Naked-Eye 100
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
View and Print This Publication
@ SOUTHWEST FOREST SERVICE Forest and R U. S.DEPARTMENT OF AGRICULTURE P.0. BOX 245, BERKELEY, CALIFORNIA 94701 Experime Computation of times of sunrise, sunset, and twilight in or near mountainous terrain Bill 6. Ryan Times of sunrise and sunset at specific mountain- ous locations often are important influences on for- estry operations. The change of heating of slopes and terrain at sunrise and sunset affects temperature, air density, and wind. The times of the changes in heat- ing are related to the times of reversal of slope and valley flows, surfacing of strong winds aloft, and the USDA Forest Service penetration inland of the sea breeze. The times when Research NO& PSW- 322 these meteorological reactions occur must be known 1977 if we are to predict fire behavior, smolce dispersion and trajectory, fallout patterns of airborne seeding and spraying, and prescribed burn results. ICnowledge of times of different levels of illumination, such as the beginning and ending of twilight, is necessary for scheduling operations or recreational endeavors that require natural light. The times of sunrise, sunset, and twilight at any particular location depend on such factors as latitude, longitude, time of year, elevation, and heights of the surrounding terrain. Use of the tables (such as The 1 Air Almanac1) to determine times is inconvenient Ryan, Bill C. because each table is applicable to only one location. 1977. Computation of times of sunrise, sunset, and hvilight in or near mountainous tersain. USDA Different tables are needed for each location and Forest Serv. Res. Note PSW-322, 4 p. Pacific corrections must then be made to the tables to ac- Southwest Forest and Range Exp. -
RADIAL VELOCITIES in the ZODIACAL DUST CLOUD
A SURVEY OF RADIAL VELOCITIES in the ZODIACAL DUST CLOUD Brian Harold May Astrophysics Group Department of Physics Imperial College London Thesis submitted for the Degree of Doctor of Philosophy to Imperial College of Science, Technology and Medicine London · 2007 · 2 Abstract This thesis documents the building of a pressure-scanned Fabry-Perot Spectrometer, equipped with a photomultiplier and pulse-counting electronics, and its deployment at the Observatorio del Teide at Izaña in Tenerife, at an altitude of 7,700 feet (2567 m), for the purpose of recording high-resolution spectra of the Zodiacal Light. The aim was to achieve the first systematic mapping of the MgI absorption line in the Night Sky, as a function of position in heliocentric coordinates, covering especially the plane of the ecliptic, for a wide variety of elongations from the Sun. More than 250 scans of both morning and evening Zodiacal Light were obtained, in two observing periods – September-October 1971, and April 1972. The scans, as expected, showed profiles modified by components variously Doppler-shifted with respect to the unshifted shape seen in daylight. Unexpectedly, MgI emission was also discovered. These observations covered for the first time a span of elongations from 25º East, through 180º (the Gegenschein), to 27º West, and recorded average shifts of up to six tenths of an angstrom, corresponding to a maximum radial velocity relative to the Earth of about 40 km/s. The set of spectra obtained is in this thesis compared with predictions made from a number of different models of a dust cloud, assuming various distributions of dust density as a function of position and particle size, and differing assumptions about their speed and direction. -
Atmospheric Effects Are Looking Up
Atmospheric Effects are Looking Up OASI Workshop 21st May 2018 by Olaf Kirchner Ever seen one of these ? OK, so how about one of these? Atmospheric Effects - caused by sun- or moonlight interacting with liquid water or ice in the air - surprisingly common - always beautiful and one or several phenomena may be seen at the same time - can be in-your-face obvious or very subtle, and ... - ... span the entire sky - a challenge to photograph - very complicated theoretical explanations Effects caused by Liquid Water Droplets - rainbows - glories, Heiligenschein and the Spectre of the Brocken - aureoles / coronae - nacreous / iridescent / Mother-of-Pearl clouds Rainbow Rainbow Ray paths for primary rainbow Ray paths through a spherical water drop Ray paths for secondary rainbow Secondary Rainbow Secondary rainbow Alexander’s Band Supernumerary rainbow Primary rainbow Rainbow Gap in cloud behind observer = partial rainbow Rainbow in spray, Geneva Jet d’Eau Supernumerary Rainbow Interference colours from different lengths of light path Rainbow Circular rainbow seen from an aircraft Rainbows don’t reflect ... Glory Colourful diffraction rings centred on the antisolar point, caused by reflection from spherical droplets Glory ... i.e. centred on where the shadow of your head would be! Brockengespenst = Spectre of the Brocken Taken against fog from Golden Gate Bridge Brocken (1142 m) . Highest point in the Harz mountains Heiligenschein = Halo Antisolar point in hydrothermal steam ... scary stuff Heiligenschein ... i.e. a glory centred on your head -
