... Earth at Night . ... The date was July 4th and the fiery streaks were part of the traditional annual celebration of independence day in the United States. ... Rays from an Unexpected Aurora . ... Spiral Galaxy NGC 2997 from VLT . ... The Galactic Center A Radio Mystery . ... Comet 57P Falls to Pieces . ... Orbiting the Sun every 5.9 years or so this faint comet - also christened Comet 57P/du Toit-Neujmin-Delporte for its three 1941 co-discoverers - is simply.. Sunspots and Solar Active Regions . ...

... ESO is building what will be the World's largest optical telescope array, The Very Large Telescope (VLT). The VLT Project organisation is responsible for the design and construction of the Unit Telescopes, including enclosures, optics, adapter-rotators and coating unit. ... Unit Telescopes Overview - This page is outdated, an update is in process. ... Secondary mirror (M2 Unit) - This page is outdated, an update is in process. ... Coating Unit - This page is outdated, an update is in process. ...

Wave-Particle Duality of Light. click here to see a wave experiment . ... In the wave theory, greater light intensity simply means more photons. Each photon ejects electrons in the same way, so more intensity means more electrons. Threshold frequency and electron K.E. should not be affected by intensity. ... Light frequencies below the threshold eject no electrons, no matter how intense the light. Light frequencies above the threshold eject electrons, no matter how low the intensity. ...

... Before the modern era of technological astronomy, to know anything about the Universe beyond our planet we relied on light. ... Historically the two rival ideas were that light was either a stream of tiny bullet-like particles or a wave wobbling its way through space. ... The light we see (visible light which is not the tautology it sounds) is only part of the electromagnetic spectrum, a great sweep of radiations which also includes radio, infra-red, ultra-violet, x-rays and gamma rays. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Armagh Observatory, 30 July 2015: The sky above a nearby "failed star" or brown dwarf lying in the summer constellation Lyra shimmers with a beautiful green and yellow aurora ten thousand times brighter than the northern lights. ... Even a few years ago, brown dwarfs were thought by most astronomers to be incapable of emitting any significant radio emission, so its first detection came as a great surprise. ...

... The eleven years cycle of Sun's activity is approaching its maximum! From August 24th to 29th a team of astronomers, engineers and astro-photographers will travel to southern Greenland to observe the Northern Lights (Aurora Borealis), a phenomenon expected to be particularly spectacular during this period. ... Auroras . The wonderful celestial spectacle of the aurora occurs when very energetic particles from the Sun reach the Earth's atmosphere via the solar wind. ... About GLORIA . ...

DGL Plots . Single Scattering Albedo . ... Scattering Phase Function Asymmetry . ... DGL Studies . ... Witt 1968 . ... Yes . No g determination possible . Witt & Lillie 1973 . ... Superseded by Lillie Witt 1976 . Lillie & Witt 1976 . ... Superseded by Witt et al. ... Witt et al. ... numerical int.; TD-1 star catalog; clumped dust . ... Witt, A. N. 1968, ApJ, 152, 59 . ... Interstellar dust scattering properties from: [ Diffuse Galactic Light ] [ Reflection Nebulae ] [ Dark Clouds ] . ...

... Home Lectures Lecture Series 2011-2012 Lecture Series 2011-2012 ? тАЬA Ray of Light in a Sea of Dark (Matter)тАЭ ? Charles Keeton . ... Charles Keeton , associate professor of physics and astronomy at Rutgers University and faculty director of the Aresty Research Center for Undergraduates , will speak to the AAA Friday, March 2, on тАЬA Ray of Light in a Sea of Dark (Matter).тАЭ The free public lecture begins at 6:15 p.m. in the Kaufmann Theater of the€а American Museum of Natural History . ...

... Главная . ... Новости . ... Проекты . Любителям астрономии . Проект ISON . ... Подробнее . ... Категория: Новости проекта ISON . ... Метки: Космический мусор ,љ Астероиды ,љ Гамма-всплески ,љ Любителям астрономии ,љ Кометы љ . ... Метки: Космический мусор ,љ Астероиды ,љ Любителям астрономии љ . ... Новости обсерваторий проекта] - Обсерватория Кубанского государственного университета от Иванов А - 09.04.2016 11:08:49 . ... 1999-2013 Copyright "Астрономия и Телескопостроение" . ...

