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Chapter 2: Earth in Space
Chapter 2: Earth in Space 1. Old Ideas, New Ideas 2. Origin of the Universe 3. Stars and Planets 4. Our Solar System 5. Earth, the Sun, and the Seasons 6. The Unique Composition of Earth Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Earth in Space Concept Survey Explain how we are influenced by Earth’s position in space on a daily basis. The Good Earth, Chapter 2: Earth in Space Old Ideas, New Ideas • Why is Earth the only planet known to support life? • How have our views of Earth’s position in space changed over time? • Why is it warmer in summer and colder in winter? (or, How does Earth’s position relative to the sun control the “Earthrise” taken by astronauts aboard Apollo 8, December 1968 climate?) The Good Earth, Chapter 2: Earth in Space Old Ideas, New Ideas From a Geocentric to Heliocentric System sun • Geocentric orbit hypothesis - Ancient civilizations interpreted rising of sun in east and setting in west to indicate the sun (and other planets) revolved around Earth Earth pictured at the center of a – Remained dominant geocentric planetary system idea for more than 2,000 years The Good Earth, Chapter 2: Earth in Space Old Ideas, New Ideas From a Geocentric to Heliocentric System • Heliocentric orbit hypothesis –16th century idea suggested by Copernicus • Confirmed by Galileo’s early 17th century observations of the phases of Venus – Changes in the size and shape of Venus as observed from Earth The Good Earth, Chapter 2: Earth in Space Old Ideas, New Ideas From a Geocentric to Heliocentric System • Galileo used early telescopes to observe changes in the size and shape of Venus as it revolved around the sun The Good Earth, Chapter 2: Earth in Space Earth in Space Conceptest The moon has what type of orbit? A. -
Luminosity - Wikipedia
12/2/2018 Luminosity - Wikipedia Luminosity In astronomy, luminosity is the total amount of energy emitted by a star, galaxy, or other astronomical object per unit time.[1] It is related to the brightness, which is the luminosity of an object in a given spectral region.[1] In SI units luminosity is measured in joules per second or watts. Values for luminosity are often given in the terms of the luminosity of the Sun, L⊙. Luminosity can also be given in terms of magnitude: the absolute bolometric magnitude (Mbol) of an object is a logarithmic measure of its total energy emission rate. Contents Measuring luminosity Stellar luminosity Image of galaxy NGC 4945 showing Radio luminosity the huge luminosity of the central few star clusters, suggesting there is an Magnitude AGN located in the center of the Luminosity formulae galaxy. Magnitude formulae See also References Further reading External links Measuring luminosity In astronomy, luminosity is the amount of electromagnetic energy a body radiates per unit of time.[2] When not qualified, the term "luminosity" means bolometric luminosity, which is measured either in the SI units, watts, or in terms of solar luminosities (L☉). A bolometer is the instrument used to measure radiant energy over a wide band by absorption and measurement of heating. A star also radiates neutrinos, which carry off some energy (about 2% in the case of our Sun), contributing to the star's total luminosity.[3] The IAU has defined a nominal solar luminosity of 3.828 × 102 6 W to promote publication of consistent and comparable values in units of https://en.wikipedia.org/wiki/Luminosity 1/9 12/2/2018 Luminosity - Wikipedia the solar luminosity.[4] While bolometers do exist, they cannot be used to measure even the apparent brightness of a star because they are insufficiently sensitive across the electromagnetic spectrum and because most wavelengths do not reach the surface of the Earth. -
The Future Life Span of Earth's Oxygenated Atmosphere
