Astrocalc4r: Software to Calculate Solar Zenith Angle
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DTA Scoring Form
Daytime Astronomy SHADOWS Score Form Date ____/____/____ Student _______________________________________ Rater _________________ Problem I. (Page 3) Accuracy of results Draw a dot on this map to show where you think Tower C is. Tower C is in Eastern US Tower C is in North Eastern US Tower C is somewhere in between Pennsylvania and Maine Modeling/reasoning/observation How did you figure out where Tower C is? Matched shadow lengths of towers A and B/ pointed flashlight to Equator Tried different locations for tower C/ inferred location of tower C Matched length of shadow C/considered Latitude (distance from Equator) Matched angle of shadow C/ considered Longitude (East-West direction) Problem II. (Page 4) Accuracy of results How does the shadow of Tower A look at 10 AM and 3 PM?... Which direction is the shadow moving? 10 AM shadow points to NNW 10 AM shadow is shorter than noon shadow 3 PM shadow points to NE 3 PM shadow is longer than noon shadow Clockwise motion of shadows Modeling/reasoning/observation How did you figure out what the shadow of Tower A looks like at 10 AM and 3 PM? Earth rotation/ "Sun motion" Sunlight coming from East projects a shadow oriented to West Sunlight coming from West projects a shadow oriented to East Sunlight coming from above us projects a shadow oriented to North Sun shadows are longer in the morning than at noon Morning Sun shadows become shorter and shorter until its noon The shortest Sun shadow is at noon Sun shadows are longer in the afternoon than at noon Afternoon Sun shadows become longer and longer until it gets dark (Over, please) - 1 - 6/95 Problem III. -
Final Report Venus Exploration Targets Workshop May 19–21
Final Report Venus Exploration Targets Workshop May 19–21, 2014, Lunar and Planetary Institute, Houston, TX Conveners: Virgil (Buck) Sharpton, Larry Esposito, Christophe Sotin Breakout Group Leads Science from the Surface Larry Esposito, Univ. Colorado Science from the Atmosphere Kevin McGouldrick, Univ. Colorado Science from Orbit Lori Glaze, GSFC Science Organizing Committee: Ben Bussey, Martha Gilmore, Lori Glaze, Robert Herrick, Stephanie Johnston, Christopher Lee, Kevin McGouldrick Vision: The intent of this “living” document is to identify scientifically important Venus targets, as the knowledge base for this planet progresses, and to develop a target database (i.e., scientific significance, priority, description, coordinates, etc.) that could serve as reference for future missions to Venus. This document will be posted in the VEXAG website (http://www.lpi.usra.edu/vexag/), and it will be revised after the completion of each Venus Exploration Targets Workshop. The point of contact for this document is the current VEXAG Chair listed at ABOUT US on the VEXAG website. Venus Exploration Targets Workshop Report 1 Contents Overview ....................................................................................................................................................... 2 1. Science on the Surface .............................................................................................................................. 3 2. Science within the Atmosphere ............................................................................................................... -
Exploring Solar Cycle Influences on Polar Plasma Convection
Comparison of Terrestrial and Martian TEC at Dawn and Dusk during Solstices Angeline G. Burrell1 Beatriz Sanchez-Cano2, Mark Lester2, Russell Stoneback1, Olivier Witasse3, Marco Cartacci4 1Center for Space Sciences, University of Texas at Dallas 2Radio and Space Plasma Physics, University of Leicester 3European Space Agency, ESTEC – Scientific Support Office 4Istituto Nazionale di Astrofisica, Istituto di Astrofisica e Planetologia Spaziali 52nd ESLAB Symposium Outline • Motivation • Data and analysis – TEC sources – Data selection – Linear fitting • Results – Martian variations – Terrestrial variations – Similarities and differences • Conclusions Motivation • The Earth and Mars are arguably the most similar of the solar planets - They are both inner, rocky planets - They have similar axial tilts - They both have ionospheres that are formed primarily through EUV and X- ray radiation • Planetary differences can provide physical insights Total Electron Content (TEC) • The Global Positioning System • The Mars Advanced Radar for (GPS) measures TEC globally Subsurface and Ionosphere using a network of satellites and Sounding (MARSIS) measures ground receivers the TEC between the Martian • MIT Haystack provides calibrated surface and Mars Express TEC measurements • Mars Express has an inclination - Available from 1999 onward of 86.9˚ and a period of 7h, - Includes all open ground and allowing observations of all space-based sources locations and times - Specified with a 1˚ latitude by 1˚ • TEC is available for solar zenith longitude resolution with error estimates angles (SZA) greater than 75˚ Picardi and Sorge (2000), In: Proc. SPIE. Eighth International Rideout and Coster (2006) doi:10.1007/s10291-006-0029-5, 2006. Conference on Ground Penetrating Radar, vol. 4084, pp. 624–629. -
Morphology and Dynamics of the Venus Atmosphere at the Cloud Top Level As Observed by the Venus Monitoring Camera
Morphology and dynamics of the Venus atmosphere at the cloud top level as observed by the Venus Monitoring Camera Von der Fakultät für Elektrotechnik, Informationstechnik, Physik der Technischen Universität Carolo-Wilhelmina zu Braunschweig zur Erlangung des Grades eines Doktors der Naturwissenschaften (Dr.rer.nat.) genehmigte Dissertation von Richard Moissl aus Grünstadt Bibliografische Information Der Deutschen Bibliothek Die Deutsche Bibliothek verzeichnet diese Publikation in der Deutschen Nationalbibliografie; detaillierte bibliografische Daten sind im Internet über http://dnb.ddb.de abrufbar. 1. Referentin oder Referent: Prof. Dr. Jürgen Blum 2. Referentin oder Referent: Dr. Horst-Uwe Keller eingereicht am: 24. April 2008 mündliche Prüfung (Disputation) am: 9. Juli 2008 ISBN 978-3-936586-86-2 Copernicus Publications, Katlenburg-Lindau Druck: Schaltungsdienst Lange, Berlin Printed in Germany Contents Summary 7 1 Introduction 9 1.1 Historical observations of Venus . .9 1.2 The atmosphere and climate of Venus . .9 1.2.1 Basic composition and structure of the Venus atmosphere . .9 1.2.2 The clouds of Venus . 11 1.2.3 Atmospheric dynamics at the cloud level . 12 1.3 Venus Express . 16 1.4 Goals and structure of the thesis . 19 2 The Venus Monitoring Camera experiment 21 2.1 Scientific objectives of the VMC in the context of this thesis . 21 2.1.1 UV Channel . 21 2.1.1.1 Morphology of the unknown UV absorber . 21 2.1.1.2 Atmospheric dynamics of the cloud tops . 21 2.1.2 The two IR channels . 22 2.1.2.1 Water vapor abundance and cloud opacity . 22 2.1.2.2 Surface and lower atmosphere . -
Solar Photovoltaic (PV) Site Assessment
Solar Photovoltaic (PV) Site Assessment Item Type text; Book Authors Franklin, Ed Publisher College of Agriculture, University of Arizona (Tucson, AZ) Download date 29/09/2021 11:10:49 Item License http://creativecommons.org/licenses/by-nc-sa/4.0/ Link to Item http://hdl.handle.net/10150/625447 az1697 August 2017 Solar Photovoltaic (PV) Site Assessment Dr. Ed Franklin Introduction An important consideration when installing a solar photovoltaic (PV) array for residential, commercial, or agricultural operations is determining the suitability of the site. A roof-top location for a residential application may have fewer options due to limited space (roof size), type of roofing material (such as a sloped shingle, or a flat roof), the orientation (south, east, or west), and roof-mounted structures such as vent pipe, chimney, heating & cooling units. A location with open space may utilize a ground-mount system or pole-mount system. Determining the physical location of a solar PV array is a critical step to optimize energy output performance of the system. The ideal location is where solar modules are exposed to full sunshine from sun up to sun down without worry about shade cast on the modules from trees, power poles, guide wires, vent pipes, or nearby buildings, or the changing location of the sun. In the Northern Hemisphere, solar PV arrays are oriented to the south toward the Equator. Over the course of a calendar year, the sun’s altitude (height) in the sky changes. For example, during the month of June, the sun reaches its highest point in the sky on June 21 at 12:00 noon (summer solstice), and the sun Figure 1. -
