Related papers: SU Aur: A Deep Fading Event in Visible and Near-In…

The binary system RW Aur consists of two classical T~Tauri stars (CTTSs). The primary recently underwent its second observed major dimming event ($\Delta V\,\sim2\,$mag). We present new, resolved Chandra X-ray and UKIRT near-IR (NIR) data…

We present the discovery of two extended $\sim$0.12 mag dimming events of the weak-lined T-Tauri star V1334. The start of the first event was missed but came to an end in late 2003, and the second began in February 2009, and continues as of…

We report the discovery of a mid-infrared (MIR) flare using WISE data in the center of the nearby Seyfert 1.9 galaxy MCG-02-04-026. The MIR flare began in the first half of 2014, peaked around the end of 2015, and faded in 2017. During…

The Neutron Star Interior Composition Explorer (NICER) on the International Space Station (ISS) observed strong photospheric expansion of the neutron star in 4U 1820-30 during a Type I X-ray burst. A thermonuclear helium flash in the star's…

We present photometric observations of RW Aurigae, a Classical T Tauri system, that reveal two remarkable dimming events. These events are similar to that which we observed in 2010-2011, which was the first such deep dimming observed in RW…

Deep near-infrared (NIR) surveys are critical to our current, and even more to our future, understanding of galaxy evolution in the early universe. In this review I will be discussing the relevance of deep NIR surveys and looking at the…

We report a new changing-look quasar, WISE~J105203.55+151929.5 at $z=0.303$, found by identifying highly mid-IR variable quasars in the WISE/NEOWISE data stream. Compared to multi-epoch mid-IR photometry of a large sample of SDSS-confirmed…

We present the discovery of a large gradual apparent fading event in optical and near-infrared wavelengths in a quasar at z=1.767 by a factor of 20-30 (in optical) over a period of ~20 years in the observed frame. This pronounced fading…

The optical counterpart of the neutron star X-ray binary and well known X-ray burster, 4U 1636-53 (= 4U 1636-536 = V801 Ara) has been well studied for three decades. However to date, no infrared studies have been reported. Our aims are to…

Among the low-mass pre-main sequence stars, a small group called FU Orionis-type objects (FUors) are notable for undergoing powerful accretion outbursts. V1057 Cyg, a classical example of an FUor, went into outburst around 1969-1970, after…

We report the discovery of an exceptional MIR flare in a Type 2 AGN, SDSS J165726.81+234528.1, at $z=0.059$. This object brightened by 3 mag in the Wide-field Infrared Survey Explorer (WISE) $W1$ and $W2$ bands between 2015 and 2017 (and is…

Mapping of near-infrared (NIR) scattered light is a recent method for the study of interstellar clouds, complementing other, more commonly used methods, like dust emission and extinction. Our goal is to study the usability of this method on…

We present results from photometric monitoring of V900 Mon, one of the newly discovered and still under-studied object from FU Orionis type. FUor phenomenon is very rarely observed, but it is essential for stellar evolution. Since we only…

Results of $UBVRIJHKLM$ photometry and $VRI$ polarimetry of a young star RW Aur A observed during unprecedented long and deep (up to $\Delta V \approx 5$ mag) dimming events in 2010-11 and 2014-18 are presented. The polarization degree $p$…

T Tauri has long been the prototypical young pre-main-sequence star. However, it has now been decomposed into a triple system with a complex disk and outflow geometry. We aim to measure the brightness of all three components of the T Tauri…

We obtained late-time optical and near-IR imaging of SN 2008S with the Large Binocular Telescope (LBT). We find that (1) it is again invisible at optical (UBVR) wavelengths to magnitude limits of approximately 25 mag, and (2) while detected…

The lure of a 50 percent reduction in light has brought a multitude of observers and researchers to epsilon Aur every twenty-seven years, but few have paid attention to the system outside of eclipse. As early as the late 1800s, it was clear…

We present monitoring observations of the active T Tauri star RW Aur, from 2010 October to 2015 January, using optical high-resolution (R>10000) spectroscopy with CFHT-ESPaDOnS. Optical photometry in the literature shows bright, stable…

We present observations from the short-term intensive optical campaign (from Sep2019 to Jan2020) of the changing-look Seyfert NGC 3516. This active galactic nucleus is known to have strong optical variability and has changed its type in the…

We carried out BVRI CCD photometric observations in the field of V582 Aur from 2009 August to 2013 February. We acquired high-, medium-, and low-resolution spectroscopy of V582 Aur during this period. To study the pre-outburst variability…