Results 31 to 40 of about 1,065 (171)

ON THE PROGRAM AND PRELIMINARY RESULTS OF INVESTIGATIONS OF INTRADAY AND INTERDIURNAL FLUX VARIABILITY OF EXTRAGALACTIC RADIO SOURCES AT TELESCOPES OF VENTSPILS INTERNATIONAL RADIO ASTRONOMY CENTER (VIRAC)

Radio Physics and Radio Astronomy, 2017
Purpose: From April 2017, a monitoring program of observations has been started at the RT-16 telescope of Ventspils Radio Astronomy Center (frequencies 5, 6.1, 6.7, 8.4 GHz) to study the intraday and interdiurnal variability of extragalactic radio ...
A. L. Sukharev, V. V. Bezrukovs, M. Y. Bleiders, A. A. Orbidans, M. I. Ryabov   +4 more
doaj   +1 more source

An Outsider’s View of Extragalactic Infrared Astronomy [PDF]

Symposium - International Astronomical Union, 1981
No one could be more of an outsider to infrared astronomy than myself. Like all outsiders, one forms preconceived notions about disciplines outside one's own speciality. In my own case, I can summarise these under three headings.
openaire   +1 more source

Long-term future of extragalactic astronomy [PDF]

Physical Review D, 2002
If the current energy density of the universe is indeed dominated by a cosmological constant, then high-redshift sources will remain visible to us only until they reach some finite age in their rest-frame. The radiation emitted beyond that age will never reach us due to the acceleration of the cosmic expansion rate, and so we will never know what these
openaire   +4 more sources

Extragalactic stellar astronomy with the brightest stars in the universe [PDF]

Physica Scripta, 2007
AbstractA supergiants are objects in transition from the blue to the red (and vice versa) in the uppermost HRD. They are the intrinsically brightest “normal” stars at visual light with absolute visual magnitudes up to −9. They are ideal to study young stellar populations in galaxies beyond the Local Group to determine chemical composition and evolution,
Kudritzki, Rolf, Urbaneja, Miguel A., Bresolin, Fabio, Przybilla, Norbert   +3 more
openaire   +4 more sources

Highlights from the IceCube Neutrino Observatory [PDF]

EPJ Web of Conferences
The IceCube Neutrino Observatory has been collecting data for more than a decade. During this time, it has heralded the birth of neutrino astronomy with the discovery of the astrophysical neutrino flux.
Aguilar Juan A.
doaj   +1 more source

Ground‐Based Solar Radio Observations From the Mexican e‐Callisto Stations During the May 2024 Extreme Space Weather Events

Space Weather, Volume 24, Issue 8, August 2026.
Abstract The period from 1 to 14 May 2024 was marked by some of the most intense solar activity of Solar Cycle 25, including multiple X‐class flares, fast coronal mass ejections (CMEs), and diverse solar radio emissions. We present observations from the Mexican e‐Callisto network (REC‐Mx), including long‐duration continuum emissions (CTMs), Type II ...
E. Aguilar‐Rodriguez, G. Baron, R. Gutiérrez‐Zalapa, C. Y. Cruz‐Rodríguez, M. Rodriguez‐Martinez, M. A. Chacón, E. Romero‐Hernandez, K. S. Caballero‐Mora, J. Ramírez Vélez, E. Andrade‐Mascote, P. Villanueva‐Hernandez, I. A. Peralta‐Mendoza, J. Herrera, J. H. Castro‐Chacón, E. Perez‐Tijerina, J. A. Gonzalez‐Esparza, H. de León‐Hidalgo, R. Arceo‐Reyes, O. G. Morales‐Olivares, D. A. Garcia‐Sanchez, J. E. Perez‐Leon, C. Monstein, J. Bussons Gordo, M. Prieto Mateo   +23 more
wiley   +1 more source

Can Fractal Dimension Distinguish between Grand-design and Flocculent Spiral Arms?

The Astrophysical Journal
About two-thirds of disk galaxies host spiral arms, ranging from well-delineated grand-design spirals to fragmented flocculent spiral galaxies. We introduce fractal dimension D _B as a nonparametric measure to distinguish between grand-designs and ...
Biju Saha, Subhadip Dutta, Arunima Banerjee   +2 more
doaj   +1 more source

The Kinematic Bimodality: Efficient Feedback and Cold Gas Deficiency in Slow-rotating Galaxies

The Astrophysical Journal Letters, 2023
The bimodality in the stellar spin of low-redshift (massive) galaxies, ubiquitously existing at all star formation levels and in diverse environments, suggests that galaxies grow and quench through two diverged evolutionary pathways.
Bitao Wang, Yingjie Peng
doaj   +1 more source

Repeating Nuclear Transients From Repeating Partial Tidal Disruption Events

Astronomische Nachrichten, Volume 347, Issue 5, June 2026.
ABSTRACT Extragalactic nuclear transients that exhibit repeating outbursts can be modeled as the repeated dynamical interaction between bound stars and supermassive black holes (SMBHs). A subset of these transients, with recurrence timescales of months‐to‐years, have been explained as accretion flares from the repeated tidal stripping of a star by an ...
Ananya Bandopadhyay, Eric R. Coughlin, Julia Fancher, C. J. Nixon, Dheeraj R. Pasham   +4 more
wiley   +1 more source

On the Kinematic Nature of Apparent Disks at High Redshifts: Local Counterparts are Not Dominated by Ordered Rotation but by Tangentially Anisotropic Random Motion

The Astrophysical Journal Letters
It is not straightforward to physically interpret the apparent morphology of galaxies. Recent observations by the James Webb Space Telescope (JWST) revealed a dominant galaxy population at high redshifts ( z > 2) that were visually classified as disks ...
Bitao Wang, Yingjie Peng, Michele Cappellari, Hua Gao, Houjun Mo   +4 more
doaj   +1 more source