Answer Happy

1. Most comets are thought to have originated in either the Kuiper belt or the Oort cloud. An object orbiting in one of these regions that has a close encounter with another such object can be deflected by the gravitational interaction so that its orbit becomes much more eccentric than before; in this case it may end up with an aphelion close to its original distance and a perihelion much closer, possibly less than 1 AU. a. If a comet has an aphelion distance near the middle of the Kuiper belt at 40 AU and a perihelion distance of 0.5 AU, what would its period be in Earth-years? (2 pts) Recall the two versions of Kepler's 3rd law that you used on the previous homework: a = √P² or P= 3 b. What would a comet's period be if it had an aphelion distance at the inner edge of the Oort cloud (2000AU)? (2 pts) C. Based on the answers above, does it seem more likely that Halley's comet (with a period of 76 years) originated from the Oort cloud or the Kuiper belt? (2 pts) d. Halley's comet has an orbit that is very highly tilted with respect to the ecliptic and also retrograde, meaning that it orbits the Sun in the opposite direction from the planets. From what you know about the shapes of the Kuiper belt (mostly flat in the plane of the ecliptic) and Oort cloud (more or less spherical), does this seem to agree with your answer to part c, or does it complicate things? (2 pts)