The Solar Resource
CHAPTER 7 THE SOLAR RESOURCE To design and analyze solar systems, we need to know how much sunlight is available. A fairly straightforward, though complicated-looking, set of equations can be used to predict where the sun is in the sky at any time of day for any location on earth, as well as the solar intensity (or insolation: incident solar Radiation) on a clear day. To determine average daily insolation under the com- bination of clear and cloudy conditions that exist at any site we need to start with long-term measurements of sunlight hitting a horizontal surface. Another set of equations can then be used to estimate the insolation on collector surfaces that are not flat on the ground. 7.1 THE SOLAR SPECTRUM The source of insolation is, of course, the sun—that gigantic, 1.4 million kilo- meter diameter, thermonuclear furnace fusing hydrogen atoms into helium. The resulting loss of mass is converted into about 3.8 × 1020 MW of electromagnetic energy that radiates outward from the surface into space. Every object emits radiant energy in an amount that is a function of its tem- perature. The usual way to describe how much radiation an object emits is to compare it to a theoretical abstraction called a blackbody. A blackbody is defined to be a perfect emitter as well as a perfect absorber. As a perfect emitter, it radiates more energy per unit of surface area than any real object at the same temperature. As a perfect absorber, it absorbs all radiation that impinges upon it; that is, none Renewable and Efficient Electric Power Systems. -
3. Calculating Solar Angles
3. Calculating Solar Angles These equations should be used keeping all of the angles in radians even though with some of the equations it does not matter whether degrees or radians are used. 3.1. Declination Angle The declination angle is described in figure 1.5 and 1.6. The equation used to calculate the declination angle in radians on any given day is: 284 + n / = 23.45 sin2 (3.1) 180 365.25 where: / GHFOLQDWLRQDQJOH UDGV n = the day number, such that n = 1 on the 1st January. Figure 3.1: The variation in the declination angle throughout the year. The declination angle is the same for the whole globe on any given day. Figure 3.1 shows the change in the declination angle throughout a year. Because the period of the Earth's complete revolution around the Sun does not coincide exactly with the calendar year the declination varies slightly on the same day from year to year. 3.2. The Hour Angle The hour angle is described in figure 1.6 and it is positive during the morning, reduces to zero at solar noon and becomes increasingly negative as the afternoon progresses. Two equations can be used to calculate the hour angle when various angles are knoZQ QRWHWKDW/FKDQJHVIURPGD\WR GD\DQG.DQG$FKDQJHZLWKWLPHWKURXJKRXWWKHGD\ . cos sin A Z sin & = − (3.2) cos/ sin . − sin /sin & sin & = (3.3) cos/cos& where: & WKHKRXUDQJOH . WKHDOWLWXGHDQJOH AZ= the solar azimuth angle; / WKHGHFOLQDWLRQDQJOH & = observer's latitude. Note that at solar noon the hour angle equals zero and since the hour angle changes at 15° per hour it is a simple matter to calculate the hour angle at any time of day. -
Solar Wind Fluence to the Lunar Surface