In press at Nature Geoscience The future life span of Earth’s oxygenated atmosphere Kazumi Ozaki1,2* and Christopher T. Reinhard2,3,4 1Department of Environmental Science, Toho University, Funabashi, Chiba 274-8510, Japan 2NASA Nexus for Exoplanet System Science (NExSS) 3School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA 4NASA Astrobiology Institute, Alternative Earths Team, Riverside, CA, USA *Correspondence to: [email protected] Abstract: Earth’s modern atmosphere is highly oxygenated and is a remotely detectable signal of its surface biosphere. However, the lifespan of oxygen-based biosignatures in Earth’s atmosphere remains uncertain, particularly for the distant future. Here we use a combined biogeochemistry and climate model to examine the likely timescale of oxygen-rich atmospheric conditions on Earth. Using a stochastic approach, we find that the mean future lifespan of Earth’s atmosphere, with oxygen levels more than 1% of the present atmospheric level, is 1.08 ± 0.14 billion years (1σ). The model projects that a deoxygenation of the atmosphere, with atmospheric O2 dropping sharply to levels reminiscent of the Archaean Earth, will most probably be triggered before the inception of moist greenhouse conditions in Earth’s climate system and before the extensive loss of surface water from the atmosphere. We find that future deoxygenation is an inevitable consequence of increasing solar fluxes, whereas its precise timing is modulated by the exchange flux of reducing power between the mantle and the ocean– atmosphere–crust system. Our results suggest that the planetary carbonate–silicate cycle will tend to lead to terminally CO2-limited biospheres and rapid atmospheric deoxygenation, emphasizing the need for robust atmospheric biosignatures applicable to weakly oxygenated and anoxic exoplanet atmospheres and highlighting the potential importance of atmospheric organic haze during the terminal stages of planetary habitability. -
Educator's Guide: Orion
Legends of the Night Sky Orion Educator’s Guide Grades K - 8 Written By: Dr. Phil Wymer, Ph.D. & Art Klinger Legends of the Night Sky: Orion Educator’s Guide Table of Contents Introduction………………………………………………………………....3 Constellations; General Overview……………………………………..4 Orion…………………………………………………………………………..22 Scorpius……………………………………………………………………….36 Canis Major…………………………………………………………………..45 Canis Minor…………………………………………………………………..52 Lesson Plans………………………………………………………………….56 Coloring Book…………………………………………………………………….….57 Hand Angles……………………………………………………………………….…64 Constellation Research..…………………………………………………….……71 When and Where to View Orion…………………………………….……..…77 Angles For Locating Orion..…………………………………………...……….78 Overhead Projector Punch Out of Orion……………………………………82 Where on Earth is: Thrace, Lemnos, and Crete?.............................83 Appendix………………………………………………………………………86 Copyright©2003, Audio Visual Imagineering, Inc. 2 Legends of the Night Sky: Orion Educator’s Guide Introduction It is our belief that “Legends of the Night sky: Orion” is the best multi-grade (K – 8), multi-disciplinary education package on the market today. It consists of a humorous 24-minute show and educator’s package. The Orion Educator’s Guide is designed for Planetarians, Teachers, and parents. The information is researched, organized, and laid out so that the educator need not spend hours coming up with lesson plans or labs. This has already been accomplished by certified educators. The guide is written to alleviate the fear of space and the night sky (that many elementary and middle school teachers have) when it comes to that section of the science lesson plan. It is an excellent tool that allows the parents to be a part of the learning experience. The guide is devised in such a way that there are plenty of visuals to assist the educator and student in finding the Winter constellations. -
On the Detection of Exoplanets Via Radial Velocity Doppler Spectroscopy
The Downtown Review Volume 1 Issue 1 Article 6 January 2015 On the Detection of Exoplanets via Radial Velocity Doppler Spectroscopy Joseph P. Glaser Cleveland State University Follow this and additional works at: https://engagedscholarship.csuohio.edu/tdr Part of the Astrophysics and Astronomy Commons How does access to this work benefit ou?y Let us know! Recommended Citation Glaser, Joseph P.. "On the Detection of Exoplanets via Radial Velocity Doppler Spectroscopy." The Downtown Review. Vol. 1. Iss. 1 (2015) . Available at: https://engagedscholarship.csuohio.edu/tdr/vol1/iss1/6 This Article is brought to you for free and open access by the Student Scholarship at EngagedScholarship@CSU. It has been accepted for inclusion in The Downtown Review by an authorized editor of EngagedScholarship@CSU. For more information, please contact [email protected]. Glaser: Detection of Exoplanets 1 Introduction to Exoplanets For centuries, some of humanity’s greatest minds