The Darkness in the sky at night.
A Dark Welcome
Hello and welcome to dark matter central. We will be talking about Dark Matter. I bet when you hear that you might think it is probably this dark magic, but you are wrong! If it's night time right now you should go outside and look up - yes up. Do you see it? It's the darkness in the sky!
What Is Dark Matter?
Dark matter is not always easy to understand. It is a substance that exists that we cannot see. It seems very dark, but it is invisible. In space, it looks like a dark cloud. Sometimes you can see the stars in front of it, but the blackness behind the stars is dark matter.
How Do We Know Dark Matter Exists?
The only way we have come to know about Dark Matter is by observing the Universe. Scientists can see galaxies rotating, and they know how much gravity is needed to hold them together. The faster the galaxy rotates, the more gravity it needs. The only way to have more gravity is if the galaxy has more mass. When the scientists calculated how much mass the galaxy had, it wasn't enough for how fast the galaxy was rotating. That is when the scientist realized there must be matter that we cannot see.
Size of Dark Matter
Dark matter can be any size. It can be bigger than galaxies or be smaller than a grain of sugar.
What Else Do We Know About Dark Matter?
The Universe is about 5% normal matter, 27% dark matter, and 68% dark energy. Dark matter is a substance that we aren't sure what it is made of. Dark Matter does not reflect light and it does not absorb light.
Dark Matter in the Universe
There are several theories of the structure of the Universe such as Flat, Open, or Closed. Flat is where it has 180 degrees and the further it expands, the slower the expanding goes. It also has a very small density. Open is where it curves like a saddle and is less than 180 degrees. Closed is a sphere and extends further than 180 degrees. Scientists think that Dark Matter has an affect on the structure of the Universe.
An Artist's Drawing of Dark Matter If We Could See It
A Galaxy Held Together with Dark Matter
Come To Dark Matter
You can come here 24/7 because dark matter is everywhere in space!