General Astronomy Quiz 2 Flashcards
What did Galileo explore?
Physics
What did Tycho Brahe survery the sky with?
Nothing, he did not use a telescope
How did Tycho get his own observatory?
By observing a supernova (Tycho’s star) in 1572
What did Tycho’s interests not include?
Mathematical analysis of observations
Who did Tycho hire?
Johannes Kepler, as an assistant
What did Kepler’s analysis lead to?
The three laws of planetary motion
Why did Kepler coin the term “ellipse”
Because circles could not fit the orbital data
What is an ellipse?
a plane curve surrounding two focal points with a semi-major axis (long radius)
What is Kepler’s First Law?
Each planet moves around the Sun in an ellipse, and the Sun is one focus of it
What is Kepler’s Second Law?
The straight line joining a planet and the Sun sweeps out equal areas in equal time
What is Kepler’s Third Law?
p^2=a^3, the square of the planet’s orbital period is proportional with the semi-majore axis of its orbit
What did Isaac Newton create?
New physical interpretations to the mathematical descriptions of astronomy
What law did Newton develop?
The universal law of gravitation
It says there is a force between two masses
Does the acceleration of gracity depend on the mass of a dropped object?
NO
What is the requirement for gravity?
For it to act on an object that has mass, and there’s another object with mass anywhere in the universe
