ASTR Midterm (1)

1. (2p) In this class you learned about the internal structure of Earth , even though humans were only able to drill down just 1-2% of Earth’s radius. How do we know the internal structure of Earth ? This is done by studying waves of energy that travel through the earth’s core called seismic waves. 2. (2p) Scientists determined the mass of planets a long time ago, way before the space age. For example, the mass of Jupiter is about M Jupiter = 1.9 × 10 27 kg , and the mass of Mars is about M Mars = 6.4 × 10 24 kg . EXPLAIN how the scientists were able to determine the mass of the planets in the Solar System way before the space age. This was done by studying the orbits of the planets in the solar system and how they affected each other, then analyzing why and determining how by measuring the changes made by the power of the neighboring planets’ attraction strength. 3. (a) (1p) Mars is an example of a planet that has seasons pretty similar to the seasons on Earth. EXPLAIN why are there seasons on Mars . This can be explained similarly as to why the earth has seasons. Due to its rotation speed, orbiting path, slight axis tilt, and distance from the sun, Mars experiences 4 seasons of different temperatures. (b) (1p) Jupiter has no seasons to speak of. EXPLAIN why . Because of Jupiter’s distance from the sun and slight tilt, the seasons appear to share no differences, as if it does not have seasons. 4. (2p) In this Astronomy class you learned about the components of the Solar System : the Sun , terrestrial planets , giant planets , moons , dwarf planets , asteroids , comets , and cosmic dust . You also learned that the age of the Solar System is 4.5 billion years . NAME the component(s) of the Solar System which helped us to determine this age. EXPLAIN why the named component(s) could be used to get the age of the Solar System . As we discussed early in this course, scientists study meteorites and determined their age by a process called carbon dating. Meteorites are considered to be the oldest accessible spacial bodies in our solar system. 5. (2p) EXPLAIN why Pluto is a dwarf planet and not a “ regular ” planet. Pluto is a dwarf planet because it does not meet the three criteria created by the International Astronomical Union. That criteria would be it needs to orbit around the sun, clear the neighborhood around the orbit, and lastly would be to have a mass to assume hydrostatic equilibrium. Pluto does not have the second one listed. 6. (3p) In this Astronomy class you heard many times that our planet, Earth, is