Is it a map of the observable universe? Is it the big bang? Very unclear
In: Planetary Science
You know how iron glows red then white when it gets really hot? It is emitting electromagnetic radiation with wavelength proportional to its temperature. So the hotter it gets, the shorter the wavelength it emits (longer wavelength = lower energy, shorter wavelength = higher energy). This is why it goes from red to white. Now, this doesn’t just happen with iron and metal, literally all matter emits radiation that is proportional to its temperature. This radiation is only in the visible spectrum when its really hot, but warm bodies and objects emit radiation in the infrared range (longer wavelength than red), which is how infrared night vision works, you are literally seeing “heat”. This phenomenon occurs all the way across the electromagnetic spectrum. Cooler bodies emit longer wavelength radiation. When the universe was young, it was very hot and likely very “bright”, but as it expanded and cooled the radiation it emitted shifted from visible light to infrared eventually all the way down to microwave radiation, which is what we see in every direction that we look in the universe today.
Latest Answers