Homework due in class, Nov 27. Remember to show your work, neatly.

1) If a 10^5 kg comet falls from the Oort cloud on a collision course with the Earth and we detect the comet at the distance of Mars, how long do we have before it hits the Earth. How much energy would be released? (4 points)

2) Make a crude estimate of the number of asteriods in the Belt (from either the web lectures or the textbook). Assuming that the typical density of an asteriod is 4 gm/cc and the typical radius is 100 meters, calculate the total mass of asteriods. How does this compare to the mass of the Moon. (4 points)

3) Calculate how fast the Sun would rotate if all the angular momentum of the planets were added to it. (4 points)