I learned this today. There are two ways to work out the age of the universe. The first is to calculate the age of the oldest stars. The second way is to work out how fast the universe is expanding and cooling and extrapolate backwards. The universe is thought to be 17.772 billion years old, […]
#144 How do people know the age of the universe? Read More »
I learned this today. Venus and Uranus spin in the opposite directions to the other planets possibly because Venus flipped over and Uranus was hit by another planet. Our sun rotates anticlockwise, and it takes about 27 days to complete one rotation. Because the sun rotates anticlockwise, all of the planets in our solar system
#142 Why do Venus and Uranus spin the wrong way? Read More »
I learned this today. There is no reason why the speed of light is 299,792,458 m/s. It just is. The speed of light is the top speed that matter or energy can travel at. All forms of electromagnetic radiation travel at the speed of light. Radio waves and electricity, for example. Nothing can travel faster
#129 Why is the speed of light 299,792,458 m/s? Read More »
I learned this today. With the technology we have today a space elevator isn’t possible, but it could be possible in the not so distant future. The main idea for a space elevator would have a cabled anchored somewhere on the surface of the Earth. The other end of the cable would be attached to
#126 Is a space elevator possible? Read More »
I learned this today. A wormhole is a hypothetical tunnel that would connect two separate points in space. Wormholes are hypothetical and have obviously never been discovered. They were first theorized in 1916. Karl Schwarzschild, a German physicist and astronomer started looking into Einstein’s field equations. These are the equations that Einstein used in his
#122 What are wormholes? Read More »
I learned this today. Dark matter is a hypothetical matter in space that doesn’t absorb, emit or reflect light, yet has gravity and keeps the universe together. It is theorized that dark matter makes up 27% of the universe. The part that we can see, the ordinary matter, only makes up about 5%. If dark
#119 What is dark matter? Read More »
I learned this today. Nuclear pasta is a theoretical matter that might exist in the crust of a neutron star. It would be the strongest material in the universe and would be ten billion times stronger than steel. A neutron star forms when a supergiant star collapses. Stars are made up of hydrogen and helium.
#115 What is nuclear pasta? Read More »
I learned this today. The Milky Way Galaxy orbits the barycenter of the Local Group. The barycenter is the center of mass of two bodies that orbit each other. It is the point that they orbit around. The word comes from Ancient Greek and means “heavy center”. When two objects orbit each other, there is
#106 What does the Milky Way Galaxy orbit? Read More »
I learned this today. Light can’t escape from a black hole because of the curvature of space caused by gravity. In physics, gravity is the weakest of the four fundamental forces. The forces are gravity, the electromagnetic force, and the strong and weak forces that exist in atoms. Isaac Newton described gravity as a force
#101 Why can’t light escape from a black hole? Read More »
I learned this today. A Lagrange point is a point of equilibrium where the gravitational forces of two large objects balance out the centripetal force. A third object can remain motionless in a Lagrange point without having to use any power. Centripetal force is the force that acts on an object in a circular motion,
#99 What is a Lagrange point? Read More »
