Infra-red light waves

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What are they?

IR light (infra-red) light is electro-magnetic radiation with longer wavelengths than visible light.
it was discovered by william herschel in 1800.
over half of the energy that arrives at earth is in IR form

Are they dangerous?

IR radiation carries little danger to humans

Where do they come from?

IR waves mainly come from the sun and fire

How do we detect them?

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we can use cameras to detect them namely thermal imaging cameras

What can they be used for?

IR radiation can be used for thermal imaging which allows us to see the temperature of objects due to the amount of heat radiated

Geostationary satellites

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what is a geostationary satellite

A geostationary satellite is on a line of sight with about 40 percent of the earth's surface.
Three such satellites, each separated by 120 degrees, can provide coverage of the entire planet.
they orbit at 35,800km they make one orbit every 24 hours.

In the table below, fill the cells with very brief notes. Use the other pages to gather the information from, and you may want to go outside of this wiki if you really can't find the information here (though I'd be surprised!).

How are they generated?
stars, super novas, black holes
An X-Ray tube
the sun
uv lights
hot things
luminescent th
large stars,mobiles
How are they detected?
changes in densely packed crystals
Satellites or image receptors
filtrate, UV detector
our eyes, camera
receivers in mobile phones
How might they be dangerous?
can give give you cancer
cancer, sun burn
What are the main or most significant uses?
can cure cancer
To scan for bone breaks or in dentists
to kill bacteria
for food in microwaves and in mobile phones
transmitting sound

Good effort - but I think there is more material out there to find!
The table is complete but, again, it could enjoy a bit more information.

Overall, well done!

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