Solar and Lunar Eclipses the Great Eclipse
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Advances in the Interpretation and Analysis of Lunar Occultation Light Curves
A&A 538, A56 (2012) Astronomy DOI: 10.1051/0004-6361/201118476 & c ESO 2012 Astrophysics Advances in the interpretation and analysis of lunar occultation light curves A. Richichi1,2 and A. Glindemann2 1 National Astronomical Research Institute of Thailand, 191 Siriphanich Bldg., Huay Kaew Rd., Suthep, Muang, Chiang Mai 50200, Thailand e-mail: [email protected] 2 European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching bei München, Germany Received 18 November 2011 / Accepted 23 December 2011 ABSTRACT Context. The introduction of fast 2D detectors and the use of very large telescopes have significantly advanced the sensitivity and accuracy of the lunar occultation technique. Recent routine observations at the ESO Very Large Telescope have yielded hundreds of events with results, especially in the area of binary stars, which are often beyond the capabilities of any other techniques. Aims. With the increase in the quality and in the number of the events, subtle features in the light curve patterns have occasionally been detected which challenge the standard analytical definition of the lunar occultation phenomenon as diffraction from an infinite straight edge. We investigate the possible causes for the observed peculiarities. Methods. We have evaluated the available statistics of distortions in occultation light curves observed at the ESO VLT, and compared it to data from other facilities. We have developed an alternative approach to model and interpret lunar occultation light curves, based on 2D diffraction integrals describing the light curves in the presence of an arbitrary lunar limb profile. We distinguish between large limb irregularities requiring the Fresnel diffraction formalism, and small irregularities described by Fraunhofer diffraction. -
Journal Issue 26 | October 2019
journal Issue 26 | October 2019 Communicating Astronomy with the Public Spotlighting a Black Hole What did it take to create the largest outreach campaign for an astronomical result? Tactile Subaru A project to make telescope technology accessible Naming ExoWorlds Update on the IAU100 NameExoWorlds campaign www.capjournal.org As part of the 100th anniversary commemorations, the International Astronomical Union (IAU) is organising the IAU100 NameExoWorlds global competition to allow any country in the world to give a popular name to a selected exoplanet and its News News host star. The final results of the competion will be announced in Decmeber 2019. Credit: IAU/L. Calçada. Editorial Welcome to the 26th edition of the CAPjournal! To start off, the first part of 2019 brought in a radical new era in astronomy with the first ever image showing a shadow of a black hole. For CAPjournal #26, part of the team who collaborated on the promotion of this image hs written a piece to show what it took to produce one of the largest astronomy outreach campaigns to date. We also highlight two other large outreach campaigns in this edition. The first is a peer-reviewed article about the 2016 solar eclipse in Indonesia from the founder of the astronomy website lagiselatan, Avivah Yamani. Next, an update on NameExoWorlds, the largest IAU100 campaign, as we wait for the announcement of new names for the ExoWorlds in December. Additionally, this issue touches on opportunities for more inclusive astronomy. We bring you a peer-reviewed article about outreach for inclusion by Dr. Kumiko Usuda-Sato and the speech “Diversity Across Astronomy Can Further Our Research” delivered by award-winning astronomy communicator Dr. -
University Microfilms, a XEROX Company, Ann Arbor, Michigan
.72-4480 FAJEMIROKUN, Francis Afolabi, 1941- APPLICATION OF NEW OBSERVATIONAL SYSTEMS FOR SELENODETIC CONTROL. The Ohio State University, Ph.D., 1971 Geodesy University Microfilms, A XEROX Company, Ann Arbor, Michigan THIS DISSERTATION HAS BEEN MICROFILMED EXACTLY AS RECEIVED APPLICATION OF NEW OBSERVATIONAL SYSTEMS FOR SELENODETIC CONTROL DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University by Francis Afolabi Fajemirokun, B. Sc., M. Sc. The Ohio State University 1971 Approved by l/m /• A dviser Department of Geodetic Science PLEASE NOTE: Some Pages have indistinct p rin t. Filmed as received. UNIVERSITY MICROFILMS To Ijigbola, Ibeolayemi and Oladunni ACKNOW LEDGEME NTS The author wishes to express his deep gratitude to the many persons, without whom this work would not have been possible. First and foremost, the author is grateful to the Department of Geodetic Science and themembers of its staff, for the financial support and academic guidance given to him during his studies here. In particular, the author wishes to thank his adviser Professor Ivan I. Mueller, for his encouragement, patience and guidance through the various stages of this work. Professors Urho A. Uotila, Richard H. Rapp and Gerald H. Newsom served on the author’s reading committee, and offered many valuable suggestions to help clarify many points. The author has also enjoyed working with other graduate students in the department, especially with the group at 231 Lord Hall, where there was always an atmosphere of enthusiastic learning and of true friendship. The author is grateful to the various scientists outside the department, with whom he had discussions on the subject of this work, especially to the VLBI group at the Smithsonian Astrophysical Observatory in Cambridge, Ma s sachu s s etts . -
GCSE Astronomy Coursework
GCSE Astronomy Coursework A5 & B5 Drawings or Photos of Celestial Event Produce a series of drawings (A5) or detailed telescopic drawings or photographs (B5) to record the passage of a suitable celestial event, for example a transit, occultation or comet. Venus and Mercury are the two inferior planets (planets that orbit between the Earth and the Sun). Their orbits are slightly inclined with respect to the Earth’s orbital plane but sometimes they pass in between the Earth and the Sun – this is called a transit. Dates for the next set of transits can be found here: http://eclipse.gsfc.nasa.gov/transit/transit.html When an object is eclipsed by another object in the sky it is called an occultation. Information about future occultations and all other celestial events can be found here: www.theguardian.com/science/series/starwatch Comets are balls of ice and rock that exist in two regions in the outer Solar System: the Kuiper Belt and the Oort Cloud. Occasionally they are knocked and are sent flying past the planets. When they reach the Sun the ice sublimates leaving behind a tail. A list of visible comets can be found here: www.ast.cam.ac.uk/~jds/future.htm To locate objects use www.stellarium.org or alternatively download an app for your mobile: http://downloads.bbc.co.uk/tv/guides/ BBC_Stargazing_Live_2012_Mobile_App_guides.pdf To find sunrise, sunset, moonrise and moonset times and the phase of the Moon use www.timeanddate.com Check the weather forecast - www.metoffice.gov.uk See our useful guides for help on how to carry out observations and take photographs of various objects: www.rmg.co.uk/discover/astronomy- photographer-competition/how-to-guides For examples of reports with moderator comments visit the Edexcel GCSE Astronomy website: http://www.edexcel.com/quals/gcse/gcse09/ astronomy/Pages/default.aspx Here you will find two documents that will help you write a report: Under ‘Controlled assessment’ download ‘Controlled Assessment Teacher Support Book’ and under ‘Teacher Support Materials’ download ‘GCSE Astronomy Teachers Guide’. -
Water on the Moon, III. Volatiles & Activity
Water on The Moon, III. Volatiles & Activity Arlin Crotts (Columbia University) For centuries some scientists have argued that there is activity on the Moon (or water, as recounted in Parts I & II), while others have thought the Moon is simply a dead, inactive world. [1] The question comes in several forms: is there a detectable atmosphere? Does the surface of the Moon change? What causes interior seismic activity? From a more modern viewpoint, we now know that as much carbon monoxide as water was excavated during the LCROSS impact, as detailed in Part I, and a comparable amount of other volatiles were found. At one time the Moon outgassed prodigious amounts of water and hydrogen in volcanic fire fountains, but released similar amounts of volatile sulfur (or SO2), and presumably large amounts of carbon dioxide or monoxide, if theory is to be believed. So water on the Moon is associated with other gases. Astronomers have agreed for centuries that there is no firm evidence for “weather” on the Moon visible from Earth, and little evidence of thick atmosphere. [2] How would one detect the Moon’s atmosphere from Earth? An obvious means is atmospheric refraction. As you watch the Sun set, its image is displaced by Earth’s atmospheric refraction at the horizon from the position it would have if there were no atmosphere, by roughly 0.6 degree (a bit more than the Sun’s angular diameter). On the Moon, any atmosphere would cause an analogous effect for a star passing behind the Moon during an occultation (multiplied by two since the light travels both into and out of the lunar atmosphere). -
