相关论文: Carbon monoxide in the distantly active Centaur (6…

The Centaurs are the small solar system bodies intermediate between the active inner solar system Jupiter Family Comets and their inactive progenitors in the trans-Neptunian region. Among the fraction of Centaurs which show comet-like…

Context. More than ten Centaurs are now known to have cometary activity at large heliocentric distance (i.e. $\simeq$ 5-13 AU). Among these objects, 174P/Echeclus which showed cometary activity at 13 AU from the Sun, is a unique case,…

The Centaur (60558) Echeclus was discovered on March 03, 2000, orbiting between the orbits of Jupiter and Uranus. After exhibiting frequent outbursts, it also received a comet designation, 174P. If the ejected material can be a source of…

29P/Schwassmann Wachmann is an unusual solar system object. Originally classified as a short-period comet, it is now known as a Centaur that recently transferred to its current orbit, and may become a Jupiter Family comet. It has exhibited…

It has been suggested that centaurs may lose their red surfaces and become bluer due to the onset of cometary activity, but the way in which cometary outbursts affect the surface composition and albedo of active centaurs is poorly…

Centaurs are minor solar system bodies with orbits transitioning between those of Trans-Neptunian Scattered Disk objects and Jupiter Family comets. 39P/Oterma is a frequently active Centaur that has recently held both Centaur and JFC…

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.…

29P/Schwassmann-Wachmann 1 is a distant Centaur/comet, showing persistent CO-driven activity and frequent outbursts. We used the Herschel space observatory in 2010, 2011, and 2013 to observe H$_2$O and NH$_3$ and to image the dust coma.…

We report the detection of several emission bands in the CO Fourth Positive Group from comet 103P/Hartley during ultraviolet spectroscopic observations from the Hubble Space Telescope (HST) on 2010 November 4 near the time of closest…

We present observations showing in-bound long-period comet C/2017 K2 (PANSTARRS) to be active at record heliocentric distance. Nucleus temperatures are too low (60 K to 70 K) either for water ice to sublimate or for amorphous ice to…

Jupiter-family comet (JFC) P/2021 HS (PANSTARRS) only exhibits a coma within a few weeks of its perihelion passage at 0.8~au, which is atypical for a comet. Here we present an investigation into the underlying cause using serendipitous…

Centaurs are minor planets thought to have originated in the outer Solar System region known as the Kuiper Belt. Active Centaurs enigmatically display comet-like features (e.g., tails, comae) even though they orbit in the gas giant region…

The Outer Scutum-Centaurus arm (OSC) is the most distant molecular spiral arm known in the Milky Way. The OSC may be the very distant end of the well-known Scutum-Centaurus arm, which stretches from the end of the Galactic bar to the outer…

Centaurs are inward-scattered Kuiper belt objects, with some exhibiting comet-like activity. The physical mechanisms powering this activity remain poorly understood, with carbon monoxide (CO) sublimation or the crystallization of amorphous…

Activity of most comets near the Sun is dominated by sublimation of frozen water, the most abundant ice in comets. Some comets, however, are active well beyond the water-ice sublimation limit of ~3 AU. Three bodies dominate the…

The extraordinary 2021 September-October outburst of Centaur 29P/Schwassmann-Wachmann 1 afforded an opportunity to test the composition of primitive Kuiper disk material at high sensitivity. We conducted nearly simultaneous multi-wavelength…

We aim to determine the production rates of several parent and product volatiles and the 12C/13C isotopic carbon ratio in the long-period comet C/2004 Q2 (Machholz), which is likely to originate from the Oort Cloud. The line emission from…

We present high angular resolution Submillimeter Array observations ofthe outbursting Jupiter family comet 17P/Holmes on 2007 October 26-29, achieving a spatial resolution of 2.5", or ~3000 km at the comet distance. The observations…

We present near-infrared spectroscopy of the NGC 5128 supernova SN 2016adj in the first 2 months following discovery. We report the detection of first overtone carbon monoxide emission at $\sim58.2$ d after discovery, one of the earliest…

We observed comet C/2016 R2 (PANSTARRS) with the ARO 10-m SMT, and report the first detection of CO emission from this comet with amounts high enough to be the primary driver of activity. We obtained spectra and maps of the CO J=2-1…