{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

astro100411

# astro100411 - Astronomy 101 Oct 4th 2011 How Big is the...

This preview shows pages 1–2. Sign up to view the full content.

Astronomy 101 Oct. 4 th , 2011 How Big is the Moon? Angle (in radians) = linear diameter distance The diameter of the Earth is roughly 13,000 km. The diameter of the earth is roughly 4 times larger than the diameter of the Moon. The radius of Jupiter is 10x larger than the radius of Earth. How much larger is the volume of Jupiter compared to Earth? Volume of sphere= 4/3 π R3 1000 times larger. Comparing radii is not the correct way to convey how much bigger one object is compared to another. Greek astronomy and the beginnings of science Greek astronomers: Carefully observed the sky Applied logic and math to formulate hypotheses, make predictions , and then test them with additional observations But, they were also swayed by aesthetics Plato (428 – 348 BC) all natural motion is circular reason is more important than observation strongly driven by belief that there are perfect things in the Universe *one could argue that Plato did a lot of damage; held us back for a long time Aristotle (384 – 322 BC) scientific approach Earth's shadow on the Moon during lunar eclipse is round . Therefore, the Earth is round! Observers see different stars at different locations on the Earth. Also favors round shape. Eratosthenes (276 – 195 BC) Measured the circumference of the Earth as follows: The Sun is at the zenith in the city of Syene at noon on the summer solstice But at the same time in Alexandria, the Sun is at 7º from the zenith.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern