Quiz me about this topic! Cool fact about this topic! Try this! Give me additional resources! Show me related lesson plans. The electromagnetic EM spectrum is the range of all types of EM radiation.
The other types of EM radiation that make up the electromagnetic spectrum are microwaves , infrared light , ultraviolet light , X-rays and gamma-rays.
You know more about the electromagnetic spectrum than you may think. The image below shows where you might encounter each portion of the EM spectrum in your day-to-day life.
Radio: Your radio captures radio waves emitted by radio stations, bringing your favorite tunes. Radio waves are also emitted by stars and gases in space. Microwave: Microwave radiation will cook your popcorn in just a few minutes, but is also used by astronomers to learn about the structure of nearby galaxies. Infrared: Night vision goggles pick up the infrared light emitted by our skin and objects with heat. In space, infrared light helps us map the dust between stars.
Visible: Our eyes detect visible light. When they look much farther away, radio telescopes show us some of the weirdest objects in the universe. Most galaxies have supermassive black holes in their centers. Black holes are objects that have a lot of mass squished into a tiny space. This mass gives them so much gravity that nothing, not even light, can escape their pull. These black holes swallow stars, gas, and anything else that comes too close.
As it gets closer, it goes faster and faster. Huge jets, or columns, of electromagnetic radiation and matter that does not make it in to the black hole sometimes taller than a whole galaxy is wide form above and below the black hole. Radio telescopes show those jets in action Figure 4. Massive objects like these black holes warp the fabric of space, called space-time. Imagine setting a bowling ball, which weighs a lot, on a trampoline.
The trampoline sags down. Weighty stuff in space makes space-time sag just like the trampoline. When radio waves coming from distant galaxies travel over that sag to get to Earth, the shape acts just like the shape of a magnifying glass on Earth: telescopes then see a bigger, brighter picture of the distant galaxy. Radio telescopes also help solve one of the biggest mysteries in the universe: What is dark energy? The universe is getting larger every second.
But how strong is dark energy? Scientists can use megamasers to pin down the details of dark energy [ 5 ]. If scientists can figure out how far away those megamasers are, they can tell how far away different galaxies are, and then they can figure out how fast those galaxies are speeding away from us. If we only had telescopes that picked up visible light, we would be missing out on much of the action in the universe.
Imagine if doctors had only a stethoscope as a tool. Astronomers use radio telescopes together with ultraviolet, infrared, optical, X-ray, and gamma-ray telescopes for the same reason: to get a complete picture of what is happening in the universe. Photons with more energy are ultraviolet radiation, X-rays, and gamma rays gamma rays have the most energy. Photons with less energy are infrared and radio waves radio waves have the least energy.
One megahertz means one million waves pass by every second. Radio waves from outside the solar system. Nature 32, It is fast enough for anyone on Earth to contact others on Earth in less a second. Radio waves are electromagnetic waves, so is light. The differences between light and radio waves are their frequencies and wavelengths. Wavelengths with different sizes also have slightly different properties. For example, radio waves have a longer wavelength and lower frequencies, so they are less energetic than visible light and that is why radio waves have relatively no effects on human body.
It is also because of their differences in frequencies and wavelengths, radio waves can pass through certain materials that visible light can not. However, when light encounters a thick and opaque material, it is likely to be reflected or absorbed.
That is why, people can use cellular services inside buildings but can not do so in elevators. View all posts by lin The different properties of these types of light also have profound astrophysical implications.
Here is a false-color image of Phoenix. How does it compare to the true-color and space shuttle images on this page? We often use visible light images to see clouds and to help predict the weather. We not only look at the Earth from space but we can also look at other planets from space.
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