They are widely used in astronomy wavelength infrared.
In the picture we can see, thanks to the infrared, what the eye can not see (the eye) from the center of our galaxy. A photo taken by NASA through the Hubble and Spitzer telescope that gives us the idea of the amount of current, just in our own galaxy celestial bodies.
As I said occasionally, infrared or infrared radiation (because light is a form of electromagnetic radiation) as good wave has a length greater than the visible spectrum (for us) and a little dwarf the microwave They warm us breakfast. From 0.7 to 1000 microns.
The good thing about the electromagnetic radiation is to be divided into electromagnetic and thermal radiation, which indicated the physical heat also behaves like a wave (as this is and which we will see shortly, very interesting developments).
In astronomy use it is very important because the interstellar matter intensely radiates infrared, such as cosmic dust. Although gases (hydrogen, helium) absorb visible light well enough (for us), emitting infrared is not absorbed by them for allowing us to see inside the dark clouds of dust. And like all issues in this spectrum (up dust grains a micron to a star, through an entire planet), they allow to see where they have not seen before very definition.
Also, because according to a certain specific material reflects infrared length, it allows to know the composition of the cloud in question. Come on, that lets us know that things are made.
Infrared radiation is very important in astronomy, as well as neutrino detectors, allowing us to observe, also by the color, the time you have what we are observing. That is, the color of the infrared and the object we are seeing also varies with the time you have, moving toward the red and thus can measure the distance that is about us. Come on, it’s a measuring stick.
With neutrinos passing a different thing, which, as can not be absorbed by anything, those who have been expelled forever traveling and traveling. Fortunately, at the time of the big bang, neutrinos were generated there could not be absorbed by the other elements that were creating what we now even can see, calculate and display, making neutrinos at that time to map the beginning of the universe.