Author Question: Discuss the discoveries of Galileo Galilei as reported in his bookSidereus Nuncius(The Starry ... (Read 72 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?

Limit intake of red meat and dairy products made with whole milk. Choose skim milk, low-fat or fat-free dairy products. Limit fried food. Use healthy oils when cooking.

Did you know?

GI conditions that will keep you out of the U.S. armed services include ulcers, varices, fistulas, esophagitis, gastritis, congenital abnormalities, inflammatory bowel disease, enteritis, colitis, proctitis, duodenal diverticula, malabsorption syndromes, hepatitis, cirrhosis, cysts, abscesses, pancreatitis, polyps, certain hemorrhoids, splenomegaly, hernias, recent abdominal surgery, GI bypass or stomach stapling, and artificial GI openings.

Did you know?

As many as 20% of Americans have been infected by the fungus known as Histoplasmosis. While most people are asymptomatic or only have slight symptoms, infection can progress to a rapid and potentially fatal superinfection.

Did you know?

There are immediate benefits of chiropractic adjustments that are visible via magnetic resonance imaging (MRI). It shows that spinal manipulation therapy is effective in decreasing pain and increasing the gaps between the vertebrae, reducing pressure that leads to pain.

Did you know?

If all the neurons in the human body were lined up, they would stretch more than 600 miles.

For a complete list of videos, visit our video library