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It is a stream of photons that Each traveling in a wave-like pattern at right angles

What is Electromagnetic radiation. Infrared cosmos All objects emit infrared radiation. Infrared detectors detect wavelengths which are between wavelengths of about 1 and 300 microns (a micron is one millionth of a meter)

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It is a stream of photons that Each traveling in a wave-like pattern at right angles

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  1. What is Electromagnetic radiation • Infrared cosmos • All objects emit infrared radiation. • Infrared detectors detect wavelengths which are between wavelengths of about 1 and 300 microns (a micron is one millionth of a meter) • The human eye detects only 1% of light at 0.69 microns, and 0.01% at 0.75 microns, and so effectively cannot see wavelengths longer than about 0.75 microns unless the light source is extremely bright. • It is a stream of photons that • Each traveling in a wave-like pattern at right angles • Moving at the speed of light • Carrying some amount of energy. They differ in the amount of energy of the photons. Absorption of Electromagnetic waves Gamma and X-ray: Oxygen and Nitrogen UV rays: Oxygen and Ozone Infrared waves: Water Ultraviolet Waves Wave-particle duality of light: Light behaves like a wave and particle Trend: Low energy photons behave more like waves while higher energy photons behave more like particles. This affects how detectors and telescopes are designed to try to 'see' EM radiation from very low to very high energies. Effects: Sunburns and skin cancer Detecting cool objects Sun at extreme UV wavelength How earth glows in UV light Exploring the early universe • Hottest and the most active objects in the cosmos give off large amounts of ultraviolet energy. • Applications: • Discern the … • Chemical composition • Densities • Temperatures of the interstellar medium • Temperature and composition of hot young stars. • Sterilise glassware • Signature of hotter objects E = h x nu Where E = Energy H= Planck’s constant = 6.626 x 10-27 erg-seconds Nu = Frequency 299,792,458 m/s X-rays and Gamma rays Sources of Radiowaves X rays and some gamma rays are produced throughout the universe by the same catastrophic astrophysical events, such as supernovas and black holes. Quasars: one of a class of blue celestial objects having the appearance of stars when viewed through a telescope and currently believed to be the most distant and most luminous objects in the universe 2) Radio galaxies. Measuring Cosmic Radiation The infrared part of the spectrum is where the emission and absorption lines of virtually all molecules as well as numerous atoms and ions (electrically charged atoms) lie. Infrared spectroscopy is the primary way to detect these elements in space.

  2. http://www.google.com.sg/imgres?imgurl=http://andyxl.files.wordpress.com/2007/06/agn-cartoon.jpg&imgrefurl=http://andyxl.wordpress.com/2007/06/08/quasars-donuts-and-the-unified-faith/&usg=__ziYqqxnLf0XHGkLRAMqStHSDsFQ=&h=273&w=375&sz=17&hl=en&start=0&zoom=1&tbnid=zNnFl80ttARxZM:&tbnh=155&tbnw=202&prev=/images%3Fq%3DQuasars%26um%3D1%26hl%3Den%26client%3Dfirefox-a%26sa%3DX%26rls%3Dorg.mozilla:en-US:official%26biw%3D1280%26bih%3D619%26tbs%3Disch:1&um=1&itbs=1&iact=rc&dur=330&ei=-8N_TN6nPJD8vQOPs52FBA&oei=-8N_TN6nPJD8vQOPs52FBA&esq=1&page=1&ndsp=18&ved=1t:429,r:2,s:0&tx=128&ty=66http://www.google.com.sg/imgres?imgurl=http://andyxl.files.wordpress.com/2007/06/agn-cartoon.jpg&imgrefurl=http://andyxl.wordpress.com/2007/06/08/quasars-donuts-and-the-unified-faith/&usg=__ziYqqxnLf0XHGkLRAMqStHSDsFQ=&h=273&w=375&sz=17&hl=en&start=0&zoom=1&tbnid=zNnFl80ttARxZM:&tbnh=155&tbnw=202&prev=/images%3Fq%3DQuasars%26um%3D1%26hl%3Den%26client%3Dfirefox-a%26sa%3DX%26rls%3Dorg.mozilla:en-US:official%26biw%3D1280%26bih%3D619%26tbs%3Disch:1&um=1&itbs=1&iact=rc&dur=330&ei=-8N_TN6nPJD8vQOPs52FBA&oei=-8N_TN6nPJD8vQOPs52FBA&esq=1&page=1&ndsp=18&ved=1t:429,r:2,s:0&tx=128&ty=66 http://www.google.com.sg/imgres?imgurl=http://www.oulu.fi/astronomy/astrophysics/pr/cenA.jpg&imgrefurl=http://www.oulu.fi/astronomy/astrophysics/pr/head.html&usg=__tq1EZyUjYiC6lJ83noZWHC05dhs=&h=593&w=599&sz=31&hl=en&start=0&zoom=1&tbnid=HsJZeb0Ix9Y8ZM:&tbnh=160&tbnw=167&prev=/images%3Fq%3DRadio%2Bgalaxies%26um%3D1%26hl%3Den%26client%3Dfirefox-a%26sa%3DN%26rls%3Dorg.mozilla:en-US:official%26biw%3D1280%26bih%3D619%26tbs%3Disch:1&um=1&itbs=1&iact=rc&dur=366&ei=2cR_TKTYHY-CvgO4x-iQBA&oei=2cR_TKTYHY-CvgO4x-iQBA&esq=1&page=1&ndsp=18&ved=1t:429,r:0,s:0&tx=118&ty=41 http://www.infoplease.com/ce6/sci/A0840734.html#axzz0yO2QxXMC http://science.hq.nasa.gov/kids/imagers/ems/uv.html http://2010smtpsec3.wikispaces.com/Ace+Suggestions http://www.windows2universe.org/physical_science/magnetism/em_ultraviolet.html http://www.answers.com/topic/gamma-ray-astronomy

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