Orbits
An orbit is the path an object in space travels around another. Lots of objects in the Universe orbit others. The Moon orbits the Earth.
- Why do orbits happen?
Orbits happen because of gravity and something called momentum. The Moon's momentum wants to carry it off into space in a straight line. The Earth's gravity pulls the Moon back towards the Earth. The constant tug of war between these forces creates a curved path. The Moon orbits the Earth because the gravity and momentum balance out.
Johannes Kepler
Occupation
Astronomer, Mathematician, Scientist, Teacher
Year born
1571
Research Areas
Planetary motion, Optics, Geometry
- Early Life
Johannes was born in Weil der Stadt (now part of Germany). He had an interest in astronomy from a very young age. When he was 6, his mother took him up to a high place to see the Great Comet of 1577. When he was 9, he was called outdoors to see a lunar eclipse. His family were poor, but Johannes got a scholarship to study at the University of Tübingen.
Nicolaus Copernicus
Occupation
Astronomer, Mathematician, Clergyman
Year born
1473
Research Areas
Planets, Mechanics
- Early Life
Nicolaus was born in Thorn, Poland. His father, who sold copper, died when Nicolaus was 10. After his father's death, Nicolaus’ uncle looked after him and made sure he had a good education.
When he was 23, Nicolaus went to Italy to study law. In Italy, he stayed with a maths professor and became interested in astronomy.
Calculate the Speed of the Planets
Did you know the Earth is travelling around the Sun at nearly 107,000 kilometres per hour?
Interactive Orrery
An Orrery is a moving, mechanical model of the Solar System. It shows how all of the planets orbit around the Sun.
Kepler's Laws: Find the Mass of the Sun
Many years ago, a mathematician named Johannes Kepler created a set of rules explaining planets' movement in our Solar System.