Related papers: The BlueWalker 3 Satellite Has Faded
We study the abundance of satellites akin to the brightest, classical dwarf spheroidals around galaxies similar in magnitude and isolation to the Milky Way and M31 in the Sloan Digital Sky Survey. From a combination of photometric and…
[Abridged] We report on a multiwavelength observation of the blazar 3C 454.3 (which we dubbed "crazy diamond") carried out on November 2007 by means of the astrophysical satellites AGILE, INTEGRAL, Swift, the WEBT Consortium, and the…
The dwarf galaxies orbiting a main galaxy suffer strong tidal forces produced by its dark halo. As a consequence, substructures and tidal tails could appear in the satellites. These structures could give us information about the dark matter…
Active galactic nuclei come in many varieties. A minority of them are radio-loud, and exhibit two opposite prominent plasma jets extending from the proximity of the supermassive black hole up to megaparsec distances. When one of the…
We present a coordinated campaign of observations to monitor the brightness of the James Webb Space Telescope (JWST) as it travels toward the second Earth-Sun Lagrange point and unfolds using the network ofUnistellar digital telescopes.…
The U.S. Naval Observatory Robotic Astrometric Telescope (URAT) is observing the northern sky since April 2012 for an astrometric survey. Multiple overlaps per year are performed in a single bandpass (680$-$750 nm) using the "redlens" 20 cm…
We have searched the four brightest objects in the Kuiper belt for the presence of satellites using the newly commissioned Keck Observatory Laser Guide Star Adaptive Optics system. Satellites are seen around three of the four objects: Pluto…
Starlink is a low-Earth orbit (LEO) satellite constellation operated by Space Exploration Technologies Corp. (SpaceX) which aims to provide global satellite internet access. Thus far, most photometric observations of Starlink satellites…
Preliminary results of a systematic study on the simultaneous optical-to-X-rays variability in blazars are presented. Data from Swift observations of four bright gamma-ray blazars (3C 279, ON+231, S5 0716+71, PKS 2155-304) have been…
After extensively explored, broad agreement between observations and theories has been reached that satellites are preferentially aligned with major axes of their host centrals. There are still some issues unsolved on this topic. In this…
The motion of the solar system barycenter with respect to the cosmic microwave background (CMB) induces a very large apparent dipole component into the CMB brightness map at the 3 mK level. In this Letter we discuss another kinematic effect…
3I/ATLAS was discovered on UT 2025 July 1 and joins a limited but growing population of detected $\sim10^2-10^3$ m scale interstellar objects. In this paper we report photometric observations of 3I/ATLAS from the nights of UT 2025 July 3,…
Blazars are a subclass of radio-loud active galactic nuclei (AGNs), where the jet is aligned close to the line of sight. Blazars emission is dominated by non-thermal processes, where Doppler boosted radiation originates from a relativistic…
In December 2009, the bright blazar, 3C 454.3 exhibited a strong outburst in the optical, X-ray and gamma-ray regions. We performed photometric and polarimetric monitoring of this outburst in the optical and near-infrared bands with TRISPEC…
The mean apparent magnitude and the mean of magnitudes adjusted to a standard distance are reported. The illumination phase function for OneWeb satellites is determined and it differs strongly from that of VisorSat spacecraft. Brightness…
The modulation of high-energy transients' (or steadily emitting sources') light curves due to the imperfect alignment of the detector's view axis with the spin axis in a spin-stabilized satellite is derived. It is shown how the orientation…
We use a state-of-the-art physics-based model of electromagnetic scattering to analyze average circular polarization ratios measured for the A and B rings of Saturn at a wavelength of 12.6 cm. This model is directly based on the Maxwell…
The galaxy cluster Abell 781 West has been viewed as a challenge to weak gravitational lensing mass calibration, as Cook and dell'Antonio (2012) found that the weak lensing signal-to-noise in three independent sets of observations was…
We use the fourth data release of the Sloan Digital Sky Survey to investigate the orientations of 4289 satellite galaxies with respect to their hosts. The orientation of the satellites is inconsistent with a random distribution at the…
We carry out deep imaging of the Milky Way satellite galaxies, Bootes III and Draco, with WFST as one pilot observing program to demonstrate the capability of WFST. Combining catalogs with PS1 DR2 and Gaia DR3, we derive proper motions for…