Glossary of Lunar Terminology
Glossary of Lunar Terminology albedo A measure of the reflectivity of the Moon's gabbro A coarse crystalline rock, often found in the visible surface. The Moon's albedo averages 0.07, which lunar highlands, containing plagioclase and pyroxene. means that its surface reflects, on average, 7% of the Anorthositic gabbros contain 65-78% calcium feldspar. light falling on it. gardening The process by which the Moon's surface is anorthosite A coarse-grained rock, largely composed of mixed with deeper layers, mainly as a result of meteor calcium feldspar, common on the Moon. itic bombardment. basalt A type of fine-grained volcanic rock containing ghost crater (ruined crater) The faint outline that remains the minerals pyroxene and plagioclase (calcium of a lunar crater that has been largely erased by some feldspar). Mare basalts are rich in iron and titanium, later action, usually lava flooding. while highland basalts are high in aluminum. glacis A gently sloping bank; an old term for the outer breccia A rock composed of a matrix oflarger, angular slope of a crater's walls. stony fragments and a finer, binding component. graben A sunken area between faults. caldera A type of volcanic crater formed primarily by a highlands The Moon's lighter-colored regions, which sinking of its floor rather than by the ejection of lava. are higher than their surroundings and thus not central peak A mountainous landform at or near the covered by dark lavas. Most highland features are the center of certain lunar craters, possibly formed by an rims or central peaks of impact sites. -
Highlight Events in Astronomy 2017 a Brief Look at the Year Ahead
Highlight events in Astronomy 2017 A brief look at the year ahead Vancouver, BC, January 1, 2017 – Conjunction of Mars, Venus, Moon: Jan 31st A conjunction marks one of the perfect viewing opportunities for people. A conjunction is when two or more objects appear close to each other in the night sky. On the 31st of January, Mars, Venus, and the moon will all be in the western sky, setting together. Watch for this spectacular and rare event right after sunset between the 29th and the 2nd, with the best opportunity on the 31st of January. You do not even need a telescope! Juno continues mission around Jupiter Juno arrived at Jupiter earlier in July of 2016, marking a historic feat in space exploration. Having a few minor hiccups in some of the tech on the craft, it has been working fantastically and has already helped us understand the largest planet in our solar system more. The mission continues and more and more data comes pouring in every day. The data has already surprised astronomers, and there is so much to still learn from this mission. Some of our major understandings of Jupiter are being altered because of the data from this mission. Lightsail 2 launches: March The Planetary Society has been pioneering a new way of space flight: riding along the waves of space using the Sun's energy as power. The Lightsail project is aiming to send their second prototype into space for deployment. Just like a sailboat, the Lightsail is pushed along by having a massive collection area where the light from the Sun pushes against the craft, slowly accelerating it. -
A Comparison of Astronomical Terminology and Concepts in China and Mesopotamia
