Matthew M. Knight
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MS V6 with Figures
Grism Spectroscopy of Comet Lulin Swift UVOT Grism Spectroscopy of Comets: A First Application to C/2007 N3 (Lulin) D. Bodewits1,2, G. L. Villanueva2,3, M. J. Mumma2, W. B. Landsman4, J. A. Carter5, and A. M. Read5 Submitted to the Astronomical Journal on 16th February, 2010 Revised version October 21st, 2010 1 NASA Postdoctoral Fellow, [email protected] 2 NASA Goddard Space Flight Center, Solar System Exploration Division, Mailstop 690.3, Greenbelt, MD 20771, USA 3 Dept. of Physics, Catholic University of America, Washington DC 20064, USA 4 NASA Goddard Space Flight Center, Astrophysics Science Division, Mailstop 667, Greenbelt, MD 20771, USA 5 Dept. of Physics and Astronomy, Leicester University, Leicester LE1 7RH, UK 8 figures, 4 tables Key words: Comets: Individual (C/2007 N3 (Lulin)) – Methods: Data Analysis – Techniques: Image Spectroscopy – Ultraviolet: planetary systems Abstract We observed comet C/2007 N3 (Lulin) twice on UT 28 January 2009, using the UV grism of the Ultraviolet and Optical Telescope (UVOT) on board the Swift Gamma Ray Burst space observatory. Grism spectroscopy provides spatially resolved spectroscopy over large apertures for faint objects. We developed a novel methodology to analyze grism observations of comets, and applied a Haser comet model to extract production rates of OH, CS, NH, CN, C3, C2, and dust. The water production rates retrieved from two visits on this date were 6.7 ± 0.7 and 7.9 ± 0.7 x 1028 molecules s-1, respectively. Jets were sought (but not found) in the white-light and ‘OH’ images reported here, suggesting that the jets reported by Knight and Schleicher (2009) are unique to CN. -
CYANOGEN JETS and the ROTATION STATE of COMET MACHHOLZ (C/2004 Q2) Tony L
The Astronomical Journal, 133:2001Y2007, 2007 May # 2007. The American Astronomical Society. All rights reserved. Printed in U.S.A. CYANOGEN JETS AND THE ROTATION STATE OF COMET MACHHOLZ (C/2004 Q2) Tony L. Farnham1 Department of Astronomy, University of Maryland, College Park, MD 20742, USA; [email protected] Nalin H. Samarasinha2 National Optical Astronomy Observatory, Tucson, AZ 85719, USA; and Planetary Science Institute, Tucson, AZ 85719, USA Be´atrice E. A. Mueller1 Planetary Science Institute, Tucson, AZ 85719, USA and Matthew M. Knight1 Department of Astronomy, University of Maryland, College Park, MD 20742, USA Received 2006 June 16; accepted 2007 January 25 ABSTRACT Extensive observations of Comet Machholz (C/2004 Q2) from 2005 February, March, and April were used to derive a number of the properties of the comet’s nucleus. Images were obtained using narrowband comet filters to isolate the CN morphology. The images revealed two jets that pointed in roughly opposite directions relative to the nucleus and changed on hourly timescales. The morphology repeated itself in a periodic manner, and this fact was used to determine a rotation period for the nucleus of 17:60 Æ 0:05 hr. The morphology was also used to estimate a pole orientation of R:A: ¼ 50,decl: ¼þ35, and the jet source locations were found to be on opposite hemispheres at mid- latitudes. The longitudes are also about 180 apart, although this is not well constrained. The CN features were mea- sured to be moving at about 0.8 km sÀ1, which is close to the canonical value typically quoted for gas outflow. -
My Views on the Bible***
ABOUT THIS CURRENT VERSION I have made a few minor corrections in spelling and a handful of remarks for clarity's sake in the past few days. All the facts from the 3rd modification in 2012, however, remain unchanged despite the several great changes around the world. Thang Za Dal Hamburg August 19, 2020. MY VIEWS ON THE BIBLE AND CURRENT WORLD AFFAIRS (3rd Modification) It is the 3rd modification of my “Interview” which was first publicized back on March 23, 1987. The original version was put on this website between March 2007 and May 2009. Then it was replaced in June 2009 with the 1st modification until