Results 21 to 30 of about 52,995 (203)

Interstellar reddening in the galaxy [PDF]

open access: yes, 1964
Objective prism spectra obtained with the 16/24/60-inch Schmidt telescope have been used for an investigation of the wavelength dependence of interstellar absorption in the spectral range from 8000A to 3450A, in a region of 30 square degrees in ...
Nandy, Kashi Nath
core   +3 more sources

Decomposition of the central structure of NGC 2273 in the NIR: A case study

open access: yesAstronomische 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

open access: yesAstronomische 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

open access: yesAstronomische 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

open access: yesAstronomische 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

open access: yesJournal 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

Turbulence in the interstellar medium [PDF]

open access: yes, 2014
Turbulence is ubiquitous in the insterstellar medium and plays a major role in several processes such as the formation of dense structures and stars, the stability of molecular clouds, the amplification of magnetic fields, and the re-acceleration and ...
Chian, A. C. -L.   +9 more
core   +2 more sources

Technology requirements of exploration beyond Neptune by solar sail propulsion [PDF]

open access: yes, 2010
This paper provides a set of requirements for the technology development of a solar sail propelled Interstellar Heliopause Probe mission. The mission is placed in the context of other outer solar systems missions, ranging from a Kuiper Belt mission ...
Hughes, G.W.   +2 more
core   +4 more sources

PLATO as it is: A legacy mission for Galactic archaeology

open access: yesAstronomische Nachrichten, Volume 338, Issue 6, Page 644-661, July 2017., 2017
Deciphering the assembly history of the Milky Way is a formidable task, which becomes possible only if one can produce high‐resolution chrono‐chemo‐kinematical maps of the Galaxy. Data from large‐scale astrometric and spectroscopic surveys will soon provide us with a well‐defined view of the current chemo‐kinematical structure of the Milky Way, but it ...
A. Miglio   +104 more
wiley   +1 more source

Home - About - Disclaimer - Privacy