Astro 120: Fall 2005
Fall 2005 Review Sheet
Review Sheet 3
Exam 3 is December 12 at 4:30pm
The final exam is partly comprehensive - about half of the exam will
cover material since Exam 2 half from the first two parts of the course.
Be sure review the eariler material as well as that on
Comets, the Sun, Solar System History, and Life in the Universe
Astrology and Pseudoscience
- Fundamental ideas of astrology.
- Requirement for new unknown force.
- Testing astrology in a fair and rigorous way.
- Results of in-class experimet with sun-sign astrology.
- Results of more stringent experiments.
- Themes of pseudoscience; examples and how to tell
pseudoscience from objective science.
- The structure of the cometary nucleus and its immediate surroundings.
- The coma of a comet and what its made of.
- The formation and nature of the ion (plasma) and dust tails of
- Short period comets and long period comets.
- Periodic and nonperiodic comets.
- The origin of comets in the Oort cloud and Kuiper belt.
- Famous comets (Halley and Encke's comet).
- Clues to the formation of the solar system.
- Observed parameters of the Sun: temperature, size, luminosity.
- The solar photosphere, chromosphere and corona.
- Granulation, sunspots, prominences, flares.
- Sunspots, magnetic fields and the 22 year sunspot cycle.
- Energy generation in the Sun via nuclear fusion.
Formation of the solar system
- Collapse of the sun and solar system out of a molecular cloud.
- Gravitational collapse
- formation of a disk.
- Formation of planets in the solar nebula via
- planetessimal formation
- Temperature distribution in the solar nebula
- The'frost line' and formation of icy vs. rocky planets
- Time scale for planet formation was short (<<100 million years)
compared with the age of the solar system.
Other Solar Systems
- Observational challenge of finding planets around other stars
- Planet detection methods based on 'wobbling' of stars under gravitational
influence of surrounding planets.
- The radial velocity technique as the most prolific.
- Discoveries over the past decade of > 150 planetary systems
- the 'Hot Jupiter' issue
- Questions arising from these discoveries (i.e. is our solar system typical?)
Life in the Universe
- The probability of life on other planets - assumptions and guesses.
- Drake's estimator of the probability of finding a technological
civilization in the galaxy.
- Astronomical, biological, and sociologicaly factors.
- The habitable zone - liquid water and the development of life.
- Likely values for each factor in the Drake Equation.
- Which terms in the Drake "equation" are more certain, which are not.
- The Search for Extra-Terrestrial Intellegence (SETI).
- Methods used by SETI in the search for artificial signals from space.
- Why radio waves are a good way of transmitting signals across the
- Current searches and results.
- Future prospects