Atmospheric Phenomena by Feist
Atmospheric optical phenomena An introductory guide by Mike Feist Effects caused by water droplets— rainbows and coronae The most well known optical sky effect is the rainbow. This, as most people know, sometimes occurs when the Sun is out and it is raining. To see a rainbow you must stand with your back to the Sun with the raindrops in front of you. It does not have to be raining where you are standing but in the direction that you are looking. The arc of the primary (main) bow is centred on the antisolar point, the spot directly oppo- site the Sun, and has a radius of 42°. The antisolar point is actually centred on the shadow of your head. If the Sun is rising or setting and therefore on the horizon, the primary rainbow will be a complete semi- circle and the top will be 42° up in the sky. If, on the other hand, the Sun is 42° up in the sky, the primary bow will be on the horizon, the top just rising or setting. Con- ventionally the rainbow is said to have John Constable. Hampstead Heath with a Rainbow (1836). seven colours but all we need to remember seen in the spray near waterfalls and artifi- ous forms but with a six-sided shape. They is that, in the primary bow, the red is on cial rainbows can be made using a garden may be as flat hexagonal plates or long the outside and the blue on the inside. Out- hose. Rainbows are one of the easiest opti- hexagonal prisms or as a combination of side the primary bow sometimes there is cal effects to photograph although they the two. -
Midnight Sun and Northern Lights Name
volume 3 Midnight Sun and issue 5 Northern Lights It’s black, which absorbs the sun’s warmth. In fact, polar midnight, bears feel hot if the temperature rises above freezing. but the sun The polar nights are long and dark, but sometimes is shining there’s a light show in the sky. The northern lights, which brightly. Where are called the aurora, are often green or pink. They seem are you? You’re to wave and dance in the sky. Auroras are caused by gas in the Arctic, particles that were thrown off by the sun. These particles near the North collide in Earth’s atmosphere and make a beautiful show. Pole. During Few people live in the Arctic because it’s so cold, but the arctic Canada, Greenland, Norway, Iceland, and Russia are summer, the good places to see the midnight sun and the aurora. In ©2010 by Asbjørn Floden in Flickr. Some rights reserved http://creativecommons.org/licenses/by-nc/2.0/deed.en sun doesn’t fact, Norway is often called the Land of the Midnight set for months. Instead, it goes around the horizon. You Sun. could read outside at midnight. As you travel south The temperature stays warm, too, although not as from the North Pole, warm as where you live. The average temperature in there is less midnight sun the summer near the North Pole is about 32 degrees, and fewer northern lights. or freezing. That may sound cold to you, but it’s warm It gets warmer, too. Soon, in the Arctic. -
Disrupted Solar Transit at 140 Mhz Over the Mexican Array Radio Telescope Due Space Weather Events
URSI AP-RASC 2019, New Delhi, India; 09 - 15 March 2019 Disrupted Solar Transit at 140 MHz over the Mexican Array Radio Telescope due Space Weather Events *Victor De la Luz(1)(2), Julio Mejia-Ambriz(1)(2), and Americo Gonzalez(2) (1) Conacyt, Servicio de Clima Espacial Mexico, Morelia, Mexico. 58190. http://www.sciesmex.unam.mx (2) Instituto de Geofisica, Unidad Michoacan, UNAM, Morelia, Mexico. 58190. Abstract Figure 2 show two solar transits centered at peak, for 22 (green line, quiet) and 26 (blue line, close to the solar flare) In this work we present the records of the disrupted so- June, 2015. We observed clearly the changes of amplitude lar transits at 140 MHz at Mexican Array Radio Telescope of the signal. (MEXART) related with active regionsand a solar flare dur- ing the week of June 20 - 26, 2015. 4 Conclusions 1 Introduction We show that space weather, in particular solar flares, mod- ifies the antenna pattern related with solar transit in the MEXART at 140 MHz. The increase in the flux saturated The transit instrument Mexican Array Radio Telescope the instrument at June 22. For this reasson, we used the 5Th (MEXART) is located in Coeneo, Mexico. Their main pro- lateral left lobe to characterize the increase of the flux. We pose is record extra-galactic radio source to observe the observed that at peak, the flux increases 16 mV in the max- interplanetary scintillation (IPS) [3]. The radio telescope imum level at June 22, 2015 compared against the baseline have central frequency of 139.65 MHz and bandwidth of 2 of the transit in quiet conditions. -
