MAGIQ at the W. M. Keck Observatory: initial deployment of a new acquisition, guiding, and image quality monitoring system

The W. M. Keck Observatory has completed the development and initial deployment of MAGIQ, the Multi-function Acquisition, Guiding and Image Quality monitoring system. MAGIQ is an integrated system for acquisition, guiding and image quality measurement for the Keck telescopes. This system replaces the acquisition and guiding hardware and software for existing instruments at the Observatory and is now the standard for visible wavelength band acquisition cameras for future instrumentation. In this paper we report on the final design and implementation of this new system, which includes three major components: a visible wavelength band acquisition camera, image quality measurement capability, and software for acquisition, guiding and image quality monitoring. The overall performance is described, as well as the details of our approach to integrating low order wavefront sensing capability in order to provide closed loop control of telescope focus

Drift Rates of Major Neptunian Features between 2018 and 2021

Using near-infrared observations of Neptune from the Keck and Lick Observatories, and the Hubble Space Telescope in combination with amateur datasets, we calculated the drift rates of prominent infrared-bright cloud features on Neptune between 2018 and 2021. These features had lifespans of $\sim 1$ day to $\geq$1 month and were located at mid-latitudes and near the south pole. Our observations permitted determination of drift rates via feature tracking. These drift rates were compared to three zonal wind profiles describing Neptune's atmosphere determined from features tracked in H band (1.6 $\mu m$), K' band (2.1 $\mu m$), and Voyager 2 data at visible wavelengths. Features near $-70 \deg$ measured in the F845M filter (845nm) were particularly consistent with the K' wind profile. The southern mid-latitudes hosted multiple features whose lifespans were $\geq$1 month, providing evidence that these latitudes are a region of high stability in Neptune's atmosphere. We also used HST F467M (467nm) data to analyze a dark, circumpolar wave at $- 60 \deg$ latitude observed on Neptune since the Voyager 2 era. Its drift rate in recent years (2019-2021) is $4.866 \pm 0.009 \deg$/day. This is consistent with previous measurements by Karkoschka (2011), which predict a $4.858 \pm 0.022 \deg$/day drift rate during these years. It also gained a complementary bright band just to the north.Comment: 29 pages, 13 figures, accepted to Icaru

Io’s Volcanic Activity from Time Domain Adaptive Optics Observations: 2013–2018

We present measurements of the near-infrared brightness of Io's hot spots derived from 2 to 5 μm imaging with adaptive optics on the Keck and Gemini N telescopes. The data were obtained on 271 nights between 2013 August and the end of 2018, and include nearly 1000 detections of over 75 unique hot spots. The 100 observations obtained between 2013 and 2015 have been previously published in de Kleer & de Pater the observations since the start of 2016 are presented here for the first time, and the analysis is updated to include the full five-year data set. These data provide insight into the global properties of Io's volcanism. Several new hot spots and bright eruptions have been detected, and the preference for bright eruptions to occur on Io's trailing hemisphere noted in the 2013–2015 data is strengthened by the larger data set and remains unexplained. The program overlapped in time with Sprint-A/EXCEED and Juno observations of the Jovian system, and correlations with transient phenomena seen in other components of the system have the potential to inform our understanding of the impact of Io's volcanism on Jupiter and its neutral/plasma environment

Io’s Volcanic Activity from Time Domain Adaptive Optics Observations: 2013–2018

We present measurements of the near-infrared brightness of Io's hot spots derived from 2 to 5 μm imaging with adaptive optics on the Keck and Gemini N telescopes. The data were obtained on 271 nights between 2013 August and the end of 2018, and include nearly 1000 detections of over 75 unique hot spots. The 100 observations obtained between 2013 and 2015 have been previously published in de Kleer & de Pater the observations since the start of 2016 are presented here for the first time, and the analysis is updated to include the full five-year data set. These data provide insight into the global properties of Io's volcanism. Several new hot spots and bright eruptions have been detected, and the preference for bright eruptions to occur on Io's trailing hemisphere noted in the 2013–2015 data is strengthened by the larger data set and remains unexplained. The program overlapped in time with Sprint-A/EXCEED and Juno observations of the Jovian system, and correlations with transient phenomena seen in other components of the system have the potential to inform our understanding of the impact of Io's volcanism on Jupiter and its neutral/plasma environment

MAGIQ at the W. M. Keck Observatory: initial deployment of a new acquisition, guiding, and image quality monitoring system

The W. M. Keck Observatory has completed the development and initial deployment of MAGIQ, the Multi-function Acquisition, Guiding and Image Quality monitoring system. MAGIQ is an integrated system for acquisition, guiding and image quality measurement for the Keck telescopes. This system replaces the acquisition and guiding hardware and software for existing instruments at the Observatory and is now the standard for visible wavelength band acquisition cameras for future instrumentation. In this paper we report on the final design and implementation of this new system, which includes three major components: a visible wavelength band acquisition camera, image quality measurement capability, and software for acquisition, guiding and image quality monitoring. The overall performance is described, as well as the details of our approach to integrating low order wavefront sensing capability in order to provide closed loop control of telescope focus

