Search Publications
Membership and fundamental parameters of the intermediate-age open clusters NGC 2281 and NGC 2539 based on Gaia-DR2
Gao, Xin-Hua
This paper presents an investigation on the two intermediate-age open clusters NGC 2281 and NGC 2539 based on Gaia Data Release 2 (Gaia-DR2). A combined machine-learning method is used to identify likely cluster members of the two clusters, taking into account the astrometric and photometric data of Gaia-DR2. It is found that NGC 2281 and NGC 2539…
A catalogue of 108 extended planetary nebulae observed by GALEX
Pradhan, Ananta C.; Panda, Swayamtrupta; Ojha, Devendra K. +2 more
We present the ultraviolet (UV) imaging observation of planetary nebulae (PNe) using archival data of Galaxy Evolution Explorer (GALEX). We found 358 PNe detected by GALEX in near-UV (NUV). We have compiled a catalogue of 108 extended PNe with sizes greater than
Dust-ion-acoustic modes at comet 67P/Churyumov-Gerasimenko
Chen, Hui; Yang, Weiheng; Liu, Sanqiu
The dynamics of dust-ion-acoustic (DIA) modes at Comet 67P/Churyumov-Gerasimenko, where H2O+ ions with warm and cold electrons as well as dust grains were detected, are investigated within the two-electron-temperature dusty plasmas model by the kinetic theory. In terms of current-driven DIA waves, the bulk electron drift is a…
Hunting Young White Dwarfs at the Center of Planetary Nebulae
Weidmann, Walter A.; Ahumada, Javier A.; Miller Bertolami, Marcelo M. +1 more
We present Gemini-South observations of nine faint and extended planetary nebulae (PNe). Using direct images taken with the spectrograph Gemini-South multi-object spectrograph (GMOS), we built the (u\prime -g\prime ) versus (g\prime -r\prime ) diagrams of the stars in the observed areas which allowed us …
Galactic archaeology with Gaia
Wyse, Rosemary
The past and present merger activity of the Milky Way galaxy has recently been put into sharp focus through the analysis of data from the Gaia astrometric satellite. These data were released by the European Space Agency in 2016 (DR1) and 2018 (DR2). The emerging picture created is one of persistent disequilibrium, with high merger activity some 10…
Revealing the nature of central emission nebulae in the dwarf galaxy NGC 185
Ilić, D.; Vučetić, M. M.; Onić, D. +6 more
Aims: In this paper we present new optical observations of the galaxy NGC 185 intended to reveal the status of supernova remnants (SNRs) in this dwarf companion of the Andromeda galaxy. Previously, it was reported that this galaxy hosts one SNR.
Methods: Our deep photometric study with the 2m telescope at Rozhen National Astronomical Obs…
Cosmic biology in perspective
Wickramasinghe, N. C.; Lattanzio, John C.; Tout, Christopher A. +2 more
A series of astronomical observations obtained over the period 1986 to 2018 supports the idea that life is a cosmic rather than a purely terrestrial or planetary phenomenon. These include (1) the detection of biologically relevant molecules in interstellar clouds and in comets, (2) mid-infrared spectra of interstellar grains and the dust from come…
GUMICS-4 analysis of interplanetary coronal mass ejection impact on Earth during low and typical Mach number solar winds
Pulkkinen, Tuija I.; Raukunen, Osku; Dimmock, Andrew P. +5 more
We study the response of the Earth's magnetosphere to fluctuating solar wind conditions during interplanetary coronal mass ejections (ICMEs) using the Grand Unified Magnetosphere-Ionosphere Coupling Simulation (GUMICS-4). The two ICME events occurred on 15-16 July 2012 and 29-30 April 2014. During the strong 2012 event, the solar wind upstream val…
High-frequency dynamics of an active region moss as observed by IRIS
Van Doorsselaere, Tom; Pant, Vaibhav; Banerjee, Dipankar +1 more
The high temporal, spatial and spectral resolution of Interface Region Imaging Spectrograph (IRIS) has provided new insights into the understanding of different small-scale processes occurring at the chromospheric and transition region (TR) heights. We study the dynamics of high-frequency oscillations of an active region (AR 2376) moss as recorded…
AKARI mission program: Excavating Mass Loss History in extended dust shells of Evolved Stars (MLHES). I. Far-IR photometry†
Yamamura, Issei; Takita, Satoshi; Izumiura, Hideyuki +3 more
We performed a far-IR imaging survey of the circumstellar dust shells of 144 evolved stars as a mission program of the AKARI infrared astronomical satellite using the Far-Infrared Surveyor (FIS) instrument. With this survey, we deliver far-IR surface brightness distributions of roughly 10' × 40' or 10' × 20' areas of the sky around the target evol…