Search Publications
Chemistry of Complex Organic Molecules in the V883 Ori Disk Revealed by ALMA Band 3 Observations
Aikawa, Yuri; Nomura, Hideko; Yamato, Yoshihide +3 more
Complex organic molecules (COMs) in protoplanetary disks are key to understanding the origin of volatiles in comets in our solar system, yet the chemistry of COMs in protoplanetary disks remains poorly understood. Here, we present Atacama Large Millimeter/submillimeter Array Band 3 observations of the disk around the young outbursting star V883 Or…
The Return of the Rosetta Target: Keck Near-infrared Observations of Comet 67P/Churyumov-Gerasimenko in 2021
Ootsubo, Takafumi; Villanueva, Geronimo L.; Cochran, Anita L. +20 more
High-resolution near-infrared ground-based spectroscopic observations of comet 67P/Churyumov-Gerasimenko near its maximum activity in 2021 were conducted from the W. M. Keck Observatory, using the facility spectrograph NIRSPEC. 67P is the best-studied comet to date because of the unprecedented detail and insights provided by the Rosetta mission du…
Analysis of Hybrid Gas-Dust Outbursts Observed at 67P/Churyumov-Gerasimenko
Parker, Joel Wm.; Bertaux, Jean-Loup; Stern, S. Alan +14 more
Cometary outbursts offer a valuable window into the composition of comet nuclei with their forceful ejection of dust and volatiles in explosive events, revealing the interior components of the comet. Understanding how different types of outbursts influence the dust properties and volatile abundances, to better interpret what signatures can be attr…
Spatial Distribution of Ultraviolet Emission from Cometary Activity at 67P/Churyumov-Gerasimenko
Parker, Joel Wm.; Bertaux, Jean-Loup; Weaver, Harold A. +16 more
The Alice ultraviolet spectrograph on board the Rosetta orbiter provided the first near-nucleus ultraviolet observations of a cometary coma from arrival at comet 67P/Churyumov-Gerasimenko in 2014 August through 2016 September. The characterization of atomic and molecular emissions in the coma revealed the unexpected contribution of dissociative el…
Probing the Evolutionary History of Comets: An Investigation of the Hypervolatiles CO, CH4, and C2H6 in the Jupiter-family Comet 21P/Giacobini-Zinner
Feaga, Lori M.; Cochran, Anita L.; Vervack, Ronald J., Jr. +13 more
Understanding the cosmogonic record encoded in the parent volatiles stored in cometary nuclei requires investigating whether evolution (thermal or otherwise) has modified the composition of short-period comets during successive perihelion passages. As the most volatile molecules systematically observed in comets, the abundances of CO, CH4
Carbonyl Sulfide (OCS): Detections in Comets C/2002 T7 (LINEAR), C/2015 ER61 (PanSTARRS), and 21P/Giacobini-Zinner and Stringent Upper Limits in 46P/Wirtanen
Vervack, Ronald J., Jr.; Kawakita, Hideyo; DiSanti, Michael A. +6 more
Carbonyl sulfide (OCS) is one of the sulfur-bearing molecules detected in different astronomical environments, including comets. The present-day sulfur chemistry in comets may reveal much about the origin of these ices and their subsequent processing history. Cometary sulfur molecules such as H2S, H2CS, SO2, SO, CS…
Low-activity Main-belt Comet 133P/Elst-Pizarro: New Constraints on Its Albedo, Temperature, and Active Mechanism from a Thermophysical Perspective
Ip, Wing-Huen; Hsia, Chih Hao; Yu, Liang Liang
133P/Elst-Pizarro is the first recognized main-belt comet, but we still know little about its nucleus. First we use mid-infrared data of Spitzer MIPS, Spitzer IRS, and the Wide-field Infrared Survey Explorer to estimate its effective diameter, ${D}_{\mathrm{eff}}={3.9}_{-0.3}^{+0.4}$ km, geometric albedo, ${p}_{{\rm{v}}}=0.074\pm 0.013$ , and mean…
In-flight Characterization and Calibration of the Juno-ultraviolet Spectrograph (Juno-UVS)
Gérard, Jean-Claude; Kammer, Joshua A.; Gladstone, G. Randall +9 more
Juno is the first polar orbiter around Jupiter. Juno possesses a suite of instruments designed to measure the electron and ion populations in the Jupiter magnetosphere, leading to the powerful Jovian aurorae. The Ultraviolet Spectrograph onboard Juno (Juno-UVS) is a photon-counting imaging spectrograph (68-210 nm), designed to observe and characte…
The Convective Electric Field Influence on the Cold Plasma and Diamagnetic Cavity of Comet 67P
Henri, Pierre; Nilsson, Hans; Edberg, Niklas J. T. +5 more
We studied the distribution of cold electrons (<1 eV) around comet 67P/Churyumov-Gerasimenko with respect to the solar wind convective electric field direction. The cold plasma was measured by the Langmuir Probe instrument and the direction of the convective electric field {\boldsymbol{E}} conv = -{\boldsymbol{v}} × {\boldsymbol{B}} …
Stellar Occultation by Comet 67P/Churyumov-Gerasimenko Observed with Rosetta's Alice Far-ultraviolet Spectrograph
Parker, Joel Wm.; Bertaux, Jean-Loup; Stern, S. Alan +13 more
Following our previous detection of ubiquitous {{{H}}}2{{O}} and {{{O}}}2 absorption against the far-ultraviolet continuum of stars located near the nucleus of Comet 67P/Churyumov-Gerasimenko, we present a serendipitously observed stellar occultation that occurred on 2015 September 13, approximately one month after the comet’…