Ultra-violet light waves
Ultraviolet waves are beyond the visible violet light on the electromagnetic spectrum, because the pronoun ‘ultra’ means 'beyond' or 'far'. They are transverse waves, with wavelengths between 10 nanometers and about 400 nanometers.
Ultraviolet waves can be very dangerous. They cause sunburn which can lead to skin cancer, although people who live in sunny or exposed places have darker skins as this protects their cells. Ultraviolet radiation can cause normal cells to become cancerous. UV-C rays are the most dangerous, but these are nearly all absorbed by ozone in the earth’s atmosphere, as well as 95% of UV-B waves. Your eyes are very vulnerable and snow-blindness is common - snow reflects the UV radiation instead of absorbing it like other objects.
All stars give out ultraviolet radiation naturally, and we receive most of ours from the sun. We can produce UV rays artificially through electric lamps, sunlamps to give you a tan, germicidal lamps that kill germs, and hot objects in space that also give off the radiation.
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mmmnmThe sun in ultaviolet

We can detect the waves through phototubes, ultraviolet telescopes, satellites including NASA's Extreme Ultraviolet Explorer satellite, photovoltaic cells, and radiometers. The waves might be invisible to our eyes, but some animals, such as bumblebees, crocodiles and small birds can actually see them.
Ultraviolet waves have many uses, including security markings, fluorescent lamps, detecting forged bank notes, disinfecting water and killing off germs. Sunlight is a very good disinfectant because of the destructive quality of the UV waves. They also allow people to study other galaxies and stars through the UV light they emit. The waves cause the body to form vitamin D and help accumulate phosphorus and calcium, which are both needed to keep your bones and teeth healthy.
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mLike the Aurora Borealis on Earth, these auroras are also visible on Saturn, but only under ultraviolet light

How different animals see

Dogs, cats and other small mammals can’t see many colours, and can only detect grey properly. Dogs can also see some blue and yellow, but all these animals rely more on their sense of smell and sound than sight. They have better vision at night, perspective and depth perception than us.
Monkeys, some squirrels, birds, insects, and lots of fish can see quite a good colour range. This helps them tell the difference between ripe and unripe fruit, make themselves look more attractive for mating, and identify their predators. Monkeys are just as prone to colour blindness as humans – in one family there is generally about six different types of colour blindness. Horses are as good at seeing colour as humans; they just can’t see anything that’s right in front of them because their eyes are set so far apart.
Snakes have two pairs of eyes. One can see colour, and the other pair are called vision pits. These eyes detect heat using infrared, which is why this kind of sight is called thermal vision. Sea turtles can see yellow, orange and red, but find it extremely hard to see blue, green and violet, which have longer wavelengths.
By examining the cones in the eyes, scientists can guess at how an animal sees things. A technique called “microspectrophotometry” looks at the visual pigments and photo-sensitivity of the cells. This can be used to see what colours fish can detect.

Insect’s eyes are known for the many lenses covering them, up to 30,000 on each eye. These are called ommatidia and help it detect movement and some colour. Bees, birds and butterflies can see ultraviolet light. Bees use this to look at special ultraviolet patterns on the leaves of flowers to guide them into the flower, and diving birds use it to look underwater. The brains of dragonflies are so fast that everything they see seems to be in slow motion.
Bulls can’t see any colour, and only chase red capes during bull fighting because the object is moving. Prairie dogs and squirrels are red/green colour blind, and sharks can hardly see any colour. Some only see in black and white because they don’t have any retinal cones.
Humans and most animals are colour blind in very low light, but recently scientists have discovered that geckos can tell blue from grey without much light at all. Frogs might also be able to do this. In daylight, pigeons are thought to be one of the best animals on earth at detecting different hues of colour.

Other types of wave

How are they generated?
Stars, super novas, black holes, pulsars, natural radioactive decay, nuclear explosions and lightning
They are generated by machines (such as an X-ray tube) and are naturally given off by stars
Our largest source of visible light is our sun, but other objects give off light too
All hot objects give out infrared radiation. Very hot objects like the sun give out more than cooler ones
Mobile phone, starsand different types of transmitter give out microwaves
Man-made radio waves are generated by a transmitter, but natural ones are caused by stars, sparks and lightning
How are they detected?
Gamma-ray detectors contain densely packed crystal blocks. The ray collides with electrons in the crystal
We use computer technology to generate the images produced by X-Rays
Our eyes can detect these rays. Different wavelengths of light appear as different colours
Night-vision goggles or infrared cameras are used to see the heat coming from living creatures
Geiger tubes and recievers are used to detect these rays
Radio antennas and giant radio telescopes can detect radio waves on earth and in space
How might they be dangerous?
Radioactive (ionizing radiation)
They can damage cells and cause cell mutation
Light is generally harmless, although if there's too much it can result in blindness
Too much infrared radiation can damage or kill cells, but they are more gentle than visible light rays
They can cause cataracts in your eyes, which is a clouding of the lens
Large doses of radio waves are believed to cause cancer, leukaemia and other disorders
What are the main or most significant uses?
Kills cancerous cells and cures some types of cancer
Airport scanners and to see bones in the body
Light allows us to see our surroundings and survive
To look at objects in the dark, to change channels on the TV and for cooking in grills and toasters
Microwaves can be used in microwave ovens, radar and commuications
Radio waves transmit sound, TV signals, and let astronauts talk with the people on earth from the moon

Good work. You didn't stick to the sub-headings but the material is all there. The table is also well constructed.


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