... 2009 October 29 . Zodiacal Light Over Laguna Verde . ... Once considered a false dawn , this triangle of light is actually Zodiacal Light , light reflected from interplanetary dust particles . ... The band of our Milky Way Galaxy on the left mirrors the zodiacal band. ... Zodiacal light is so bright in the north this time of year because the dust band is oriented nearly vertical at sunrise, so that the thick air near the horizon does not block out relatively bright reflecting dust . ...

... Bad Astronomy . Misconceptions . ... Bad Astronomy : "We're light years more advanced than our competition!" ... Even the closest astronomical object, the Moon, is 400,000 kilometers away! ... A beam of light will travel 9,500,000,000,000 kilometers in one year. This distance is defined as a light year ; the distance light travels in a year. ... This is another example of Bad Astronomy; like a light year, a parsec is a unit of distance, not time (to be specific, it equals 3.26 light years) . ...

Perhaps the greatest theoretical achievement of physics in the 19th century was the discovery of electromagnetic waves. ... It is possible to use this to define a unit of electric charge, as the charge which repels a similar charge at a distance of, say, 1 meter, with a force of unit strength (actual formulas make this precise). ... But "field" originally only meant the force a magnet or an electric charge could expect at a point in space, if it were placed there. ...

... STScI-PRC00-36 GHOSTLY REFLECTIONS IN THE PLEIADES NASA's Hubble Space Telescope has caught the eerie, wispy tendrils of a dark interstellar cloud being destroyed by the passage of one of the brightest stars in the Pleiades star cluster. ... In 1890, American astronomer E. E. Barnard, observing visually with the Lick Observatory 36-inch telescope in California, discovered an exceptionally bright nebulosity adjacent to the bright Pleiades star Merope. ...

An Ancient Universe: How Astronomers Know the Vast Scale of Cosmic Time . THE ANCIENT UNIVERSE . c) The Age of Light from the Most Distant Galaxies: The "Time Machine" Effect . ... Thus we are actually seeing these galaxies not as they are today, but as they were billions of years ago. ... The Universe: An Overview | ... The Ancient Universe - The Age of the Expanding Universe - The Age of the Oldest Stars - The Age of Light From Distant Galaxies - The Age of the Chemical Elements | ...

... Astrophysics Group . ... Aperture Synthesis with Light . ... MRAO Telescopes . ... Stars ? ... The astronomer?s desire to see things in ever greater detail is thwarted at optical wavelengths by the Earth?s atmosphere: making optical telescopes larger does not provide more detail in the images. ... The Cambridge Optical Aperture Synthesis Telescope (COAST) has been developed to meet the very demanding task of imaging the surfaces of individual stars and studying the interaction of close pairs of...

Photon/Particle Counting Image Measurement System : PIAS-TI . The PIAS-TI is an extremely sensitive image measurement device developed for imaging and quantification in ultimate levels with an extremely small number of photons, electrons and charged particles. ... The PIAS-TI is a measuring system that makes use of the technology of the photon counter to detect the input positions of individual photons or particles, and accumulate them to create an image. ...

Next: A Universal Diagram for Up: ``Ecology'' of Magnetic Rotators Previous: The Corotation Radius . The interaction of a magnetic rotator with the surrounding plasma to a large extent depends on the relation between the four characteristic radii: the stopping radius, , the gravitational capture radius,   , the light cylinder radius,   , and the corotation radius,   . ... Hence, the classification of the interaction regimes may well mean the classification of magnetic rotators. ...

The efficiency of interaction of radiation with a particle and hence its optical properties depend on the particle chemical composition, size, shape, structure, etc. ... Particle size expressed in units of the wavelength of incident radiation, together with chemical composition, most strongly affects the optical properties of a scatterer. ... There are many methods to solve the light-scattering problem for a homogeneous spheroid (our survey of the light-scattering methods see here ). ...

... X-rays are made up of photons that are emitted from stars, or quasars, or supernovae, the sun, or simply: anything that is undergoing a change either in size or temperature or giving out heat. ... in an X-ray binary star system, in which one normal star's orbit is crossed by a neutron star, when the neutron star by means of gravitational pull takes matter from the normal star X-rays form. ... Artists conception of a normal star (HDE 226868) and a black hole taking matter from the normal star. ...

... Energy . ... The free ions and electrons in a plasma behave the same way. Knowing the temperature of the high atmosphere of Earth, or that of the Sun, we can calculate energies expected of ions and electrons found there. However, ions and electrons actually observed in space are often much, much more energetic, and may move at a respectable fraction of the velocity of light (300,000 km/sec or 186,000 miles/sec). ... Typical energy of an electron in the polar aurora. 40,000 ev . ... 50,000 ev . ...