A Comparison of Astronomical Terminology and Concepts in China and Mesopotamia J. M. Steele, University of Durham 1. Introduction An interest in the movement and appearance of the sun, moon, planets and stars can be traced back in contemporary written sources to at least the Old Babylonian period in Mesopotamia (first half of the second millennium BC) and to the Shang dynasty in China (mid to end of the second millennium BC). In Mesopotamia, Old Babylonian cuneiform tablets contain omens drawn from the appearance of lunar eclipses (Rochberg 2006) and schematic lists of the length of day and night throughout the year (Hunger and Pingree 1989, pp. 163–164). In China, references to astronomical phenomena such as eclipses and comets appear on the so-called ‘oracle bones’ (Xu, Yau and Stephenson 1989; Xu, Stephenson and Jiang 1995). Except for so-called ‘star-clocks’ and related astronomical material from ancient Egypt, no contemporary writings on astronomical subjects are known from other cultures this early. Although cuneiform texts containing astronomical material are preserved from all periods in the second and first millennium BC, material is very scarce until the Late Babylonian period (c. 750 BC to AD 100), with the vast majority of texts coming from the last four centuries BC. A similar situation holds for China: after the Shang dynasty oracle bones we only have a very few documents containing astronomical records (principally the Zhushujinian 竹書紀年 ‘The Bamboo Annals’ and the Chunqui 春秋 ‘The Spring and Autumn Annals’) until the second century BC. After this time we have an extensive and continuous tradition of astronomical writings contained within the 25 Zhengshi 正史, generally referred to in English as the ‘Dynastic Histories’, and many individual books on astronomical topics, down to modern times. -
User Manual Star Walk™ for Iphone/Ipod Touch/Ipad
User Manual Star Walk™ for iPhone/iPod Touch/iPad December 2013, ver. 7.0.3 for Android devices January 2014, ver. 1.0.1 2 Star Walk™ manual Table of Contents iOS version 4 1 Introduction 4 2 Getting started 5 2.1 Sky Live window 5 2.2 Location set up 6 2.3 Using/Activating Star Spotter 8 2.4 Augmented Reality 9 2.5 Spectrum Bar 9 2.6. Stargazing Community 9 2.7 Display/Interface 11 3 Menu 11 3.1 Day and Night color schemes 12 3.2 Constellations display 12 3.3 Satellites 13 3.4 TelRad 13 3.5 Playing sounds 13 3.6 Playing music 13 3.7 Magnitude adjustment 13 4 Using functions of Star Walk™ 13 4.1 Changing date and time 13 4.2 Getting information about an object 14 4.3 Searching for sky objects 14 4.4 Watching astronomical events 15 4.5 Using Astronomy Pictures 16 4.6 Posting pictures in Star Walk™ 17 4.7 Sharing 18 4.8 Watching moon phases 19 5 Star Walk™ on a big screen using cables 19 6 Star Walk™ on a big screen using AirPlay 20 7 The Apple Volume Purchase Program 20 FAQ 22 Glossary 23 Android version 26 1 Introduction 26 2 Getting started 26 3 Star Walk™ manual 2.1 Sky Live window 27 2.2 Location set up 27 2.3 Using/Activating Star Spotter 28 2.4 Augmented Reality 29 2.5 Spectrum Bar 30 2.6. Sharing 30 2.7 Display/Interface 30 3 Menu 32 3.1 Day and Night color schemes 32 3.2 Constellations display 32 3.3 Satellites 32 3.4 Playing sounds 33 3.5 Playing music 33 3.6 Magnitude adjustment 33 4 Using functions of Star Walk™ 33 4.1 Changing date and time 33 4.2 Getting information about an object 33 4.4 Sharing 35 4.5 Watching moon phases 35 FAQ 36 Glossary 37 4 Star Walk™ manual iOS version 1 Introduction Star Walk™ is a stargazing application for amateurs, professionals, and kids who are eager to learn. -
Arxiv:2107.09416V1
Draft version July 21, 2021 A Typeset using L TEX twocolumn style in AASTeX631 Estimation of the Eclipse Solar Radius by Flash Spectrum Video Analysis Luca Quaglia,1 John Irwin,2 Konstantinos Emmanouilidis,3 and Alessandro Pessi4 1Sydney, New South Wales, Australia 2Guildford, England, United Kingdom 3Thessaloniki, Greece 4Milan, Italy ABSTRACT The value of the eclipse solar radius during the 2017 August 21st total solar eclipse was estimated to be S⊙ = (959.95±0.05)”at 1 au with no significant dependence on wavelength. The measurement was obtained from the analysis of a video of the eclipse flash spectrum recorded at the southern limit of the umbral shadow path. Our analysis was conducted by extracting light curves from the flash spectrum and comparing them to simulated light curves. Simulations were performed by integrating the limb darkening function (LDF) over the exposed area of photosphere. These numerical integrations relied upon very precise computations of the relative movement of the lunar and solar limbs. Keywords: Solar radius (1488) — Solar eclipses (1489) — Flash spectrum (541) — Light curves (918) — Astronomical simulations (1857) 1. INTRODUCTION rameters is