New Constraint on the Atmosphere of (50000) Quaoar from a Stellar Occultation

  title={New Constraint on the Atmosphere of (50000) Quaoar from a Stellar Occultation},
  author={Ko Arimatsu and Ryou Ohsawa and George L. Hashimoto and Seitaro Urakawa and Jun Takahashi and Miyako Tozuka and Yoichi Itoh and Misato Yamashita and Fumihiko Usui and Tsutomu Aoki and Noriaki Arima and Mamoru Doi and Makoto Ichiki and Shiro Ikeda and Yoshifusa Ita and Toshihiro Kasuga and Naoto Kobayashi and Mitsuru Kokubo and Masahiro Konishi and Hiroyuki Maehara and Noriyuki Matsunaga and Takashi Miyata and Mikio Morii and Tomoki Morokuma and Kentaro Motohara and Yoshikazu Nakada and Shin-ichiro Okumura and Shigeyuki Sako and Yuki Sarugaku and Mikiya Sato and Toshikazu Shigeyama and Takao Soyano and Hidenori Takahashi and Ken’ichi Tarusawa and Nozomu Tominaga and Jun-ichi Watanabe and Takuya Yamashita and Makoto Yoshikawa},
  journal={The Astronomical Journal},
We report observations of a stellar occultation by the classical Kuiper Belt object (50000) Quaoar that occurred on 2019 June 28. A single-chord high-cadence (2 Hz) photometry data set was obtained with the Tomo-e Gozen CMOS camera mounted on the 1.05 m Schmidt telescope at Kiso Observatory. The obtained ingress and egress data do not show any indication of atmospheric refraction and allow new 1σ and 3σ upper limits of 6 and 16 nbar, respectively, to be set for the surface pressure of a pure… 

Evidence for a rapid decrease of Pluto’s atmospheric pressure revealed by a stellar occultation in 2019

We report observations of a stellar occultation by Pluto on 2019 July 17. A single-chord high-speed (time resolution = 2 s) photometry dataset was obtained with a CMOS camera mounted on the Tohoku

Detectability of Optical Transients with Timescales of Subseconds

We search for optical transient sources with durations of ∼0.1 to ∼1.3 s using a data set obtained in the Organized Autotelescopes for Serendipitous Event Survey (OASES) observation campaign. Since

The TAOS II Survey: Real-time Detection and Characterization of Occultation Events

The Transneptunian Automated Occultation Survey (TAOS II) is a blind occultation survey with the aim of measuring the size distribution of Trans-Neptunian Objects with diameters in the range of 0.3 ≲

Discovery of the Fastest Early Optical Emission from Overluminous SN Ia 2020hvf: A Thermonuclear Explosion within a Dense Circumstellar Environment

In this Letter we report a discovery of a prominent flash of a peculiar overluminous Type Ia supernova, SN 2020hvf, in about 5 hr of the supernova explosion by the first wide-field mosaic CMOS sensor

Transneptunian Space and the Post-Pluto Paradigm

  • A. Parker
  • Geology, Physics
    The Pluto System After New Horizons
  • 2020
The Pluto system is an archetype for the multitude of icy dwarf planets and accompanying satellite systems that populate the vast volume of the solar system beyond Neptune. New Horizons’ exploration




Here we present high cadence photometry taken by the Acquisition Camera on Gemini South, of a close passage by the ∼540 km radius Kuiper belt object, (50000) Quaoar, of a r′ = 20.2 background star.

The Structure of Titan's Stratosphere from the 28 Sgr Occultation

Abstract A dozen lightcurves obtrained during the ground-based observations of the occulation of 28 Sgr by Titan (3 July 1989) are reanalyzed. Profiles of density and temperature between altitude

Candidate stellar occultations by Centaurs and trans-Neptunian objects up to 2014

Context. We study trans-Neptunian objects (TNOs) from stellar occultations. Aims. We predict stellar occultations from 2012.5 to the end of 2014 by 5 Centaurs and 34 TNOs. Methods. These predictions

Albedo and atmospheric constraints of dwarf planet Makemake from a stellar occultation

The disappearances and reappearances of the star were abrupt, showing that Makemake has no global Pluto-like atmosphere at an upper limit of 4–12 nanobar (1σ) for the surface pressure, although a localized atmosphere is possible.

Direct Measurement of the Size of the Large Kuiper Belt Object (50000) Quaoar

We imaged the recently discovered bright Kuiper belt object (50000) Quaoar with the Hubble Space Telescope High Resolution Camera to directly determine its size. The point-spread function (PSF) of

TNOs are Cool: A Survey of the Transneptunian Region

Over one thousand objects have so far been discovered orbiting beyond Neptune. These trans-Neptunian objects (TNOs) represent the primitive remnants of the planetesimal disk from which the planets

(50000) Quaoar: Surface composition variability

Aims. The goal of this work is to investigate the composition of the surface of (50000) Quaoar and its spatial variability. Methods. We present new continuous spectra from the visible to near-IR

Amateur telescopes discover a kilometre-sized Kuiper belt object from stellar occultation

Kuiper belt objects (KBOs) are thought to be the remnant of the early solar system, and their size distribution provides an opportunity to explore the formation and evolution of the outer solar


We present results derived from the first multi-chord stellar occultations by the transneptunian object (50000) Quaoar, observed on 2011 May 4 and 2012 February 17, and from a single-chord

Detection of Methane on Kuiper Belt Object (50000) Quaoar

The near-infrared spectrum of (50000) Quaoar obtained at the Keck Observatory shows distinct absorption features of crystalline water ice, solid methane, and ethane, and possibly other higher order