weight = mass x acceleration
force (newtons) = mass x acceleration
weight- the force due to gravity measured in newtons
dark matter- material in space which is hard to detect
Oscillating theory- The theory that suggests the creation of this universe was followed by the death of a previous one in a repeating process
Steady state theory- Theory that universe expands
Velocity- Speed in a certain direction.
A persons weight is six times less on the moon as there is little gravity.
Planets do not create their own light they reflect light from the sun.
An asteroid is made of rock, tens or thousands kilometers across and believed to have been made from first four planets formed and leftover rock
A comet is made of ice and dust and has an elliptical orbit.
Gravity keeps planets in orbit
After being in space for long periods of time, your bones and heart become weaker (less gravity) because they don't need to work as hard as they do on earth. When they come back they are very weak. Astronauts exercise lots to reduce these effects.
Cosmic radiation- This is high speed protons. They carry a lot of energy and damage human tissues. Continuing damage over a long time can affect…