UV photons have the right energies to cause chemical changes. These DNA lesions are called thymine dimers. Your body has several strategies to repair cell damage, but occasionally the repair is not done correctly and a mutation results. An accumulation of mutations can make the skin cell malignant; resulting in cancer. If the damage is too great, the cells just die.
That's what happens when you suffer severe sunburns. The outer layer of skin dies and a new layer must grow back. The ultraviolet region is commonly divided into UVA with wavelengths from to nanometers a nanometer is a billionth of a meter ; UVB from about to nanometers; and UVC from about to nanometers. By comparison, visible light has wavelengths from about to nm. However, some UV light does reach the surface and can cause skin damage.
You should avoid excessive exposure to UV light, whether from the sun or a man-made source, to protect your skin. There are two methods of protection from UV. The color of this light can reveal what type of atom was excited. Green light indicates oxygen at lower altitudes.
Red light can be from oxygen molecules at a higher altitude or from nitrogen. On Earth, aurorae around the north pole are called the Northern Lights. The Hubble Space Telescope captured this image of Jupiter's aurora in ultraviolet wrapping around Jupiter's north pole like a lasso. This unusual false-color image shows how the Earth glows in ultraviolet UV light. The part of the Earth facing the Sun reflects much UV light and bands of UV emission are also apparent on the side facing away from the Sun.
These bands are the result of aurora caused by charged particles given off by the Sun. They spiral towards the Earth along Earth's magnetic field lines. Ultraviolet Waves. Retrieved [insert date - e. Science Mission Directorate. National Aeronautics and Space Administration.
Bees, along with some birds, reptiles andother insects, can see near-ultraviolet lightreflecting off of plants.
Bug zappers attractinsects with ultraviolet light to lure themto the trap. What is UV Light? The plasma is seen flowing along a magnetic field. Credit: NASA ozonewatch. Johann Ritter's experiment was designed toexpose photographic paper to light just beyondthe visible spectrum and prove the existenceof light beyond violet—ultraviolet light.
Credit: Troy Benesch. In schools one would have learned about light and the prism and rainbow. Starting from Violet and ending in Red. Vibgyor is the visible range. But there are invisible range after Red and after Violet. Those after or beyond vioet are caleed Ultra violet-meaning beyond violet.
UV is not visible. Sunlight or ordinary light has UV in it, but not recognised or visible. UV lamps are used for special purposes like, fake currency note detection, water purifier,sanitation, insectocutor lamps etc. Too much exposure of UV light is damaging to our eyes. That is why the people in tropical areas where sunlight is more, get cataract of the eye more. Usually we cannot look at the sun in normal times as the infra red heat prevents us from looking so.
But during solar eclipse, due to the lack of heat, we tend to look at sun for more time. Hence it is advised to wear proper uv protection to view eclipsed sun. Points: 2. The visible light lies in this range from red to violet. The invisible light lies beyond red and violet. The light which lies beyond red is called 'infrared light' while another beyond the violet is called 'ultraviolet light'.
These both the types fall in invisible category. The ultraviolet rays are widely used in day to day purposes like water purification, fake currency detection.
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