Before I tell you a what dark matter is, let’s figure out what dark matter isn’t. Dark matter is not just clouds of normal matter without stars because it would admit particles that were detectable. Dark matter can’t be anti-matter either because anti-matter produces gamma rays when it reacts with normal matter. Dark matter can’t be made of black holes either because it would violently affect objects. The idea of dark matter was formed because as the scientist applied the laws of gravity to how fast nearby galaxies were rotating, nothing made sense. Which resulted in them thinking there must be missing matter. There must be invisible matter, there must be dark matter,
What is dark matter?
To be honest, nobody knows. But we do know something is there. Something is interacting with gravity, & there’s a ton of it. Dark matter is most likely made out of some complicated exotic particle that interacts with space in a way that doesn’t admit or absorb light or electromagnetic waves.
Dark Matter History
The idea of Dark Matter was first mentioned by Fritz Zwicky, he was always looking at clusters of galaxies and one day he realized, the galaxies are moving so fast that they should fly apart. He measured how fast the galaxies were moving around each other, and with this information he estimated their mass. When he compared the observable mass to the non-observational mass he found it was 400 times larger meaning there most be invisible mass.
With this knowledge he was able to deduct that something must be holding them together. In one of his writing he called this mysterious observation dunkle Materie which translates to Dark Matter.
Forty years later a woman named Vera Rubin entered the science field with the same bizarre idea. The stars are moving so fast they should fly off. She believed that there must be a gravitational pull from something that's not bright.
Gravitational Lensing Dark Matter
Stars orbiting galaxies superfast and not falling apart, isn't the only reason we believe dark matter is real.
Gravitational lensing supports the idea of Dark Matter. This is when light bends around massive objects as it travels through space, the gravitational pull from objects can distort or bend the light., the bigger the object the more the light bends.
Why is Dark Matter called Dark Matter?
The name dark is due to the fact that it doesn’t shine, absorb or reflect light or any electromagnetic fields or radiation. Dark matter is completely invisible.
Dark Matter vs Dark Energy
Dark matter produces gravity & dark energy produces anti-gravity. Together they make up 95 percent of the Universe. Feel smaller? Anyways, dark energy is what is causing space to expand & is the same reason we are becoming farther & farther from other galaxies, except for Andromeda in several billion years both of our galaxies will become one.
What is Dark Energy in simple terms
Dark energy is simply just a name that was given to the mysterious force that is causing our universe to expand. In the 1990s by looking at supernovas astronomers discovered that outer space is expanding and accelerating it is so fast that not even the big bang could have set this in motion.
Why Do We Think Dark Energy is Real?
In Albert Einstein's view of space-time is just mesh that is dormant unless energy or matter bends it. Meaning that there must be a non-measurable force causing space to expand.
Dark Matter is the Santa of Space
Space Christmas Jingle
“He hears you when you're sleeping, he knows when you're awake, he keeps your galaxy together, so be good for goodness’ sake. Oh! You better not shout, you better not cry, you better not pout I'm telling you why, dark matter is holding your galaxy together.”
Dark Matter may not be real. But we think Dark Matter is made out of some complicated exotic particle that interacts with space in a way that doesn’t admit or absorb light or electromagnetic waves.
Dark Matter was discovered by Fritz Zwicky
Dark Matter must exist because of gravitational lensing, this is when light appears to be bent.
Dark Matter is called Dark Matter because it admits no light, and doesn't appear to interact with magnetic fields.
Dark Matter produces attraction & dark energy results in expansion. Fun fact:eventually we won't be able to study other galaxies because they will be too far away.
Dark Matter must be real because something must be holding our galaxies together, if there was nothing there, our galaxies would fall apart.
We think Dark Energy is real because in order for an object in space to move it needs energy or matter, but objects are becoming faster, but there is no visible energy or matter.