have pondered over the possibility of other worlds orbiting the uncountable number of stars that exist in the visible universe. The seeds for eventual scientific speculation on the possibility of these "exoplanets" began with the works of a 16th century philosopher, Giordano Bruno. In his modernly celebrated work, On the Infinite Universe & Worlds, Bruno states: "This space we declare to be infinite (...) In it are an infinity of worlds of the same kind as our own." By the time of the European Scientific Revolution, Isaac Newton grew fond of the idea and wrote in his Principia: "If the fixed stars are the centers of similar systems [when compared to the solar system], they will all be constructed according to a similar design and subject to the dominion of One." Due to limitations on observational equipment, the field of exoplanetary systems existed primarily in theory until the late 1980s. -
Analysis of Planetary and Solar-Induced Perturbations on Trans-Martian Trajectory of Mars Missions Before and After Mars Orbit Insertion
Analysis of planetary and solar-induced perturbations on trans-Martian trajectory of Mars missions before and after Mars orbit insertion V U J Nwankwo1 and S K Chakrabarti1,2* 1S N Bose National Centre for Basic Sciences, Kolkata 700 098, West Bengal, India 2Indian Center for Space Physics, Kolkata 700 084, West Bengal, India Abstract: Interplanetary missions are susceptible to gravitational and nongravitational perturbing forces at every tra- jectory phase, assuming, of course, that the man made rockets and thrusters work as expected. These forces are mainly due to planetary and solar-forcing-induced perturbations during geocentric, heliocentric and Martian trajectories, and before orbit insertion. In this study, we review and/or analyze Mars orbiters mission associated perturbing forces and their possible impacts before Mars Orbit Insertion viz Earth’s oblateness, Third body (solar and lunar), solar radiation pressure, solar energetic radiation environment and atmospheric drag forces. We also model the significance of atmospheric drag force on Mangalyaan Mars orbiter mission, as a function of appropriate space environmental parameters during its 28 days in Earth’s orbit (around and during perigee passage), 300 days of heliocentric and 100 days of Martian trajectory. We have found that for a total perigee height boost of about 250 km, the cumulative orbit decay can be approximately 720 m. The approximate altitude variation could be up to 158 m with respect to the sun during 300 days of interplanetary journey toward Mars. After Mars orbit insertion, the total decay experienced by the spacecraft could be up to 701 m with decay rate of up to 9 m/day during 100 days of Martian trajectory, based on Mars–Earth atmosphere density ratio. -
Eleventh Annual Conference Chicago, Illinois 2005 August 18 – 21 John F
North American Sundial Society - Eleventh Annual Conference Chicago, Illinois 2005 August 18 – 21 John F. Schilke Who would not enjoy the mystique and appeal of free copies of Proceedings [of the] ISAMA CTI 2004, Chicago, that huge city on the shore of Lake Michigan? produced for a symposium on mathematics and design The architectural variety has to be seen to be held at DePaul. Among the door prize winners were appreciated. True, the weather was hot and sticky at Dwight Carpenter (several things, including a peg dial the first, but it soon settled into very pleasant summer and dial coins), Donn McNealy (Plymouth equatorial days and nights. DePaul University CTI Center sundial), Carl Schneider (a copy of Mike Cowham’s A provided a very comfortable setting for the thirty-four Dial in Your Poke), Dean Conners (A. P. Herbert’s people who attended the sessions. Fourteen wives and Sundials Old and New). A copy of Frank Cousins’ one care-giver, all hailing from 13 states and a total of Sundials became Walter Sanford’s prize, and Jacque 13 from Argentina, Canada, Germany, Taiwan, and the Olin and Karl Schneider each received a copy of Simon United Kingdom. During the conference several wives Wheaton-Smith’s Illustrating Shadows. took tours of Chicago and of the Chicago Art Museum with its special exhibition on Toulouse-Lautrec. Roger Bailey then showed how to program the programmable scientific calculator included in each registration packet. In doing so, he provided solutions to some of the equations useful in creating dials. Most actually got them to work! After a continental breakfast on Friday we boarded the bus to visit first the Museum of Science and Industry to see dials in their collection, including a fine example of a first-century (AD) dial, adjudged to be a slight variant of a hemisphaerium. -
