Related papers: Limits on Quaoar's Atmosphere
We report observations of a stellar occultation by the classical Kuiper belt object (50000) Quaoar occurred on 28 June 2019. A single-chord high-cadence (2 Hz) photometry dataset was obtained with the Tomo-e Gozen CMOS camera mounted on the…
Recent stellar occultations have allowed accurate instantaneous size and apparent shape determinations of the large Kuiper belt object (50000)~Quaoar and the detection of two rings with spatially variable optical depths. In this paper we…
Observations of stellar occultations have revealed that small bodies are capable of hosting ring systems. The trans-Neptunian object (TNO) Quaoar, is the host of an enigmatic ring system, with two rings located well-outside the Roche limit.…
A modified Baker-Nunn camera was used to conduct a wide-field survey of 1428 square degrees of sky near the ecliptic in search of bright Kuiper Belt objects and Centaurs. This area is an order of magnitude larger than any previously…
At 30-50 K, the temperatures typical for surfaces in the Kuiper Belt (e.g. Stern & Trafton 2008), only seven species have sublimation pressures higher than 1 nbar (Fray & Schmitt 2009): Ne, N$_2$, CO, Ar, O$_2$, CH$_4$, and Kr. Of these,…
The population of the Kuiper Belt within 50 AU of the Sun has likely been severely depleted by gravitational perturbations from the giant planets, particularly Neptune. The density of Kuiper Belt objects is expected to be two orders of…
Quaoar is a classical Trans-Neptunian Object (TNO) with an area equivalent diameter of 1,100 km and an orbital semi-major axis of 43.3 astronomical units. Based on stellar occultations observed between 2018 and 2021, an inhomogeneous ring…
We present a high-resolution (R=140,000) spectrum of the bright quasar HE0001-2340 (z=2.26), obtained with ESPRESSO at the Very Large Telescope. We analyse three systems at z=0.45, z=1.65, and z=2.19 using multiple-component Voigt-profile…
Stellar occultation is a powerful technique that allows the determination of some physical parameters of the occulting object. The result depends on the photometric accuracy, the temporal resolution, and the number of chords obtained. Space…
We compute the temperature and IR signal of particles of radius $a$ and albedo $\alpha$ at heliocentric distance $R$, taking into account the emissivity effect, and give an interpolating formula for the result. We compare with analyses of…
The Kuiper belt is a remnant of the primordial Solar System. Measurements of its size distribution constrain its accretion and collisional history, and the importance of material strength of Kuiper belt objects (KBOs). Small, sub-km sized,…
The strong, nearly wavelength-independent absorption cross section of aerosols produces featureless exoplanet transmission spectra, limiting our ability to characterize their atmospheres. Here we show that even in the presence of…
Almost all of the $>600$ known Kuiper belt objects (KBOs) have been discovered within 50 AU of the Sun. One possible explanation for the observed lack of KBOs beyond 50 AU is that the distant Kuiper belt is dynamically very cold, and thus…
We use photometric data, from the optical to the mm for a large sample of optically selected radio-quiet quasars, at low and high redshifts, to test emission models from circum-nuclear dusty torii around them. Model parameters, such as dust…
From the analysis of the CII fine-structure population ratio in the damped Ly_alpha system at z = 3.025 toward the quasar Q0347--3819 we derive an upper bound of 14.6 (+/- 0.2) K on the cosmic microwave background temperature regardless the…
Here we report WFPC2 observations of the Quaoar-Weywot Kuiper belt binary. From these observations we find that Weywot is on an elliptical orbit with eccentricity of 0.14 {\pm} 0.04, period of 12.438 {\pm} 0.005 days, and a semi-major axis…
The results of a search for sub-km Kuiper Belt Objects (KBOs) with the method of serendipitous stellar occultations are reported. Photometric time series were obtained on the 1.8m telescope at the Dominion Astrophysical Observatory (DAO) in…
We present a detailed dynamical analysis of the Quaoar-Weywot system based on nearly 20 years of high-precision astrometric data, including new HST observations and stellar occultations. Our study reveals that Weywot's orbit deviates…
Recent observations show activity in long-period comet C/2017 K2 at heliocentric distances beyond the orbit of Uranus. With this as motivation, we constructed a simple model that takes a detailed account of gas transport modes and simulates…
When a main sequence star evolves into a red giant and its Kuiper Belt Object's (KBO's) reach a temperature of about 170 K, the dust released during the rapid ice-sublimation of these cometary bodies may lead to a detectable infrared excess…