Solar System Discoveries Flashcards
How has Copernicus contributed to our understanding of our Solar System?
Copernicus is credited with his heliocentric theory which shows that the Earth, along with the other planets, orbits the Sun.
What formulae do you use to calculate the relationship between a planets distance from the Sun and its orbital period?
T squared= R cubed
T is in years and R is in AU.
How has Galileo contributed to our understanding of our Solar System?
His first major discovery was that Jupiter possessed four large satellites which were later called the Galilean Moons (Callisto, Europa, Ganymede, Io).
He also found that the Moon had an uneven and rugged surface of craters and mountains.
Venus was seen to show phases like the Moon.
How was Ceres discovered?
In the early 1800s, Astronomers looked for a planet between Mars and Jupiter. Giuseppe Piazzi observed an object he thought was at first a comet. Further observations confirmed it as a body orbiting between Mars and Jupiter but it was too small to be classified as a planet and so for years was considered a ‘minor planet’.
How was Uranus discovered?
William Herschel discovered Uranus from Bath in 1781. Astronomers had observed it previously but mistaken it for a star. Further observations from him and others confirmed it as a planet.
How was Neptune discovered?
Scientists were unsure about some small changes in the orbit of Uranus. They theorised that another large body was changing its orbit. John Couch Adams and Urban le Verrier produced calculations of its orbit independently of one another. Le Verrier sent his calculations to the Berlin Observatory where Johann Galle and Heinrich D’Arrest observed it telescopically on the same day.
Why is gravity the force responsible for maintaining orbits?
The Moon doesn’t fall to Earth because it is moving around Earth really fast. If the Earth disappeared it would move in a straight line until it was disturbed by another body.
Newton thought that if you fired a cannonball off a cliff it would eventually fall to Earth but if it was fast enough it would continue on and on travelling through the sky and orbit the Earth.
What is the inverse square law?
Newton proposed the Inverse Square Law. If say we have a half-mass Earth, it would produce a gravity of not half but a quarter (the square of 2). If it was three times as close to the Sun as Earth it would get not 3 times as much light but 9 times as much (the square of 3 is 9).
How has Tycho contributed to our understanding of our Solar System?
Tycho is credited for making accurate observations and careful measurements and was known as the last great naked eye astronomer. He was also known for observing a ‘new’ star - a supernova in Cassiopeia.
How has Kepler contributed to our understanding of our Solar System?
Kepler was credited with his following discoveries:
- Planets move in elliptical orbits around the Sun.
- Planets move faster the nearer they are to the Sun.
- There is a relationship between the distance of a planet and the time it takes to orbit the Sun.
