- published: 15 Sep 2009
- views: 61347
Ultraviolet (UV) light is an electromagnetic radiation with a wavelength from 400 nm (750 THz) to 10 nm (30 PHz), shorter than that of visible light but longer than X-rays. Though usually invisible, under some conditions children and young adults can see ultraviolet down to wavelengths of about 310 nm, and people with aphakia (missing lens) can also see some UV wavelengths. Near-UV is visible to some insects and birds.
UV radiation is present in sunlight, and also produced by electric arcs and specialized lights such as mercury-vapor lamps, tanning lamps, and black lights. Although lacking the energy to ionize atoms, long-wavelength ultraviolet radiation can cause chemical reactions, and causes many substances to glow or fluoresce. Consequently, biological effects of UV are greater than simple heating effects, and many practical applications of UV radiation derive from its interactions with organic molecules.
Suntan, freckling and sunburn are familiar effects of over-exposure, along with higher risk of skin cancer. Living things on dry land would be severely damaged by ultraviolet radiation from the sun if most of it were not filtered out by the Earth's atmosphere, particularly the ozone layer. More-energetic, shorter-wavelength "extreme" UV below 121 nm ionizes air so strongly that it is absorbed before it reaches the ground. Ultraviolet is also responsible for the formation of bone-strengthening vitamin D in most land vertebrates, including humans. The UV spectrum thus has effects both beneficial and harmful to human health.
Excerpt from the TV documentary series "The Universe".
There are three types of UV radiation produced by the sun – UVA, UVB and UVC. UVA - causes skin cancer and ageing UVB - causes skin cancer and burning UVC - doesn't reach the ground. It is filtered out by the Earth's atmosphere. UV radiation cannot be seen by the eye or felt on the skin. When we feel the heat of the sun we are feeling the infrared rays, not the UV radiation.
We showed people what they looked like in ultraviolet, & wondered aloud if they wanted to put on some damn sunscreen already. https://twitter.com/thomasleveritt Music: 'Summer in the City - Starcadian remix' by Freedom Fry http://freedomfry.bandcamp.com/track/summer-in-the-city-starcadian-remix They are awesome. So is Starcadian. [Media: using YouTube's embed function anywhere on the web is completely okay, you don't need permission! But to copy it and repost on other platforms, like tv, you do need permission. This was a completely non-commercial project. Thanks.]
The experiment will show how we can detect the ultraviolet (or UV) radiation of the Sun which, although invisible, affects the skin, eyes and the DNA of our cells. "Detecting uv radiation" is a demonstration performed by staff of the Interactive Science and Technology Exhibition, Eugenides Foundation. The demonstration is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License. Based on a work at www.sciencetweets.eu.
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Have you ever wondered what exactly the sun does to your skin? Join Trace as he breaks down everything UV rays do to your body. RSVP to our live hangout with NASA happening on August 27th at 4pm PDT: http://dne.ws/VGZusz Read More: These People Had No Clue What The Sun Did To Their Skin http://magazine.good.is/articles/take-care-sunscreen-up “We have a range of terrible excuses for forgetting to put on sunscreen—from being in a rush, to not wanting to get our hands oily (there’s a spray for that, people), to believing that the sun’s rays are entirely blocked when it’s overcast.” VIDEO: Ultraviolet camera shows sun damage hidden beneath your skin’s surface http://www.wxyz.com/news/thenow/video-ultraviolet-camera-shows-sun-damage-hidden-beneath-your-skins-surface “If you could ...
Clipbank video learning resources. Extracted from educational programmes for secondary schools aired on Channel 4. 1. State your skin type and then use the UV-chart to answer the following questions: 2. What levels of risk of skin damage would there have been for you at locations A, B, C, D and E? 3. Explain why someone living in an area where the ozone layer is thinner would be at a greater risk of skin cancer. 4. Which of the following statements are true and which are false? (a) A suntan is healthy. (b) A tan will give you some protection from the sun. (c) You cannot get sunburn on a cloudy day. (d) You cannot get sunburn in the water.
During a water change I was doing some routine filter maintenance on my Sun Sun 304B external canister filter, and I found that the plastic shielding around the UV sterilizing light has worn away and the UV radiation is breaking down the plastic pot scrubbies I use as bio material (biofiltration) in my filter trays.
Optometrists discuss the potentially damaging effects of the sun's UV radiation on your eyes and what you can do to help reduce the risk of damage.
An explanation of the three types of UV radiation: UVA, UVB and UVC. By Cowen Physics (www.cowenphysics.com)
(What does UV radiation do to skin cells?) This Biology 265 video teaches how melanin protects skin cells against UV radiation, and how stretch marks occur.