44th Lunar and Planetary Science Conference (2013) 2015.pdf SOLAR WIND FLUENCE TO THE LUNAR SURFACE. D. M. Hurley1,3, W. M. Farrell2,3, 1JHU Applied Phys- ics Laboratory ([email protected]), 2NASA Goddard Space Flight Center, 3NASA Lunar Science Institute. Monolayers delivered in one lunation Introduction: The unperturbed solar wind bom- 90 bards the dayside of the Moon with electrons, protons, 60 and heavier ions throughout most of a lunation. Ex- cept when the Moon is in the Earth’s magnetotail for a 30 few days each lunation, the solar wind (shocked solar 0 N. Latitude wind in the magnetosheath, and unshocked solar wind -30 beyond Earth’s bow shock) has access to the dayside -60 surface of the Moon. Investigations of how the solar -90 wind could contribute to the composition and optical 0 90 180 270 360 properties of the lunar surface have a long history (e.g. E. Longitude [1-7]. Yet, it is instructive to revisit this issue and ex- Figure 2. The solar wind proton fluence as a function of amine the solar wind interaction piece by piece. selenographic position is shown in terms of fractions of Delivered Flux: The upper limit on the solar wind an equivalent monolayer of OH. The solid lines neglect thermal effects while the dashed lines include thermal as a potential source of OH can be established by as- effects. suming all of the incident solar wind protons are re- tained in the lunar regolith. The quiescent solar wind is implanted 3He as a resource guide. Fig. 2 shows the variable, but has density, n, of ~5 p+cm-3 and velocity, calculated fluence for one lunation assuming a spheri- v, of ~350 km s-1. -
The Observational Analemma
On times and shadows: the observational analemma Alejandro Gangui IAFE/Conicet and Universidad de Buenos Aires, Argentina Cecilia Lastra Instituto de Investigaciones CEFIEC, Universidad de Buenos Aires, Argentina Fernando Karaseur Instituto de Investigaciones CEFIEC, Universidad de Buenos Aires, Argentina The observation that the shadows of objects change during the course of the day and also for a fixed time during a year led curious minds to realize that the Sun could be used as a timekeeper. However, the daily motion of the Sun has some subtleties, for example, with regards to the precise time at which it crosses the meridian near noon. When the Sun is on the meridian, a clock is used to ascertain this time and a vertical stick determines the angle the Sun is above the horizon. These two measurements lead to the construction of a diagram (called an analemma) as an extremely useful resource for the teaching of astronomy. In this paper we report on the construction of this diagram from roughly weekly observations during more than a year. PACS: 01.40.-d, 01.40.ek, 95.10.-a Introduction Since early times, astronomers and makers of sundials have had the concept of a "mean Sun". They imagined a fictitious Sun that would always cross the celestial meridian (which is the arc joining both celestial poles through the observer's zenith) at intervals of exactly 24 hours. This may seem odd to many of us today, as we are all acquainted with the fact that one day -namely, the time it takes the Sun to cross the meridian twice- is in fact 24 hours and there is no need to invent any new Sun. -
HOW to BE CREATIVE with DIRECTIONAL LIGHTING and PORTRAITURE Quick Guide Written by Ludmila Borošová
Photzy HOW TO BE CREATIVE WITH DIRECTIONAL LIGHTING AND PORTRAITURE Quick Guide Written by Ludmila Borošová HOW TO BE CREATIVE WITH DIRECTIONAL LIGHTING AND PORTRAITURE // © PHOTZY.COM 1 One of the common things we often hear professional Today, we’ll cover the following: photographers say is, “If you are a professional, you avoid shooting at noon.” It is partially true, because experienced • Reasons why photographers avoid shooting in photographers usually customize their schedule in order directional lighting to increase their chances of getting a type of light they • Tips before, during, and after a photoshoot for prefer. That is, usually a soft, beautiful light achieved achieving better outcomes in directional lighting by the golden hour near sunrise or sunset hours. I can’t Recommended Reading: If you’re interested in blame them – I’m one of them, preferring to work in learning more about light and how you can use it to my comfortable space of soft light, no harsh shadows, improve your photography, grab a copy of Photzy’s