Parent Volatiles in Comet 9P/Tempel 1: Before and After Impact

We quantified eight parent volatiles (H_2O, C_2H_6, HCN, CO, CH_3OH, H_2CO, C_2H_2, and CH_4) in the Jupiter-family comet Tempel 1 using high-dispersion infrared spectroscopy in the wavelength range 2.8 to 5.0 micrometers. The abundance ratio for ethane was significantly higher after impact, whereas those for methanol and hydrogen cyanide were unchanged. The abundance ratios in the ejecta are similar to those for most Oort cloud comets, but methanol and acetylene are lower in Tempel 1 by a factor of about 2. These results suggest that the volatile ices in Tempel 1 and in most Oort cloud comets originated in a common region of the protoplanetary disk

Dickens in the New Millennium

This special issue of the Cahiers victoriens et édouardiens initially published in 2012 means to celebrate Charles Dickens’s bicentenary of his birthday and offers a selection of articles derived from the yearly conference of the Dickens Society which took place in Aix-en-Provence. The aim of this volume is to consider how Dickens’s fiction is understood, interpreted and taught nowadays, and whether it answers twenty-first-century concerns. The essays collected here also examine how today’s public views the mid-Victorian period through Dickens’s writing. The editors would like to thank all the authors for their contributions to the present volume as well as the research centres which made this publication possible : the LERMA (Laboratoire d’Études et de Recherche sur le Monde Anglophone – Université d’Aix-Marseille 1), EMMA (Études Montpelliéraines du Monde Anglophone – Université de Montpellier 3), CECILLE (Centre d’Études en Civilisations, Langues et Littératures Étrangères – Université Charles de Gaulle Lille 3), the PULM (Presses Universitaires de la Méditerranée), the Dickens Society and the Dickens Museum for their kind permission to use Robert William Buss’s ‘Dickens’s Dream’. The volume consists of six sections. ‘Making a Start on Dickens’ contains three essays focusing on teaching Dickens or stressing the relevance of Dickens’s work in the information age. ‘Iconic and Cinematic Dickens’ is about the visual potentialities of Dickens’s work in book illustrations or cinematic adaptations. ‘Reading Dickens’ reviews the value of reading itself in the Victorian author’s fiction as well as his recourse to sentimentality or to a double narrating stance. The articles in ‘Scientific Dickens’ show the contribution that science and the history of science still bring to the interpretation of his work today. ‘Hypo/Hyper Dickens’ explores another contribution to his legacy in the form of Dickensian doubles, either in his own fiction or as post-Dickens neo-Victorian rewritings. Finally ‘Metafictional, Prototypical and Archetypal Dickens’ studies a selection of metanarratives (mythological, apocalyptic, geological), which Dickens used to decipher the signs of his times. Ce numéro hors série des Cahiers victoriens et édouardiens entend célébrer le bicentenaire de la naissance de Charles Dickens (1812-1870). Il réunit une sélection d’articles dérivés du Congrès de la Dickens Society qui s’est tenu à Aix-en-Provence en 2012. Le but de cette publication est d’évaluer la façon dont la fiction de Dickens est comprise, interprétée et enseignée aujourd’hui, et de voir si cette fiction répond aux préoccupations du XXIe siècle. Les articles regroupés ici examinent également la manière dont le public d’aujourd’hui considère la période victorienne à travers les écrits de Charles Dickens. Les rédacteurs en chef remercient les auteurs des contributions de ce volume ainsi que les centres de recherche qui en ont permis la publication : le LERMA (Laboratoire d’Études et de Recherche sur le Monde Anglophone – Université d’Aix-Marseille 1), EMMA (Études Montpelliéraines du Monde Anglophone – Université de Montpellier 3), CECILLE (Centre d’Études en Civilisations, Langues et Littératures Étrangères – Université Charles de Gaulle Lille 3), les PULM (Presses Universitaires de la Méditerranée), la Dickens Society et le Dickens Museum pour leur autorisation de faire usage du tableau de Robert William Buss, ‘Dickens’s Dream’, comme couverture. Le volume se compose de six sections. ‘Making a Start on Dickens’ regroupe trois articles qui se concentrent sur l’enseignement des oeuvres de Dickens dans un contexte secondaire ou universitaire ou sur leur pertinence dans le monde numérique et connecté d’aujourd’hui. ‘Iconic and Cinematic Dickens’ se concentre sur les potentialités visuelles de ses œuvres par le biais des illustrations publiées dans des éditions posthumes ou des adaptations cinématographiques. ‘Reading Dickens’ considère la valeur qu’attribuait l’auteur victorien à la lecture au travers de ses fictions, son recours au sentimentalisme ou à une double instance narrative. Les articles de la section intitulée ‘Scientific Dickens’ montre la contribution que la science et l’histoire de la science continuent d’apporter à l’interprétation de ses oeuvres aujourdhui. ‘Hypo/Hyper Dickens’ explore une autre contribution à son patrimoine sous la forme des doubles dickensiens, soit au sein de ses œuvres, soit dans le domaine des réécritures néo-victoriennes. Enfin, ‘Metafictional, Prototypical and Archetypal Dickens’ aborde un ensemble de méta-récits (mythologique, apocalyptique, géologique), auxquels Dickens a eu recours pour déchiffrer les signes de son temps