Sulfur Hazes in Giant Exoplanet Atmospheres: Impacts on Reflected
Draft version February 28, 2017 Preprint typeset using LATEX style AASTeX6 v. 1.0 SULFUR HAZES IN GIANT EXOPLANET ATMOSPHERES: IMPACTS ON REFLECTED LIGHT SPECTRA Peter Gao1,2,3, Mark S. Marley, and Kevin Zahnle NASA Ames Research Center Moffett Field, CA 94035, USA Tyler D. Robinson4,5 Department of Astronomy and Astrophysics University of California Santa Cruz Santa Cruz, CA 95064, USA Nikole K. Lewis Space Telescope Science Institute Baltimore, MD 21218, USA 1Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA 2NASA Postdoctoral Program Fellow [email protected] 4Sagan Fellow 5NASA Astrobiology Institute’s Virtual Planetary Laboratory ABSTRACT Recent work has shown that sulfur hazes may arise in the atmospheres of some giant exoplanets due to the photolysis of H2S. We investigate the impact such a haze would have on an exoplanet’s geometric albedo spectrum and how it may affect the direct imaging results of WFIRST, a planned NASA space telescope. For temperate (250 K < Teq < 700 K) Jupiter–mass planets, photochemical destruction of H2S results in the production of 1 ppmv of S8 between 100 and 0.1 mbar, which, if cool enough, ∼ will condense to form a haze. Nominal haze masses are found to drastically alter a planet’s geometric albedo spectrum: whereas a clear atmosphere is dark at wavelengths between 0.5 and 1 µm due to molecular absorption, the addition of a sulfur haze boosts the albedo there to 0.7 due to scattering. ∼ Strong absorption by the haze shortward of 0.4 µm results in albedos <0.1, in contrast to the high albedos produced by Rayleigh scattering in a clear atmosphere. -
2021 Science Olympiad National Tournament Tournament Schedule & Event Blocks
2021 Science Olympiad National Tournament Tournament Schedule & Event Blocks 2021 Science Olympiad National Tournament Competition Schedule Mountain Pacific Alaska Hawaii Event Block Eastern Time Central Time Time Time Time Time Block 1 11:00 AM 10:00 AM 9:00 AM 8:00 AM Block 2 12:10 PM 11:10 AM 10:10 AM 9:10 AM 8:10 AM Block 3 1:20 PM 12:20 PM 11:20 AM 10:20 AM 9:20 AM Block 4 2:30 PM 1:30 PM 12:30 PM 11:30 AM 10:30 AM 8:30 AM STEM Showdown 3:00 PM 2:00 PM 1:00 PM 12:00 PM 11:00 AM 9:00 AM Trial Events Block 5 3:40 PM 2:40 PM 1:40 PM 12:40 PM 11:40 AM 9:40 AM Block 6 4:50 PM 3:50 PM 2:50 PM 1:50 PM 12:50 PM 10:50 AM Block 7 2:00 PM 12:00 PM Block 8 1:10 PM Block 9 2:20 PM The 2021 Science Olympiad Tournament will start across the United States at the times shown above. The times listed above reflect the local time in that Time Zone on May 22, 2021. Each Event Block will run for one hour and be followed by a 10- minute Break before the next Event Block begins. No team will begin the competition prior to 8:00 AM local time. Teams from Alaska and Hawaii will join the tournament in progress and complete any Event Blocks missed at the end of their day. -
Cosmos: a Spacetime Odyssey (2014) Episode Scripts Based On
Cosmos: A SpaceTime Odyssey (2014) Episode Scripts Based on Cosmos: A Personal Voyage by Carl Sagan, Ann Druyan & Steven Soter Directed by Brannon Braga, Bill Pope & Ann Druyan Presented by Neil deGrasse Tyson Composer(s) Alan Silvestri Country of origin United States Original language(s) English No. of episodes 13 (List of episodes) 1 - Standing Up in the Milky Way 2 - Some of the Things That Molecules Do 3 - When Knowledge Conquered Fear 4 - A Sky Full of Ghosts 5 - Hiding In The Light 6 - Deeper, Deeper, Deeper Still 7 - The Clean Room 8 - Sisters of the Sun 9 - The Lost Worlds of Planet Earth 10 - The Electric Boy 11 - The Immortals 12 - The World Set Free 13 - Unafraid Of The Dark 1 - Standing Up in the Milky Way The cosmos is all there is, or ever was, or ever will be. Come with me. A generation ago, the astronomer Carl Sagan stood here and launched hundreds of millions of us on a great adventure: the exploration of the universe revealed by science. It's time to get going again. We're about to begin a journey that will take us from the infinitesimal to the infinite, from the dawn of time to the distant future. We'll explore galaxies and suns and worlds, surf the gravity waves of space-time, encounter beings that live in fire and ice, explore the planets of stars that never die, discover atoms as massive as suns and universes smaller than atoms. Cosmos is also a story about us. It's the saga of how wandering bands of hunters and gatherers found their way to the stars, one adventure with many heroes. -
