ASTRO-WIA-3 - Astronomy Assignment #3 Due week of 2/8 -...

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

View Full Document Right Arrow Icon
Due week of 2/8 - 2/12 Please write neatly and show all work Question 1: Elliptical Orbits As Prof. Helfand explained in lecture, planetary orbits are actually ellipses. We compare an ellipse to a perfect circle by stating its eccentricity – a measure of how far from circular it is. Eccentricity is denoted by the letter e and can vary between 0 and 1 (e.g., the Moon orbits the Earth in an elliptical orbit with e = 0.05). This means that there will be a point in the Moon’s orbit when it is closest to the Earth and a point when it is farthest away. We call these points pericenter and apocenter , respectively. Due to its orbital eccentricity, the moon will actually be brighter and appear larger to us when it is at its pericenter as compared to apocenter. A) How much brighter will the full moon appear if it occurs at pericenter versus apocenter? (HINT: Refer to Prof. Helfand’s first lecture for the definition of brightness via the inverse square law. You do not need to know the actual brightness, this is just a comparison.) SUN Mass = 1.99 x 10 30 kg Diameter = 1.39 x 10 6 km EARTH Mass = 5.97 x 10 24 kg Diameter = 12756 km MOON Mass = 7.35 x 10 22 kg Diameter = 3476 km
Background image of page 1

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

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 5

ASTRO-WIA-3 - Astronomy Assignment #3 Due week of 2/8 -...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online