March 23, 2012. Then once again it was replaced with the 2nd Modification on March 24, 2012, which remained on the website until September 6, 2012. Although I could have had expanded or changed radically many parts of the original version in light of the major changes in world affairs that have been taking place since 1987 I haven‘t done that. Only the styles of expression - and not the basic essences - of theological issues have been changed for the sake of clearity. Nearly all non-theological issues remain unchanged from the original version. In this present version only a very few changes and additions are made from the previous one. I have just added a new Item called On Western Philosophy (# 100), just because a number of people who have read my paper wanted to know about my opinion on this topic and I suppose there could probably be some more who have the same wish. -
THE GREAT CHRIST COMET CHRIST GREAT the an Absolutely Astonishing Triumph.” COLIN R
“I am simply in awe of this book. THE GREAT CHRIST COMET An absolutely astonishing triumph.” COLIN R. NICHOLL ERIC METAXAS, New York Times best-selling author, Bonhoeffer The Star of Bethlehem is one of the greatest mysteries in astronomy and in the Bible. What was it? How did it prompt the Magi to set out on a long journey to Judea? How did it lead them to Jesus? THE In this groundbreaking book, Colin R. Nicholl makes the compelling case that the Star of Bethlehem could only have been a great comet. Taking a fresh look at the biblical text and drawing on the latest astronomical research, this beautifully illustrated volume will introduce readers to the Bethlehem Star in all of its glory. GREAT “A stunning book. It is now the definitive “In every respect this volume is a remarkable treatment of the subject.” achievement. I regard it as the most important J. P. MORELAND, Distinguished Professor book ever published on the Star of Bethlehem.” of Philosophy, Biola University GARY W. KRONK, author, Cometography; consultant, American Meteor Society “Erudite, engrossing, and compelling.” DUNCAN STEEL, comet expert, Armagh “Nicholl brilliantly tackles a subject that has CHRIST Observatory; author, Marking Time been debated for centuries. You will not be able to put this book down!” “An amazing study. The depth and breadth LOUIE GIGLIO, Pastor, Passion City Church, of learning that Nicholl displays is prodigious Atlanta, Georgia and persuasive.” GORDON WENHAM, Adjunct Professor “The most comprehensive interdisciplinary of Old Testament, Trinity College, Bristol synthesis of biblical and astronomical data COMET yet produced. -
Arxiv:1011.4313V1
Accepted to ApJ: October 23, 2010 GALEX FUV Observations of Comet C/2004 Q2 (Machholz): The Ionization Lifetime of Carbon Jeffrey P. Morgenthaler Planetary Science Institute, 1700 E. Fort Lowell, Ste 106, Tucson, AZ 85719, USA [email protected] Walter M. Harris Department of Applied Sciences, University of California at Davis, One Shields Ave., Davis, CA 95616, USA Michael R. Combi Department of Atmospheric, Oceanic and Space Sciences, The University of Michigan, 2455 Hayward St. Ann Arbor, MI 48109, Ann Arbor, MI, USA Paul D. Feldman Department of Physics and Astronomy, The Johns Hopkins University Charles and 34th Streets, Baltimore, Maryland 21218, USA Harold A. Weaver Space Department, Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723-6099, USA ABSTRACT 3 arXiv:1011.4313v1 [astro-ph.EP] 18 Nov 2010 We present a measurement of the lifetime of ground state atomic carbon, C( P), against ionization processes in interplanetary space and compare it to the lifetime ex- pected from the dominant physical processes likely to occur in this medium. Our mea- surement is based on analysis of a far ultraviolet (FUV) image of comet C/2004 Q2 (Machholz) recorded by the Galaxy Evolution Explorer (GALEX) on 2005 March 1. The bright C I 1561 A˚ and 1657 A˚ multiplets dominate the GALEX FUV band. We used the image to create high signal-to-noise ratio radial profiles that extended beyond 1×106 km from the comet nucleus. Our measurements yielded a total carbon lifetime of 7.1 – 9.6×105 s (ionization rate of 1.0 – 1.4×10−6 s−1) when scaled to 1 AU. -
Comets in UV
Comets in UV B. Shustov1 • M.Sachkov1 • Ana I. G´omez de Castro 2 • Juan C. Vallejo2 • E.Kanev1 • V.Dorofeeva3,1 Abstract Comets are important “eyewitnesses” of So- etary systems too. Comets are very interesting objects lar System formation and evolution. Important tests to in themselves. A wide variety of physical and chemical determine the chemical composition and to study the processes taking place in cometary coma make of them physical processes in cometary nuclei and coma need excellent space laboratories that help us understand- data in the UV range of the electromagnetic spectrum. ing many phenomena not only in space but also on the Comprehensive and complete studies require for ad- Earth. ditional ground-based observations and in-situ exper- We can learn about the origin and early stages of the iments. We briefly review observations of comets in evolution of the Solar System analogues, by watching the ultraviolet (UV) and discuss the prospects of UV circumstellar protoplanetary disks and planets around observations of comets and exocomets with space-born other stars. As to the Solar System itself comets are instruments. A special refer is made to the World Space considered to be the major “witnesses” of its forma- Observatory-Ultraviolet (WSO-UV) project. tion and early evolution. The chemical composition of cometary cores is believed to basically represent the Keywords comets: general, ultraviolet: general, ul- composition of the protoplanetary cloud from which traviolet: planetary systems the Solar System was formed approximately 4.5 billion years ago, i.e. over all this time the chemical composi- 1 Introduction tion of cores of comets (at least of the long period ones) has not undergone any significant changes. -
The Photometric Study of the Comet C/2007 N3 (Lulin)
The Photometric Study of the Comet C/2007 N3 (Lulin) Machchema Jankla, Kamal Baha, Nakared Inthana and Krit Boonsiriseth Mahidol Wittayanusorn School,Nakhonpathom; Chakkham Khanathon School,Lamphun;Azizstan School, Patani; Chulalongkorn University Demonstration Elementary School, Bangkok,Thailand [email protected], [email protected], [email protected] Abstract This work studies the brightness of comet C/2007 N3 (Lulin) when it came closer to the Earth in 2009. We found that the comet’s brightness brightened from 12 mag in January 2009 and increased until the 25th of February when the brightness peaked. The brightness reached the highest magnitude which was 6.44 that day and then it started to decrease. We compare our observations with the theoretical prediction from the JPL Horizons Ephemeris and found that the light curve has similar shape but the normalization differs slightly. Introduction The comet C/2007 N3 (Lulin) comet is a special comet in this decade because it had two tails in a different directions (the “anti-tail”). Lulin’s orbit is nearly parallel with the orbit of the earth so when it got closer to the earth, the dust tail that is left along the comet’s otbit appeared in one direction while the ion tail which is caused by the solar wind and always points directly away from the Sun appears to be in the opposite direction. The relative position between the Earth, the comet and the Sun at the time of Lulin’s closest approach which resulted in Lulin’s tails pointing to different directions is shown in Fig. 1. We studied this unique comet photometrically by observing it with the Robotic Optical Transient Search Experiment (ROTSE)’s 0.45-meter robotic telescope (www.rotse.net) in Texas, USA, remotely from January – February 2009. -
The Comet's Tale and (Spacewatch), 1998 M5 Need of Observation