1 Comparison of Solar Evaluation Tools
COMPARISON OF SOLAR EVALUATION TOOLS: FROM LEARNING TO PRACTICE Sophia Duluk Heather Nelson Department of Architecture Department of Architecture University of Oregon University of Oregon Eugene, OR 97403 Eugene, OR 97403 Email: [email protected] Email: [email protected] Alison Kwok Department of Architecture University of Oregon Eugene, OR 97403 Email: [email protected] ABSTRACT obstacles to the use of software and a number of misunderstandings about principles and concepts of solar Solar tools and software have evolved in the last ten years to radiation. These can cause under- or overestimations, assist designers in evaluating a site for shading, solar access, leading to heavy energy consequences when handling daylighting design, photovoltaic placement, and passive building loads and thermal comfort. solar heating potential. This paper presents a comparative evaluation of solar site analysis tools as base cases for This study focuses on comparing six tools readily available evaluation. We present the results from on site to design professionals: Solar Transit (1), Solar Pathfinder measurements, software predictions, output accuracy, ease (http://www.solarpathfinder.com/index), Solmetric Suneye of use, design inputs needed for Passive House Planning (http://www.solmetric.com), HORIcatcher+Meteonorm Protocol (PHPP), and other criteria to discuss the (http://www.meteotest.ch/en/footernavi/solar_energy/horicat capabilities of the tools in education and in architectural cher/) and two iPhone applications. Additionally, the study design practice. We compare six tools: Solar Transit, Solar will examine shading protocols used for the Passive House Pathfinder + Solar Pathfinder Assistant software, Solmetric Planning Package (PHPP) to see how the tools compare to Suneye + Thermal Assistant Software, HORIcatcher + the PHPP shading assumptions, and determine the Meteonorm, and two iPhone applications. -
ESSENTIALS of METEOROLOGY (7Th Ed.) GLOSSARY
ESSENTIALS OF METEOROLOGY (7th ed.) GLOSSARY Chapter 1 Aerosols Tiny suspended solid particles (dust, smoke, etc.) or liquid droplets that enter the atmosphere from either natural or human (anthropogenic) sources, such as the burning of fossil fuels. Sulfur-containing fossil fuels, such as coal, produce sulfate aerosols. Air density The ratio of the mass of a substance to the volume occupied by it. Air density is usually expressed as g/cm3 or kg/m3. Also See Density. Air pressure The pressure exerted by the mass of air above a given point, usually expressed in millibars (mb), inches of (atmospheric mercury (Hg) or in hectopascals (hPa). pressure) Atmosphere The envelope of gases that surround a planet and are held to it by the planet's gravitational attraction. The earth's atmosphere is mainly nitrogen and oxygen. Carbon dioxide (CO2) A colorless, odorless gas whose concentration is about 0.039 percent (390 ppm) in a volume of air near sea level. It is a selective absorber of infrared radiation and, consequently, it is important in the earth's atmospheric greenhouse effect. Solid CO2 is called dry ice. Climate The accumulation of daily and seasonal weather events over a long period of time. Front The transition zone between two distinct air masses. Hurricane A tropical cyclone having winds in excess of 64 knots (74 mi/hr). Ionosphere An electrified region of the upper atmosphere where fairly large concentrations of ions and free electrons exist. Lapse rate The rate at which an atmospheric variable (usually temperature) decreases with height. (See Environmental lapse rate.) Mesosphere The atmospheric layer between the stratosphere and the thermosphere. -
Atmospheric Optics
53 Atmospheric Optics Craig F. Bohren Pennsylvania State University, Department of Meteorology, University Park, Pennsylvania, USA Phone: (814) 466-6264; Fax: (814) 865-3663; e-mail: [email protected] Abstract Colors of the sky and colored displays in the sky are mostly a consequence of selective scattering by molecules or particles, absorption usually being irrelevant. Molecular scattering selective by wavelength – incident sunlight of some wavelengths being scattered more than others – but the same in any direction at all wavelengths gives rise to the blue of the sky and the red of sunsets and sunrises. Scattering by particles selective by direction – different in different directions at a given wavelength – gives rise to rainbows, coronas, iridescent clouds, the glory, sun dogs, halos, and other ice-crystal displays. The size distribution of these particles and their shapes determine what is observed, water droplets and ice crystals, for example, resulting in distinct displays. To understand the variation and color and brightness of the sky as well as the brightness of clouds requires coming to grips with multiple scattering: scatterers in an ensemble are illuminated by incident sunlight and by the scattered light from each other. The optical properties of an ensemble are not necessarily those of its individual members. Mirages are a consequence of the spatial variation of coherent scattering (refraction) by air molecules, whereas the green flash owes its existence to both coherent scattering by molecules and incoherent scattering -
