Related papers: Disintegration of Active Asteroid P/2016 G1 (PANST…
We present pre-perihelion infrared 8 to 31 micron spectrophotometric and imaging observations of comet C/2012 K1 (Pan-STARRS), a dynamically new Oort Cloud comet, conducted with NASA's Stratospheric Observatory for Infrared Astronomy…
C/2017 K2 (PANSTARRS) is an Oort cloud comet previously observed to be active at heliocentric distances r>20 au on what is likely its first passage through the inner solar system. We observed the comet on 2021 March 19-20 at r=6.82 au…
We analysed the centre of NGC 1566, which hosts a well-studied active galactic nucleus (AGN), known for its variability. With the aid of techniques such as Principal Component Analysis Tomography, analysis of the emission-line spectra,…
Optical observations of the Oort cloud comet C/2017 K2 (PANSTARRS) show that its activity began at large heliocentric distances (up to 35 au), which cannot be explained by either the sublimation or the crystallization of water ice.…
In this paper, we present a detailed analysis of a potential asteroid candidate, ISP0010, using images provided by the Pan-STARRS 1 telescope as part of our participation in the International Astronomical Search Collaboration campaign. IASC…
We describe observations and physical characteristics of Earth-crossing asteroid 2024 YR$_4$, discovered on 2024 December 27 by the Asteroid Terrestrial-impact Last Alert System. The asteroid has semi-major axis, $a$ = 2.52 au,…
Mitigation of the threat from airbursting asteroids requires an understanding of the potential risk they pose for the ground. How asteroids release their kinetic energy in the atmosphere is not well understood due to the rarity of…
We have used the Owens Valley Radio Observatory Millimeter Array to obtain a map of the J = (1-0) CO emission from the circumstellar shell around HD 179821, a highly evolved G-type star which will probably explode as a supernova in the next…
RZ Piscium (RZ Psc) is well-known in the variable star field because of its numerous, irregular optical dips in the past five decades, but the nature of the system is heavily debated in the literature. We present multiyear infrared…
A class of asteroids, called large super-fast rotators (large SFRs), have rotation periods shorter than 2 hours and diameters larger than ~ 0.3 km. They pose challenges to the usual interior rubble-pile structure unless a relatively high…
Main-belt asteroid (6478) Gault was observed to show cometary features in early 2019. To investigate the cause, we conducted {\it BVR} observations at Xingming Observatory, China, from 2019 January to April. The two tails were formed around…
Near-Sun Comet C/2019 Y4 (ATLAS) is the first member of a long-period comet group observed to disintegrate well before perihelion. Here we present our investigation into this disintegration event using images obtained in a 3-day {\it Hubble…
We report a 20-year campaign to track the 1.8 hour photometric wave in the recurrent nova T Pyxidis, using the global telescope network of the Center for Backyard Astrophysics. During 1996-2011, that wave was highly stable in amplitude and…
We report dense lightcurve photometry, $BVR_{c}$ colors and phase - mag curve of (6478) Gault, an active asteroid with sporadic comet-like ejection of dust. We collected optical observations along the 2020 Jul-Nov months during which the…
Comet C/2016 R2 (PanSTARRS) has a peculiar volatile composition, with CO being the dominant volatile as opposed to H$_2$O and one of the largest N$_2$/CO ratios ever observed in a comet. Using observations obtained with the \textit{Spitzer…
We examine the spectral properties of asteroid pairs that were disrupted in the last 2 Myrs to examine whether the site of the fission can be revealed. We studied the possibility that the sub-surface material, perhaps on one hemisphere, has…
RW Aur A is a classical T Tauri star, believed to have undergone a reconfiguration of its circumstellar environment as a consequence of a recent fly-by of its stellar companion, RW Aur B. This interaction stripped away part of the…
P-stars are compact relativistic stars made of deconfined up and down quarks in a chromomagnetic condensate proposed by us long time ago. P-stars do not admit a critical mass thereby they are able to overcome the gravitational collapse to…
We present spatially and spectrally-resolved observations of CH$_3$OH emission from comet C/2012 K1 (PanSTARRS) using The Atacama Large Millimeter/submillimeter Array (ALMA) on 2014 June 28-29. Two-dimensional maps of the line-of-sight…
The rotational state of asteroids is controlled by various physical mechanisms including collisions, internal damping and the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect. We have analysed the changes in magnitude between consecutive…