THE COMET’S TALE Newsletter of the Comet Section of the British Astronomical Association Volume 6, No 2 (Issue 12), 1999 October THE SECOND INTERNATIONAL WORKSHOP ON COMETARY ASTRONOMY New Hall, Cambridge, 1999 August 14 - 16 After months of planning and much hard work the participants for the second International Workshop on Cometary Astronomy began to assemble at New Hall, Cambridge on the afternoon and evening of Friday, August 13th. New Hall is one of the more recent Cambridge colleges and includes a centre built for Japanese students as well as accommodation for the graduate and undergraduate students. It is a women’s college and a few participants were later disturbed by the night porter doing his rounds and making sure that all ground floor windows were closed. A hearty dinner was provided, but afterwards I had to leave to continue last minute preparations for the morning. He had searched 1000 hours since Most discoveries were from On Saturday morning, Dan Green 1994 without a discovery. If the Japan, USA and Australia. and Jon Shanklin made a few Edgar Wilson award had been in Southern Hemisphere observers opening announcements. We had operation he would have netted an only discover southern declination nine comet discoverers present average of $4000 a year, though comets, however northern and five continents were some years would be more hemisphere observers find them in represented. The next meeting rewarding and others less. His both hemispheres. There is no would take place in 4 – 5 years search technique is to scan significant trend in discovery time, possibly in America. -
Comet Kohoutek (NASA 990 Convair )
Madrid, UCM, Oct 27, 2017 Comets in UV Shustov B., Sachkov M., Savanov I. Comets – major part of minor body population of the Solar System There are a lot of comets in the Solar System. (Oort cloud contains cometary 4 bodies which total mass is ~ 5 ME , ~10 higher than mass of the Main Asteroid Belt). Comets keep dynamical, mineralogical, chemical, and structural information that is critically important for understanding origin and early evolution of the Solar System. Comets are considered as important objects in the aspect of space threats and resources. Comets are intrinsically different from one another (A’Hearn+1995). 2 General comments on UV observations of comets Observations in the UV range are very informative, because this range contains the majority of аstrophysically significant resonance lines of atoms (OI, CI, HI, etc.), molecules (CO, CO2, OH etc.), and their ions. UV background is relatively low. UV imaging and spectroscopy are both widely used. In order to solve most of the problems, the UV data needs to be complemented observations in other ranges including ground-based observations. 3 First UV observations of comets from space Instruments Feeding Resolu Spectral range Comets Found optics tion Orbiting Astronomical 4x200mm ~10 Å 1100-2000 Å Bennett OH (1657 Å) Observatory (OAO-2) ~20 Å 2000-4000 Å С/1969 Y1 OI (1304 Å) 2 scanning spectrophotometers Launched in 1968 Orbiting Geophysical ~100cm2 Bennett Lyman-α Observatory (OGO-5) С/1969 Y1 halo Launched in 1968 Aerobee sounding D=50mm ~1 Å 1100-1800 Å Tago- Lyman-α halo rocket Sato- wide-angle all-reflective Kosaka spectrograph С/1969 Y1 Launched in 1970 Skylab 3 space station D=75mm Kohoutek Huge Lyman- Launched in 1973 С/1969 Y1 α halo NASA 990 Convair D=300mm Kohoutek OH (3090Å) aircraft. -
Activity and Composition of Comet Lulin
EPSC Abstracts, Vol. 4, EPSC2009-55, 2009 European Planetary Science Congress, © Author(s) 2009 Activity and composition of comet Lulin D. Bodewits (1,2), G.L. Villanueva (2,3), M.J. Mumma (2), W. Landsman(4), J. A. Carter (5) and A. M. Read (5) (1) NASA Postdoctoral Fellow, [email protected], (2) NASA GSFC, Solar System Exploration Divison, Greenbelt MD 20771, USA, (3) Dept. of Physics, The Catholic University of America, Washington, D. C., USA, (4) NASA GSFC, Astrophysics Science Divison, Greenbelt MD 20771 (5) Department of Physics and Astronomy, University of Leicester, Leicester LE1 1RH, UK Abstract The abundance of native ices in comet nuclei is a fundamental observational constraint in cosmogony. An important unresolved question is the extent to which the composition of pre- cometary ices varied with distance from the young