now below the milliarcsecond level while the accuracy of UT1 determination is well below the mil- The value of the solar radius at unit distance S⊙ is one of the fundamental quantities needed to perform very lisecond level. Satellite missions in the last decade have precise eclipse computations. Some of the other required vastly improved the knowledge of the topography of the inputs are: accurate ephemerides for the position of the Moon (Smith et al. 2017) to better than 10 m (corre- centres of mass of the Sun and Moon; accurate models sponding to about 5 mas at the mean geocentric dis- for the orientation of the Earth and Moon; and detailed tance of the Moon), allowing accurate computations of data on the topography of the Moon and Earth. -
INTERAGENCY REPORT: ASTROGEOLOGY 7 ADVANCED SYSTEMS TRAVERSE RESEARCH PROJECT REPORT by G
INTERAGENCY REPORT: ASTROGEOLOGY 7 ADVANCED SYSTEMS TRAVERSE RESEARCH PROJECT REPORT By G. E. Ulrich With a Section on Problems for Geologic Investigations of the Orientale Region of the Moon By R. S. Saunders July 1968 CONTENTS Page Abs tract . ............. 1 Introduct ion . •• # • ••• ••• .' • 2 Physiographic subdivision of the lunar surface 3 Site selection and preliminary traverse research. 8 Lunar topographic data •••••••.•.•••••• 17 Objectives and evaluation of traverse concepts • 20 Recommendations for continued traverse research .••• 26 Problems for geologic investigations of the Orientale region of the Moon, by R. S. Saunders 30 Introduct ion •.•• •••. 30 Physiography 30 Pre-Orbiter observations and i~terpretations 35 Geologic interpretations based on Orbiter photography ••••••••• 38 Conelusions •••• .•••. 54 References 56 ILLUSTRATIONS Figure 1. Map and index to photographs of Orientale basin region ••••.•••••• 4 2. Crater-size frequency distributions of Orientale basin terrain units •••••• 11 3. Orientale basin region showing pre- liminary traverse evaluation areas ••••• 14 4. Effect of photographic exposure on shadow measurements 15 5. Alternate traverse areas for short and intermediate duration missions. North eastern sector of central Orientale basin ................... 24 6. Preliminary photogeologic map of the Orientale basin region. .•• .. .. 32 iii Page Figure 7. Sketch map of Mare Orientale region prepared from Earth-based telescopic photography • 36 8-21. Orbiter IV photographs of Orientale basin region showing-- . 8. Part of wr{nk1e ridge . 41 9. Slump scarps around steptoe and collapse depression . 44 10. Slump scarps along margin of central mare basin outlining collapse depression • • . • 44 11. Possible caldera 45 12. Northeast quadrant of inner ring showing central basin material and mare units 45 13. -
Eclipse Observations Enabled by NASA's Lunar Reconnaissance
National Aeronautics and Space Administration Eclipse Observations enabled by NASA’s Lunar Reconnaissance Orbiter Eclipse Observations enabled by NASA’s Lunar Reconnaissance Orbiter Data from NASA’s Lunar Reconnaissance Orbiter (LRO) is revolutionizing our understanding of the Moon. With LRO, we have found evidence of recent lunar volcanism. Some lava may have erupted onto the Moon’s surface only tens to hundreds of millions of years ago, instead of billions of years ago, as previously thought. We have found faults that indicate the entire Moon is shrinking! (Just a little bit, within the past few million years.) LRO has also witnessed changes on the Moon’s surface (including lots of new impact craters) since the mission began in 2009. Every day, this spacecraft is helping us better understand our nearest celestial neighbor, and processes that are occurring throughout the Solar System. You can learn more about these discoveries on LRO’s website, www.nasa.gov/lro. A B Thanks to LRO’s onboard laser altimeter and high-resolution cameras we know the shape of the Moon better than any other object in the Solar System – including Earth (since the majority of the Earth’s solid surface is under water). The top left image (A), shows the topography of the Moon, where cool colors represent low elevations and warm colors show areas with higher elevation. The blue line surrounding the Moon in the top right image (B) shows the outline of the Moon’s topographic profile, exaggerated 20 times. The bottom image shows an oblique view of the Orientale basin: an example of the rough topography found on the Moon.