Homework 5

  1. Chapter 12, Problems 1-4 (Page 350)
    1. Surprising. A small asteroid would have little heat left since they cool so quickly and tidal heating isn't likely to provide any heat.
    2. Surprising. Meteorites shouldn't be older thant he solar system.
    3. Surprising. Things in the inner solar system are generally warm enough to lose ices over the age of the solar system. They are also unlikely to form in that location, inside the frost line.
    4. Surprising. Kuiper Belt Objects have a lot of ices to build with, so that's what they'll mainly use for this composition.
  2. Chapter 12, Problem 11 (Page 350)
    Since Barkely is twice as bright as Jordan is in the infrared, it must be hotter than Jordan. To be the same distance from the Sun but hotter requires that Barkely has a lower albedo (it has to absorb MORE of the light that hits it). But wait: how can they be the same brightness in the visible? By making Barkely larger than Jordan so that it has more area to reflect from, overally.
  3. Chapter 13, Problems 2-5 (Page 379)
    1. Sensible. With plate tectonics, former seafloors can be forced upwards into mountains.
    2. Surprising. Plate tectonics is usually very slow. So to move the city quickly enough to subduct it in a few years would be very surprising.
      3. Surprising. Earth's atmosphere has a lot of by-products of biological activity in it. Examples include methane and especially oxygen. There aren't many ways to produce a lot of these gases without organic activity.
    3. Very surprising. It is difficult to make ozone from anything other than molecule oxygen. It's also difficult to keep the ozone from breaking down into molecule oxygen.
    4. Chapter 13, Problem 11 (Page 380)
      1. Whatever they says, as long as it's a feedback process.
      2. As the Sun warms up, Earth will warm. Because more water will be evaporated and more wind will be generated, erosion will increase in rate. This will allow more silicates to react with the carbon dioxide to form rocks. Since volcanism and tectonics don't increase in rate, the source of carbon dioxide won't change so that we will have a net loss of carbon dioxide in our atmosphere, cooling the planet. Since this counteracts the inital change, this is a negative feedback.