ASTR Mid-term 1 Flashcards
(15 cards)
If you used a basketball (1 foot diameter) to model the sun, how far away would you need to put a model of the Earth?
about 100 feet
If you used a basketball (1 foot diameter) to model the sun, how large would you need to make a model of the Earth?
a lentil bean (about 1/100 of a foot)
About how many copies of the moon would fit between the Earth and the moon?
120
The sun’s diameter is about 100 times greater than the Earth’s. If you found a red giant star that has a diameter 100 times greater than the Sun’s, then which is the best approximation for the number of Earth’s that could fit across this red giant?
10,000
The suhttps://foothillcollege.instructure.com/files/671017/download?download_frd=1&verifier=lWWr3ciICRRBayzcOCMbQjDMLmOlw42eytiN4jq9n’s diameter is about 100 times greater than the Earth’s. The following images shows a picture of the Sun. The dark spots on this image are sunspots, relatively cool regions on the surface of the Sun. How does the size of Earth compare to the size of the sunspot that has the arrow pointing to it?https://foothillcollege.instructure.com/files/671017/download?download_frd=1&verifier=lWWr3ciICRRBayzcOCMbQjDMLmOlw42eytiN4jq9
Earth and the sunspot are about the same size.
The Milky Way galaxy is about 100,000 light-years across. The closest spiral galaxy, the Andromeda galaxy, is about 2.5 million (2,500,000) light-years away. If you represented the Milky Way galaxy with a CD (or DVD, or Blu-Ray, or some other object about 0.1 meters across), how far away would you need to place a CD representing the Andromeda galaxy?
a few steps away (about 3 meters)
Which of the following observations did ancient people use to try and figure out the structure of the solar system?
Planets appear to slowly move from west-to-east from week-to-week compared to background stars
Planets occasionally appear to move from east-to-west compared to background stars
Which of these best characterizes the process by which humanity came to understand the motion of planets?
Several astronomers each figured out a part of the puzzle, and built on the work of the people who came before them
Which of the following observations is a clue that Mercury and Venus are inside of Earth’s orbit around the sun?
They both always appear close to the sun on the sky
These are all actual discoveries made by Galileo. Which one absolutely proved that the planets do not orbit around the Earth?
Venus sometimes appears like a fully lit circle.
What is happening when a planet outside of Earth’s orbit, like Mars, appears to reverse its direction of motion?
The Earth is passing it
On the left there is an image showing a top-down view of the Earth and Mars, with a schematic of distant stars at the top.
On the right are three views of the night sky with those stars and Mars.
Which one, A, B, or C, shows Mars’ apparent position at this time?https://foothillcollege.instructure.com/assessment_questions/1302168/files/835133/download?verifier=9q0A3GzltwrRGjAK2d2mL9hIUYd92mgdp9DCqpN1
C
Astronomers find two planets orbiting another star. One planet is a gas giant, and it is close to the star. The other planet is a small rocky planet like Earth, and it is far from the star. Which planet will orbit that star in the least time?
the gas giant
If the Earth’s mass was twice as high as it is, how would its orbital motion around the sun be different?
nothing would happen
Which planet in our solar system has an orbital period of 1 year and orbits the sun at a distance of 1 AU?
Earth
