A5065112667- Astro and Planetary Science
- Gamma-ray bursts and supernovae
- SAS software applications and methods
- Planetary Science and Exploration
- Isotope Analysis in Ecology
- Stellar, planetary, and galactic studies
- Astronomical Observations and Instrumentation
- Nuclear Physics and Applications
- Solar and Space Plasma Dynamics
- Space Exploration and Technology
- Astrophysics and Star Formation Studies
- Astronomy and Astrophysical Research
- Astrophysics and Cosmic Phenomena
- Atmospheric Ozone and Climate
- Astrophysical Phenomena and Observations
- Space Science and Extraterrestrial Life
- Geophysics and Gravity Measurements
- Geology and Paleoclimatology Research
- Atmospheric and Environmental Gas Dynamics
- Geomagnetism and Paleomagnetism Studies
- Particle Accelerators and Free-Electron Lasers
- Geological and Geochemical Analysis
- Phenothiazines and Benzothiazines Synthesis and Activities
- Advanced Data Storage Technologies
- Astronomical and nuclear sciences
Institute of Astronomy and National Astronomical Observatory
2015-2024
Armagh Observatory & Planetarium
2015-2024
Bulgarian Academy of Sciences
2008-2010
After several years of quiescence, the blazar CTA 102 underwent an exceptional outburst in 2012 September–October. The flare was tracked from γ-ray to near-infrared (NIR) frequencies, including Fermi and Swift data as well photometric polarimetric observatories. An intensive Glast-Agile support programme Whole Earth Blazar Telescope (GASP–WEBT) collaboration campaign optical NIR bands, with addition previously unpublished archival extension through fall 2015, allows comparison this previous...
Near Earth Asteroids are of great interest to the scientific community due their proximity Earth, making them both potential hazards and possible targets for future missions, as they relatively easy reach by spacecraft. A number techniques models can be used constrain physical parameters build a comprehensive assessment these objects. In this work, we compare property results obtained from improved $H_V$ absolute magnitude values, thermophysical modeling, polarimetry data well-known...
Abstract Near-Earth asteroids are of great interest to the scientific community due their proximity Earth, making them both potential hazards and possible targets for future missions, as they relatively easy reach by spacecraft. A number techniques models can be used constrain physical parameters build a comprehensive assessment these objects. In this work, we compare property results obtained from improved H V absolute magnitude values, thermophysical modeling, polarimetry data well-known...
Abstract In 2018, the near-Earth object (155140) 2005 UD (hereafter UD) experienced a close fly by of Earth. We present results from an observational campaign involving photometric, spectroscopic, and polarimetric observations carried out across wide range phase angles (0.°7–88°). also analyze archival NEOWISE observations. report absolute magnitude H V = 17.51 ± 0.02 mag albedo p 0.10 0.02. has been dynamically linked to Phaethon due their similar orbital configurations. Assuming surface...
ABSTRACT Comet 67P/Churyumov–Gerasimenko (67P) become observable for the first time in 2021 since Rosetta rendezvous 2014–2016. Here, we present pre-perihelion polarimetric measurements of 67P from performed with Very Large Telescope (VLT), as well post-perihelion 2015 to 2016 obtained VLT and William Herschel Telescope. This new data covers a phase angle range ∼4○−50○ presents unprecedentedly high S/N ratio. Complementing previous measurements, curve resembles that other Jupiter family...
A multi-colour phase-polarization curve of asteroid (3200)~Phaethon has been obtained during the December 2017 apparition by merging measurements taken at observing station Calern (France) and Rhozen observatory (Bulgaria). All observations were in positive polarization branch, phase angle ranging from 36$^\circ$ to 116$^\circ$. The measured values linear are among highest ever observed for a Solar system body. covered interval was not sufficiently extended derive firm determination $P_{\rm...
We present a summary of the campaign remote observations that supported European Space Agency's Rosetta mission. Telescopes across globe (and in space) followed comet 67P/Churyumov-Gerasimenko from before Rosetta's arrival until nearly end mission September 2016. These provided essential data for planning, large-scale context information coma and tails beyond spacecraft, way to directly compare 67P with other comets. The revealed be relatively `well behaved' comet, typical Jupiter family...
Asteroid (3200) Phaethon is a Near-Earth Apollo asteroid with an unusual orbit that brings it closer to the Sun than any other known asteroid. Its last close approach Earth was in mid-December 2017 and next one will be on October 2026. Previous rotationally time-resolved spectroscopy of showed its spectral slope slightly bluish, agreement B/F taxonomic classification, but at some rotational phases, changes reddish. Motivated by this result we performed imaging polarimetry during recent...
So far, only two interstellar objects have been observed within our Solar System. While the first one, 1I/'Oumuamua, had asteroidal characteristics, second 2I/Borisov, showed clear evidence of cometary activity. We performed polarimetric observations comet 2I/Borisov using European Southern Observatory Very Large Telescope to derive physical characteristics its coma dust particles. Here we show that polarization is higher than what typically measured for System comets. This feature...
ABSTRACT In 2018 December, the main-belt asteroid (6478) Gault was reported to display activity. is an belonging Phocaea dynamical family and not previously known be active, nor any other member of family. this work, we present results photometric spectroscopic observations that commenced soon after discovery We obtained over two apparitions monitor its activity, rotation period, composition, possible non-gravitational orbital evolution. find has a period P = 2.4929 ± 0.0003 h with...
We have used the XSHOOTER echelle spectrograph on European South Observatory (ESO) Very Large Telescope (VLT) to obtain UVB-VIS-NIR (ultraviolet-blue (UVB), visible (VIS) and near-infrared (NIR)) reflectance spectra of two members Eureka family L5 Mars Trojans in order test a genetic relationship Eureka.In addition obtaining spectra, we also carried out VRI photometry one VLT targets using 2-m telescope at Bulgarian National Astronomical -Rozhen two-channel focal reducer.We found that these...
Context. Polarimetry is a powerful remote sensing tool to characterise solar system planets and, potentially, detect and exoplanets. The linear polarisation of planet as function wavelength phase angle sensitive the cloud haze particle properties in planetary atmospheres, well their altitudes optical thicknesses.
In late 2010 a Jupiter Family comet 103P/Hartley 2 was subject of an intensive world-wide investigation. On UT October 20.7 the approached Earth within only 0.12 AU, and on November 4.6 it visited by NASA's EPOXI spacecraft. We joined this international effort organized observing campaign. The images were obtained through narrowband filters using 2-m telescope Rozhen National Astronomical Observatory. They taken during 4 nights around moment encounter. Image processing methods periodicity...
Context.The Jupiter family comet 73P/Schwassmann-Wachmann 3 (SW3) split into several pieces in 1995. Some of the original fragments were observed during next apparition 1999-2001. The last return 2005-2006 was accompanied by tremendous further splitting some SW3 components – particular component B a large number subfragments.
Context. Trojan asteroids orbit in the Lagrange points of system Sun-planet-asteroid. Their dynamical stability make their physical properties important proxies for early evolution our solar system.
We present preliminary results of the narrow-band CN observations comet 8P/Tuttle from early January 2008, realized as part a project consisting near-simultaneous spectroscopic monitoring HCN at millimeter-wavelengths and optical imaging coma. The mean-image subtraction method revealed low-contrast envelopes. Using image cross-correlation technique we measured projected velocity these shells. For sunward found it to be equal 0.96 ± 0.03 km s−1 on 4 1.10 0.01 9, whereas anti-sunward reached...