Author Question: Discuss the discoveries of Galileo Galilei as reported in his bookSidereus Nuncius(The Starry ... (Read 76 times)

cmoore54

  • Hero Member
  • *****
  • Posts: 568
Discuss the discoveries of Galileo Galilei as reported in his bookSidereus Nuncius(The Starry Messenger).
 
  What will be an ideal response?

Question 2

How did Copernicus's model of the Universe describe retrograde motion?
 
  What will be an ideal response?



cam1229

  • Sr. Member
  • ****
  • Posts: 329
Answer to Question 1

Galileo was the first person to observe the sky carefully through telescopes and apply his observations to the main theoretical problem of the day-the place of Earth. What Galileo saw through his telescopes was so amazing that he rushed a small book into print,Sidereus Nuncius(The Starry Messenger). In that book, he reported two major discoveries about the Solar System. First, the Moon was not perfect. It had mountains and valleys on its surface, and Galileo used the shadows to calculate the height of the mountains. Aristotle's philosophy held that the Moon was perfect, but Galileo showed that it was not only imperfect but was even a world like Earth. Second, Galileo's telescope revealed four new planets circling Jupiter, planets that we know today as the Galilean moons of Jupiter.

Answer to Question 2

In Copernicus's model, Earth moves faster along its orbit than the planets that lie farther from the Sun. Consequently, Earth periodically overtakes and passes these planets. Imagine that you are a runner on a track moving along an inside lane. Runners well ahead of you appear to be moving forward relative to background scenery. As you overtake and pass slower runners in outside lanes, they fall behind, seeming to move backward for a few moments relative to the scenery. The same thing happens as Earth passes a planet such as Mars. Although Mars moves steadily along its orbit, as seen from Earth it seems to slow to a stop and move westward (retrograde) relative to the background stars as Earth passes it. Because the planets' orbits do not lie in precisely the same plane, a planet does not resume its eastward motion in precisely the same path it followed earlier. Instead, it describes a loop with a shape depending on the angle between the two orbital planes.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question

cmoore54

  • Hero Member
  • *****
  • Posts: 568
Both answers were spot on, thank you once again



cam1229

  • Sr. Member
  • ****
  • Posts: 329

 

Did you know?

Since 1988, the CDC has reported a 99% reduction in bacterial meningitis caused by Haemophilus influenzae, due to the introduction of the vaccine against it.

Did you know?

The highest suicide rate in the United States is among people ages 65 years and older. Almost 15% of people in this age group commit suicide every year.

Did you know?

Approximately one in four people diagnosed with diabetes will develop foot problems. Of these, about one-third will require lower extremity amputation.

Did you know?

Every flu season is different, and even healthy people can get extremely sick from the flu, as well as spread it to others. The flu season can begin as early as October and last as late as May. Every person over six months of age should get an annual flu vaccine. The vaccine cannot cause you to get influenza, but in some seasons, may not be completely able to prevent you from acquiring influenza due to changes in causative viruses. The viruses in the flu shot are killed—there is no way they can give you the flu. Minor side effects include soreness, redness, or swelling where the shot was given. It is possible to develop a slight fever, and body aches, but these are simply signs that the body is responding to the vaccine and making itself ready to fight off the influenza virus should you come in contact with it.

Did you know?

Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.

For a complete list of videos, visit our video library