the Observed Spectral Intensity Distribution of an early-type star has been freed from the distortions caused by absorption in the Earth's atmosphere and by instrumental sensitivity factors, it is a measure of the true spectral intensity distribution of the star and of the modifications to that distribution caused by the interstellar material ...
A. B. Underhill, G. A. H. Walker
openaire +2 more sources
The Correlation of Interstellar Reddening and Lα Absorption [PDF]
Symposium - International Astronomical Union, 1973 For 61 stars whose interstellar Lα absorption was observed by OAO-2, the average relation of H I column density to B – V color excess is equal to 5 × 1021 atoms cm–2 mag–1. For a recent dust grain model this value implies that the density ratio 〈ρHI/ρdust〉 ≈ 100.
Edward B. Jenkins, Blair D. Savage
openaire +1 more source