Variable Star Classification and Light Curves Manual
Variable Star Classification and Light Curves An AAVSO course for the Carolyn Hurless Online Institute for Continuing Education in Astronomy (CHOICE) This is copyrighted material meant only for official enrollees in this online course. Do not share this document with others. Please do not quote from it without prior permission from the AAVSO. Table of Contents Course Description and Requirements for Completion Chapter One- 1. Introduction . What are variable stars? . The first known variable stars 2. Variable Star Names . Constellation names . Greek letters (Bayer letters) . GCVS naming scheme . Other naming conventions . Naming variable star types 3. The Main Types of variability Extrinsic . Eclipsing . Rotating . Microlensing Intrinsic . Pulsating . Eruptive . Cataclysmic . X-Ray 4. The Variability Tree Chapter Two- 1. Rotating Variables . The Sun . BY Dra stars . RS CVn stars . Rotating ellipsoidal variables 2. Eclipsing Variables . EA . EB . EW . EP . Roche Lobes 1 Chapter Three- 1. Pulsating Variables . Classical Cepheids . Type II Cepheids . RV Tau stars . Delta Sct stars . RR Lyr stars . Miras . Semi-regular stars 2. Eruptive Variables . Young Stellar Objects . T Tau stars . FUOrs . EXOrs . UXOrs . UV Cet stars . Gamma Cas stars . S Dor stars . R CrB stars Chapter Four- 1. Cataclysmic Variables . Dwarf Novae . Novae . Recurrent Novae . Magnetic CVs . Symbiotic Variables . Supernovae 2. Other Variables . Gamma-Ray Bursters . Active Galactic Nuclei 2 Course Description and Requirements for Completion This course is an overview of the types of variable stars most commonly observed by AAVSO observers. We discuss the physical processes behind what makes each type variable and how this is demonstrated in their light curves. Variable star names and nomenclature are placed in a historical context to aid in understanding today’s classification scheme. -
1999-2000 Annual Report
Anglo-Australian Observatory Annual Report of the Anglo-Australian Telescope Board 1 July 1999 to 30 June 2000 ANGLO-AUSTRALIAN OBSERVATORY PO Box 296, Epping, NSW 1710, Australia 167 Vimiera Road, Eastwood, NSW 2122, Australia PH (02) 9372 4800 (international) + 61 2 9372 4800 FAX (02) 9372 4880 (international) + 61 2 9372 4880 e-mail [email protected] ANGLO-AUSTRALIAN TELESCOPE BOARD PO Box 296, Epping, NSW 1710, Australia 167 Vimiera Road, Eastwood, NSW 2122, Australia PH (02) 9372 4813 (international) + 61 2 9372 4813 FAX (02) 9372 4880 (international) + 61 2 9372 4880 e-mail [email protected] ANGLO-AUSTRALIAN TELESCOPE/UK SCHMIDT TELESCOPE PriVate Bag, Coonabarabran, NSW 2357, Australia PH (02) 6842 6291 (international) + 61 2 6842 6291 AAT FAX (02) 6884 2298 (international) + 61 2 6884 298 UKST FAX (02) 6842 2288 (international) + 61 2 6842 2288 WWW http://www.aao.gov.au/ © Anglo-Australian Telescope Board 2000 ISSN 1443-8550 COVER: A digital image of the Antennae galaxies (NGC4038-39) made by combining three images from the Tek2 CCD on the AAT (Steve Lee and David Malin). A new wide field CCD Imager (WFI) will come into use in 2000 and will enable many more images like this to be made. COVER DESIGN: Encore International COMPUTER TYPESET AT THE: Anglo-Australian ObserVatory ii The Right Honourable Stephen Byers, MP, President of the Board of Trade and Secretary of State for Trade and Industry, Government of the United Kingdom of Great Britain and Northern Ireland The Honourable Dr David Kemp, MP, Minister for Education, Training and Youth Affairs GoVernment of the Commonwealth of Australia In accordance with Article 8 of the Agreement between the Australian GoVernment and the GoVernment of the United Kingdom to proVide for the establishment and operation of an optical telescope at Siding Spring Mountain in the state of New South Wales, I present herewith a report by the Anglo-Australian Telescope Board for the year from 1 July 1999 to 30 June 2000.