AST 101: Introduction to Astronomy


Spring 2013

Updated 26 January 2013
  1. Discussion 1. 15 February
  2. Discussion 2. 22 February
  3. Discussion 3. 8 March
  4. Discussion 4. 29 March
  5. Discussion 5. 12 April
  6. Discussion 6. 26 April
  7. Discussion 7. 3 May

  1. Discussion 1
    Does Astrology Work?

    Astrology, literally the study of the stars, is an ancient discipline. Astronomy and Astrology have the same roots, but diverged within the past few hundred years. Astrology maintains that the planets (including the Sun and Moon) affect us in subtle ways, and that one can gain insight into one's personality based on the relative positions of the planets at the time of birth. Some maintain that one can use the positions of the planets to predict propitious times to undertake important tasks.

    Adherents of astrology point to the large numbers of practitioners. People are not stupid. How can something that does not work have remained so ingrained in our culture?

    Opponents of astrology point to the lack of any physical cause for the claimed effects. They argue that the Sun signs are 2000 years out of date, and astrology is internally inconsistent in how it deals with planets discovered after the year 1700.

    Based on what you know about science, what you know about astrology, and your personal experience, do you think astrology works?

    If you choose to participate, write a short position paper taking one side or the other. You should make clear what you mean by the phrase "astrology works". Please buttress your case with evidence, or with well reasoned arguments.

  2. Discussion 2
    Is there a conflict between science and religion?

    This is a touchy topic, but one that is very much evident in the world today. Certain scientific topics, such as evolution, or the origin of the universe, touch nerves. Certain religions disavow these concepts. Perhaps the best known science/religion conflict is that of Galileo Galilei vs. the Roman Catholic Church, a topic very germane to our discussion of the history of astronomy and the development of modern science.

    This discussion will start with the mindset of the 17th century as we examine the Galileo affair. Who was right and who was wrong? Why did the parties act as they did? Where the discussion goes from here - that's up to you.

    The question to consider is, "Is there a conflict between science and religion?". If you say no, you can stop there (but explain why you say no). If your answer is yes, then are science and religion equally valid ways of looking at the world, one based in empirical observation and experiment and the other based in faith, each supreme in its own domain? What happens when their areas of expertise overlap? Can they avoid intruding into each other's domain?

    Again, you are free to choose your terms. Please support your position with logical statements and concrete examples.

  3. Discussion 3
    Global Warming. Is it real, is it a threat, and who's to blame?
      There are three issues here.
    • Is the Earth warming abnormally now, or is this current trend normal?
    • If the Earth is warming abnormally, is this a problem?
    • If the Earth is warming abnormally, can we attribute this to an overactive Sun, or to human activities.

    This is a politically-charged issue. There is plenty of data, but the data can be interpreted in more than one way. The web sites listed in the sun web page provide both factual data and different interpretations of the data. The differing interpretations are the problem. We can react. Should we?

    What do you thing? Do you see any compelling evidence one way or the other? Please support your position with logical statements and concrete examples. Please try to avoid political diatribes.

  4. Discussion 4
    Is there a future for life on Earth?

    This is a question that is perhaps better pondered after taking AST 248, but we can take a stab at it.

    As we have discussed in class, the Sun has brightened by 30% over the past 4.5 billion years, and will get brighter still during the next 4.5 billion years. The temperature of the Earth depends directly on the solar luminosity, so the Earth will heat up. There are feedback mechanisms that help maintain a more-or-less stable climate in Earth - witness the "faint young Sun problem". But feedback loops have their limits.

    But over the next billion years or so, the temperature on the Earth is projected to climb to about 373K - the temperature where water evaporates. At this point, life as we know it cannot exist on Earth.

    Your assignment: speculate about the far future. Where will human beings be in a billion years?

  5. Discussion 5
    Is there a role for Man in space?

    Manned spaceflight captures public attention ... sometimes. The 1960s were heady days for manned spaceflight, as within a decade we went from suborbital flights to men on the moon. But once it bacame routine, manned spaceflight lost some of its luster. With the International Space Station, and President Bush's pland to return to the Moon and send men to Mars, the role of men in space is again in the headlines.

    What are the arguments for going into space? Exploration? Manifest Destiny? Scientific discovery?

    Some argue that robots are utimately cheaper, and return great dividends, while human beings just get in the way. Consider that all exploration of the Solar system, with then exception of 7 lunar sites visited by the Apollo astronauts, has been carried out by robotic spacecraft, and that the Hubble Space Telescope is a robotic observatory. On the other hand, when a robot gets in trouble, or faces a novel situation, we appreciate the complexity of the human brain.

    What are the costs, both in dollars and in human lives? Can the costs be justified? Need they be justified?

    Your assignment: argue either pro or con. Support your argument with facts. If you wish to take the position that the money is better off spent here on Earth, remember that no cash leaves the Earth even if it is spent on spaceflight.

    There are plenty of websites that address these issues, often in a very one-sided manner. One organization on the pro side of the issue is the Students for the Exploration and Development of Space. A site that is generally opposed to using space, because of a fear of militarization, is the Global Network against Weapons and Nuclear Power in Space.

  6. Discussion 6
    Are UFOs evidence for visitations by extraterrestrials?

    There are unidentified "flying" objects. The vast majority are actually identified after the fact, or are identifiable, as fairly mundane objects. The object most commonly identified as a UFO is the planet Venus. The term UFO is not, or should not, be synonymous with little green men (or other aliens) in flying saucers.

    That said, not all UFOs have been identified, and there are true believers who are convinced that we are being visited by aliens. This is an extraordinary claim, and extraordinary claims require extraordinary evidence. The general consensus is that such evidence does not exist. But absence of evidence is not evidence of absence.

    Rather than true believers against skeptics, I would like to focus this discussion on the astronomical facts. Is it likely that aliens would come to Earth to watch us? How would they get here (their star must be far away)? Why would they be humanoid?

    In your position paper, please use some of what you have learned to date about the galaxy, and life in the galaxy. Please back any assertions with facts (it isn't enough to say that your aunt was abducted by Greys).

    Ancillary information.

  7. Discussion 7
    Was the universe made, or did it just happen?
    "We had the sky up there, all speckled with stars, and we used to lay on our backs and look up at them, and discuss about whether they was made or only just happened. Jim he allowed they was made, but I allowed they happened; I judged it would have took too long to make so many. Jim said the moon could a laid them; well, that looked kind of reasonable, so I didn't say nothing against it, because I've seen a frog lay most as many, so of course it could be done."
    Mark Twain: Adventures of Huckleberry Finn

    The origin of the universe is an open and, to some, uncomfortable question. There clearly was a beginning. Some argue that this indicates a need for a creator, while others are comfortable with an origin in a random quantum fluctuation in a larger "multiverse". It is clear that there is order to the universe. The universe evolves according to the fairly simple laws of physics. Is this an argument for design?

    We have come full circle, from our second discussion about whether there is a conflict between science and religion, in the context of Galileo and the heliocentric theory, back to the same question in a much more fundamental setting. In this discussion, I seek your opinions. Does investigation of the universe reveal the splendor of the creator, or does it reveal the clockwork of the cold equations of physics, or are the two inseparable? And what is our role in the universe?