sun. Our fundamental objective is to build a taxonomy based on cometary volatile composition instead of orbital dynamics [1]. The Swift space telescope [2] is unique in combining gamma ray, UV and X-ray instruments. Swift’s UV-optical grisms (175-520 nm), which have not been extensively used before this campaign, encompass known cometary + fluorescence bands (e.g., CO2 , OH, CO, NH, CS, CN, etc.) that can quantify and track the water and organic ice chemistry in the coma (see Figure 1). Until the scheduled repairs of HST’s STIS, Swift is the sole space-borne observatory that can characterize the molecular composition of a comet at UV-optical wavelengths. Through its rapid cadence, Swift is perfectly suited to characterize changes in the temporal development and composition of released gas. -
The GALEX Comets
15.11: The GALEX Comets J. P. Morgenthaler, W. M. Harris, M. R. Combi, P. D. Feldman, and H. A. Weaver October 2009 DPS Meeting Abstract The Galaxy Evolution Explorer (GALEX) has observed 6 comets since 2005 (C/2004 Q2 (Machholz), 9P/Tempel 1, 73P/Schwassmann-Wachmann 3 Fragments B and C, 8P/Tuttle and C/2007 N3 (Lulin). GALEX is a NASA Small Explorer (SMEX) mission designed to map the history of star forma- tion in the Universe. It is also well suited to cometary coma studies because ◦ of its high sensitivity and large field of view (1.2 ). OH and CS in the NUV (1750 – 3100 A)˚ are clearly detected in all of the comet data. The FUV (1340 – 1790 A)˚ channel recorded data during three of the comet observations and detects the bright C I 1561 and 1657 A˚ multiplets. We also see evidence + of S I 1475 A˚ in the FUV. NEW: we clearly detect CO emission in the NUV and CO Fourth positive emission in the FUV. The GALEX data were recorded with photon counting detectors, so it has been possible to reconstruct direct-mode and objective grism images in the reference frame of the comet. We have also created software which maps coma models onto the GALEX grism images for comparison to the data. We will present the data cleaned with automated catalog-based methods and a preliminary hand-fit to the data using simple Haser-based models. A more thorough hand-cleaning of the data from the contaminating effects of background sources is the last major reduction task to be done. -
Comet C/2011 J2 (LINEAR) Nucleus Splitting: Dynamical and Structural Analysis
Planetary and Space Science 126 (2016) 8–23 Contents lists available at ScienceDirect Planetary and Space Science journal homepage: www.elsevier.com/locate/pss Comet C/2011 J2 (LINEAR) nucleus splitting: Dynamical and structural analysis Federico Manzini a,b,n, Virginio Oldani a,b, Masatoshi Hirabayashi c, Raoul Behrend d, Roberto Crippa a,b, Paolo Ochner e, José Pablo Navarro Pina f, Roberto Haver g, Alexander Baransky h, Eric Bryssinck i, Andras Dan a,b, Josè De Queiroz j, Eric Frappa k, Maylis Lavayssiere l a Stazione Astronomica – Stazione Astronomica di Sozzago, 28060 Sozzago, Italy b FOAM13, Osservatorio di Tradate, Tradate, Italy c Earth, Atmospheric and Planetary Science, Purdue University, West Lafayette, IN 47907-2051, USA d Geneva Observatory, Geneva, Switzerland e INAF Astronomical Observatory of Padova, Italy f Asociacion Astronomica de Mula, Murcia, Spain g Osservatorio di Frasso Sabino, Italy h Astronomical Observatory of Kyiv University, Ukraine i BRIXIIS Observatory, Kruibeke, Belgium j Sternwarte Mirasteilas, Falera, Switzerland k Saint-Etienne Planetarium, France l Observatoire de Dax, France article info abstract Article history: After the discovery of the breakup event of comet C/2011 J2 in August 2014, we followed the primary Received 7 February 2016 body and the main fragment B for about 120 days in the context of a wide international collaboration. Received in revised form From the analysis of all published magnitude estimates we calculated the comet's absolute magni- 24 March 2016 tude H¼10.4, and its photometric index n¼1.7. We also calculated a water production of only 110 kg/s at Accepted 18 April 2016 the perihelion.