Clif High IDIR, Magnetic Pole Shift, USA Housing Markets, Earth Expansion, UV Radiation, Clif High IDIR, Magnetic Pole Shift, USA Housing Markets, Earth Expansion, UV Radiation
A variety of cosmic events have both helpful and harmful effects on life on Earth. From the beauty of the Aurora Borealis and rainbows to the dangers of UV radiation and cosmic rays, from the miracle of photosynthesis to the thrill of a meteor shower.
A look at various cosmic phenomena, both "good" – such as the beauty of the aurora borealis, the thrill of a meteor shower, the miracle of photosynthesis, and the "bad" – such as UV radiation that can "get under our skin", and solar flare activity that can not only scramble electronics, but could threaten life on Earth.
LessEMF, NEW TECHNOLOGY TO BROADCAST MP3 MOLECULAR HARMONIC RESONANCE HEALING, MONITOR ELECTROSMOG AND REDUCE IN YOUR HOME AND BUSINESS, TRACK NUKE REACTOR AND FUKUSHIMA RADIATION, UV RADIATION DETECTORS, PERSONAL AND HOME PROTECTION FROM ELECTROSMOG
A variety of cosmic events have both helpful and harmful effects on life on Earth. From the beauty of the Aurora Borealis and rainbows to the dangers of UV radiation and cosmic rays, from the miracle of photosynthesis to the thrill of a meteor shower.
A look at various cosmic phenomena, both "good" – such as the beauty of the aurora borealis, the thrill of a meteor shower, the miracle of photosynthesis, and the "bad" – such as UV radiation that can "get under our skin", and solar flare activity that can not only scramble electronics, but could threaten life on Earth. Subscribe to new videos - https://www.youtube.com/channel/UCmBj2tOxpXZizXgDilTnvig?sub_confirmation=1
UV radiation can cause cancer!! The Ozone protects bio life forms from harmful UV rays, ozone rips move jet streams and this can lead to changes in the climate across the ranges, these changes are not being covered in the mainstream media, ask yourselves why, this is the biggest story of our time and yet most do not have awareness of it, consider supporting this channel and the work that is ongoing here, despite the budget i think i have achieved a mile stone so far, link below to pledge a donation to keep the work going, https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted;_button_id=BABVNBC88VA9Q
A variety of cosmic events have both helpful and harmful effects on life on Earth. From the beauty of the Aurora Borealis and rainbows to the dangers of UV radiation and cosmic rays, from the miracle of photosynthesis to the thrill of a meteor shower. The Universe S04E10 PULSARS & QUASARS - BluRay 1080p https://www.youtube.com/watch?v=n7UNhx49wfw The Universe S04E12 EXTREME ENERGY - BluRay 1080p https://www.youtube.com/watch?v=KfQD3O3Lp0E The Universe S03E10 STRANGEST THINGS - BluRay 1080p https://www.youtube.com/watch?v=iNB2P7V5uC4 The Universe S03E09 ANOTHER EARTH - BluRay 1080p https://www.youtube.com/watch?v=ojwXInq8_rs The Universe S05E01 - 7 WONDERS OF THE SOLAR SYSTEM - BluRay 1080p https://www.youtube.com/watch?v=slIg8FUOKuU
In this VOEE (Voice of Ethiopia in Edmonton) radio program, Dr. Abiy and Semnawork present a special Ethiopian new year program with sensational and lovely cocktails of "enkutatash" Ethiopian music, literature[Alex Abraham's "Yemiyastelelu betsuan nachew" & "Negere kondo"] and poetry [Bewuketu Seyoum's "Feker eske Mekaber"]. Also your favorite science show- unlocking one of the several ways in which the universe is trying to talk to us - UV radiation. UV radiation is one among the spectrum of electromagnetic radiations the universe is trying to communicate to us. Dr. Abiy explains how UV radiation conspires to kill us and tries to save us at the same time. Also discussed, its effect in resulting in Cancer, sunburn and tumours. Happy new year!!! Miss it not!!!! Like, Share and Subscribe my...
http://GeoengineeringWatch.org TO READ OR POST COMMENTS ON THIS VIDEO, PLEASE GO DIRECTLY TO THE ARTICLE http://www.geoengineeringwatch.org/geoengineering-investigation-demanded-by-shasta-county-residents/ On July 15th, 2014, citizens from Northern California rallied to create the largest attendance ever at the Shasta County Supervisors chambers (400+, chairman Les Baugh confirmed this attendance record at the start of the meeting). The primary purpose of this meeting was to present information that proves there is a very dire heavy metal contamination and UV radiation issue across the Shasta County region (and the world). A list of 10 experts presented data to the board to confirm the legitimacy of the concerns being addressed. At the end of the presentation, the board voted unanimously t...