- Which of these is a NOT a dwarf planet?
- At what point in orbit will a planet reach its fastest speed?
- Which astronomer was the first to say that the Earth is shaped like a sphere?
- What two factors affect the gravitational pull of an object?
- Which of the following planets has the shortest orbital period?
- The strength of gravity depends on the ________ of the objects and the __________the objects.
- An asteroid with an Earth-crossing orbit is officially called a(n) ______ asteroid
- How many planets (not including dwarf planets) are in the solar system?
- Which astronomer believed that gravity and inertia keep the planets in orbit?
- The sun makes up most of the mass in our solar system.
- What is the eccentricity of a perfect circle?
- An astronomical unit is the distance from the ___________ to ____________
- Which of the following is constant, meaning it does not change based on location?
- Which of the following factors has the greatest influence on the strength of gravity?
- Planets orbit in the shape of an ellipse. Which of Kepler's laws is this?
- As the comet approaches the sun, its ________ will _________.
- An object with a larger mass will have a(n) _________ gravitational force.
- Which astronomer designed a telescope and discovered the moons of Jupiter?
- Before Kepler, scientists thought orbits were ____. Kepler showed that planets' orbits are ____
- Which astronomer altered the geocentric model by adding epicycles to explain retrograde motion?