and beautiful “bokeh.” But what really does bring you bestselling premium guide: Understanding Light Book a step closer to becoming a professional? Being able to Two. shoot amazing pictures regardless of lighting conditions? Adapting to new and uncomfortable situations? The answer is yes, but first of all, you have to seek them. HOW TO BE CREATIVE WITH DIRECTIONAL LIGHTING AND PORTRAITURE // © PHOTZY.COM 2 WHY DO PHOTOGRAPHERS PREFER GOLDEN HOUR LIGHT AND AVOID SHOOTING AT NOON? There are various reasons why this has been the trend over the past years, and it is still a preferred time of day for the majority. -
Solar Hour Angle ECE 333 © 2002 – 2018 George Gross, University of Illinois at Urbana-Champaign, All Rights Reserved
ECE 333 – GREEN ELECTRIC ENERGY 12. The Solar Energy Resource George Gross Department of Electrical and Computer Engineering University of Illinois at Urbana–Champaign ECE 333 © 2002 – 2018 George Gross, University of Illinois at Urbana-Champaign, All Rights Reserved. 1 SOLAR ENERGY Solar energy is the most abundant renewable energy source and is considered to be very clean Solar energy is harnessed for many applications, including electricity generation, lighting and steam and hot water production ECE 333 © 2002 – 2018 George Gross, University of Illinois at Urbana-Champaign, All Rights Reserved. 2 Page 1 SOLAR RESOURCE LECTURE The solar energy source Extraterrestrial solar irradiation Analysis of solar position in the sky and its application to the determination of optimal tilt angle design for a solar panel sun path diagram for shading analysis solar time and civil time relationship ECE 333 © 2002 – 2018 George Gross, University of Illinois at Urbana-Champaign, All Rights Reserved. 3 UNDERLYING BASIS: THE SUN IS A LIMITLESS ENERGY SOURCE .files.wordpress.com/2012/11 johnosullivan Source : http://Source ECE 333 © 2002 – 2018 George Gross, University of Illinois at Urbana-Champaign, All Rights Reserved. 4 Page 2 SOLAR ENERGY The thermonuclear reactions, as the hydrogen atoms fuse together to form helium in the sun, are the source of solar energy In every second, roughly 4 billion kg of mass are converted into energy, as described by Einstein’s famous mass–energy equation This immense energy generated is huge so as to keep the sun at very high temperatures at all times ECE 333 © 2002 – 2018 George Gross, University of Illinois at Urbana-Champaign, All Rights Reserved. -
Calculate and Analysis of Air Mass and Solar Angles of Mosul City
------ Raf. J. Sci., Vol. 27, No.4, pp.57-65, 2018------ Calculate and Analysis of Air Mass and Solar Angles of Mosul City Taha M. Al-Maula Abdullah I. Al-Abdulla Department of Physics/ College of Science/ University of Mosul E-mail: [email protected] E-mail: [email protected]. (Received 16 / 4/ 2018 ; Accepted 12 / 6 / 2018 ) ABSTRACT The solar radiation energy of the city of Mosul was calculated according to the value of AM = 1.24 on 21 March and September, theoretically using formula 7 and measuring it practically using the radiometer of the intensity of the optical radiation emitted from the solar simulator that was designed in the laboratory. There are values of 982 W / m2 and 996 W / m2 , respectively, comparing these values in Table 1 with published values for other sites. Table (1) AM values and solar radiation intensity theoretically using formula (7) and practically for different angular values. For the purpose of solar simulators manufacturing, the air mass (AM) were calculated for the city of Mosul at Altitude line (36.35o) and Longitude line (43.100) and at a height of 220 meters above sea level, this required the computation of the Solar inclination angle (δ), the hour angle ( , the Solar elevation angle (h) and the zenith angle (Z), in addition to that, the calculations were studied in specified day, chosen at the 21st of each month From sunrise to sunset, which is the daylight hours. The study showed that, the values of AM become equals to one at twelve o'clock and 1.24 on the 21st of March and September when the sun at the zenith angle 36.35o.