Whenever the subject of mosquito control comes up, someone gives a fervent argument for installing purple martin houses and bat houses. Stores that cater to bird enthusiasts often tout the purple martin houses as the best solution for keeping your yard mosquito free.
A short period comet is conventionally defined as a comet having an orbital period of less than 200 years. What is the maximum possible aphelion distance for a short period comet with a perihelion of 0.5 AU? Where does this place the comet relative to the outer planets? (3)
The short-period comets are thought to originate in the Kuiper Belt, an area outside Neptune's orbit (from about 30 to 50 AU) that has many icy comet-like objects. The long-period comets tend to have orbits that are randomly oriented, and not necessarily anywhere near the ecliptic. They are thought to originate in the Oort cloud.