Related papers: Arthur Neville Brown: schoolmaster and variable st…
It is argued that an important fraction of PNe present large temperature variations that are not due to observational errors nor to incomplete atomic physics. Seven possible causes for these variations are reviewed, one of them is presented…
C.V. Raman (1888 - 1970) was a creative scientist, enthusiastic teacher and a science celebrity in India. In all these roles, he communicated science effectively. In this essay, I ask how and why did he communicate science. I take a few…
Pulsational variability is observed in several types of main sequence stars with anomalous chemical abundances. In this contribution I summarize the relationship between pulsations and chemical peculiarities, giving special emphasis to…
The Fourier spectral techniques that are common in Astronomy for analyzing periodic or multi-periodic light-curves lose their usefulness when they are applied to unsteady light-curves. We review some of the novel techniques that have been…
Long-period variables are bright, evolved red giant stars showing periodic photometric changes due to stellar pulsation. They follow one or more period-luminosity and period-age relations, which make them highly promising distance…
Narayan Chandra Rana, a person with extraordinary potential from a remote village of Bengal, India, came into the limelight of the international scientific world through his exceptional talent, zeal and courage. In his very short life-span,…
The time-variable electromagnetic sky has been well-explored at a wide range of wavelengths. Numerous high-energy space missions take advantage of the dark Gamma-ray and X-ray sky and utilize very wide field detectors to provide almost…
The central star of the planetary nebula PRTM 1 (PN G243.8-37.1) was previously found to be variable by M. Pena and colleagues. As part of a larger programme aimed towards finding post common-envelope binary central stars we have monitored…
We have conducted a long-term V-band photometric monitoring of M33 on 95 nights during four observing seasons (2000 - 2003). A total number of 6418 lightcurves of bright objects in the range of 14 - 21 mag have been obtained. All…
Intensive monitoring of low-extinction windows towards the galactic bulge has provided in the last years valuable information for studies about the dynamics, kinematics and formation history of this part of the galaxy, mainly by…
This paper contains the fifth part of the Catalog of Variable Stars created from the V-band photometric data collected by 9x9 deg camera of the All Sky Automated Survey. Preliminary list of variable stars found in the fields located between…
We present a new catalogue of variable stars compiled from data taken for the University of New South Wales Extrasolar Planet Search. From 2004 October to 2007 May, 25 target fields were each observed for 1-4 months, resulting in ~87000…
Strongly magnetized, accreting neutron stars show periodic and aperiodic variability over a wide range of time scales. By obtaining spectral and timing information on these different time scales, we can have a closer look into the physics…
We consider the infrared factorisation of non-abelian multi-particle scattering amplitudes, and we study the form of the universal colour operator responsible for infrared divergences, when expressed in terms of coordinates on the…
Cataclysmic variables are among the photometrically most unstable stars in the zoo of stellar objects, exhibiting light variations on all time-scales between millennia and seconds. The literature is full of reports on variable phenomena…
The 2025 UK National Astronomy Meeting (NAM) in Durham played host to a session titled "Unseen Astronomy", involving a variety of astronomy researchers in diverse fields. This unique meeting focussed on a number of novel projects exploring…
Stars like company. They are mostly formed in clusters and their lives are often altered by the presence of one or more companions. Interaction processes between components may lead to complex outcomes like Algols, blue stragglers,…
We study in depth a certain permutation statistic that was the subject of a brilliant insight by 12-year-old Noga Alon. Our approach is purely empirical and experimental, yet it is fully rigorous, thereby debunking, yet another time, the…
We present more than 80 new variable stars discovered during the first observing season of the APACHE survey. APACHE is a project aimed at detecting extrasolar planets transiting nearby, bright M dwarfs by using an array of small-aperture…
This paper continues the cycle of authors' works on the detection of precursors of large flares (M5 and higher classes) in active regions (ARs) of the Sun by their microwave radiation and magnetographic characteristics. Generalization of…