Planit! User Guide
ALL-IN-ONE PLANNING APP FOR LANDSCAPE PHOTOGRAPHERS QUICK USER GUIDES The Sun and the Moon Rise and Set The Rise and Set page shows the 1 time of the sunrise, sunset, moonrise, and moonset on a day as A sunrise always happens before a The azimuth of the Sun or the well as their azimuth. Moon is shown as thick color sunset on the same day. However, on lines on the map . some days, the moonset could take place before the moonrise within the Confused about which line same day. On those days, we might 3 means what? Just look at the show either the next day’s moonset or colors of the icons and lines. the previous day’s moonrise Within the app, everything depending on the current time. In any related to the Sun is in orange. case, the left one is always moonrise Everything related to the Moon and the right one is always moonset. is in blue. Sunrise: a lighter orange Sunset: a darker orange Moonrise: a lighter blue 2 Moonset: a darker blue 4 You may see a little superscript “+1” or “1-” to some of the moonrise or moonset times. The “+1” or “1-” sign means the event happens on the next day or the previous day, respectively. Perpetual Day and Perpetual Night This is a very short day ( If further north, there is no Sometimes there is no sunrise only 2 hours) in Iceland. sunrise or sunset. or sunset for a given day. It is called the perpetual day when the Sun never sets, or perpetual night when the Sun never rises. -
Xtrackers (Ie) Plc
XTRACKERS (IE) PLC (An umbrella fund with variable share capital and segregated liability between funds) Condensed Interim Unaudited Report for the financial period ended 30 June 2020 XTRACKERS (IE) PLC CONTENTS Page General Information 1 Investment Manager's Report 14 Portfolio of Investments Xtrackers EUR Credit 12.5 Swap UCITS ETF 23 Xtrackers Portfolio Income UCITS ETF 25 Xtrackers MSCI Nordic UCITS ETF 26 Xtrackers Germany Mittelstand & MidCap UCITS ETF 30 Xtrackers MSCI North America High Dividend Yield UCITS ETF 34 Xtrackers MSCI AC World UCITS ETF 40 Xtrackers MSCI USA UCITS ETF 74 Xtrackers S&P 500 Equal Weight UCITS ETF 89 Xtrackers MSCI World UCITS ETF 101 Xtrackers FTSE Developed Europe ex UK Real Estate UCITS ETF 135 Xtrackers MSCI World Minimum Volatility UCITS ETF 137 Xtrackers MSCI World Momentum UCITS ETF 145 Xtrackers MSCI World Quality UCITS ETF 154 Xtrackers MSCI World Value UCITS ETF 162 Xtrackers MSCI GCC Select Swap UCITS ETF 172 Xtrackers FTSE All-World ex UK UCITS ETF 175 Xtrackers S&P 500 UCITS ETF 207 Xtrackers Russell 2000 UCITS ETF 220 Xtrackers Russell Midcap UCITS ETF 257 Xtrackers JPX-Nikkei 400 UCITS ETF 274 Xtrackers USD Corporate Bond UCITS ETF 285 Xtrackers MSCI World Financials UCITS ETF 321 Xtrackers MSCI World Health Care UCITS ETF 326 Xtrackers MSCI World Consumer Staples UCITS ETF 330 Xtrackers MSCI World Energy UCITS ETF 333 Xtrackers MSCI World Information Technology UCITS ETF 335 Xtrackers MSCI World Consumer Discretionary UCITS ETF 339 Xtrackers MSCI World Industrials UCITS ETF 344 Xtrackers -
Consecutive Midnight Shifts
Fatigue and Shiftwork: Consecutive Midnight Shifts Why is it so hard to work midnight shifts (“Mids”)? In a 24/7 operation, mids are unavoidable. It is what it is. The challenge is that you have to be alert when your circadian clock (internal body clock) is programmed to sleep. To prepare for a mid, you need to sleep in the daytime when your body clock is on alarm (resisting sleep). Working mids disrupts your sleep pattern which may lead to an increase in sleep debt (accumulation of getting less sleep than you need). Performance and alertness levels decrease with each passing day of shortened sleep. But what about consecutive mids? Are consecutive mids more fatiguing than working a single mid? Yes, because the more mids in a row, the larger the sleep debt, and the tougher the recovery. With one mid, sleep debt is acute and recovery (making up sleep by sleeping more on days off) is possible. With consecutive mids, sleep debt becomes chronic and recovery may require multiple full nights of recuperative sleep. Does working consecutive mid shifts affect performance and alertness? Yes. If you work a schedule associated with reduced opportunities for night time recovery sleep, that loss increases the likelihood of decrements in both work performance and alertness. These decrements are exponential during early morning hours when your body clock is at its lowest (around 0300-0500) and you naturally have the urge to sleep. It is scientifically proven that: • Incident/accident risk increases significantly on the 3rd and 4th consecutive mid shift