AST101H5 Chapter 6: 6
Document Summary
Recall ch1, the edge of the solar system is about half way to the nearest star. After that, another star becomes the dominant gravitational force. Measure the nearest star"s distance using parallax. Planets like earth = terrestrial planets: mercury, venus, earth and mars. Closer to the sun -> warmed by sunlight. This tells us that these planets have to be at least partially not rock. These planets are made up of rocks + metals. Planets like jupiter = jovian planets. (jove is another name for jupiter: jupiter, saturn, uranus and neptune. Far from the sun -> faint sunlight = cold. Masses are large: 14. 5 to 318 x earth"s mass. Average densities = mass/volume = 1 g/cm3 small. This tells us that these planets are mostly gas and fluids. Then started finding many: quaoar (2002), sedna (2004), makemake (2005), Average densities are medium, roughly 2 g/cm3 medium. Rocky objects: asteroids also called minor planets.
