Final Exam:  Dec 8, 1999 at 9:00-11:00 a.m. in Annenberg G15

The First Lecture

First, Astronomy is probably the oldest science. Anybody who has looked up at the sky has gazed in wonderment.  Driven both by curiosity and religion man continued to study the sky.  There were some pretty important religion-based questions that were addressed such as exactly where did man and the earth stand compared to the universe. On the curiosity side, we are simply driven on and to learn more even as we learn more. For, as we delve in to the limitless universe it seems we often uncover new questions as we answer old ones. The growth in our knowledge of physics in the past 100 years has allowed to to understand a great deal about the stars, planet, galaxies and the universe at large. In the distant past when this knowledge wasn't available astronomers functioned more as astrologers. Where exactly was Mars, etc? The concept of supernatural beings and how these beings may exist and focus attention on the Earth, has affected people's connection with organized religion and vice versa.

The knowledge of astronomy was useful for debates in this area.  The Copernican revolution was a classic example. Now we enter a new era of astronomy and astrophysics where billions of dollars are spent every year on astrophysics research and society as a whole is starting to ask tough questions such as: Why is this research necessary? What's in it for me? Why do I find it interesting? And is it worth that much money?  This has placed a requirement on the professional astrophysicist to emphasize research that connects directly to the interests of the layman rather than, perhaps, the esoteric interests of the peer group of astronomers and astrophysicists who know enough to ask detailed questions.  You, as future leaders and taxpayers will have to answer the question of how much funding to give to astronomy and astrophysics and why. Two of my goals in this course are to motivate you to want to learn this material and to teach you enough so that you will be able to make educated choices about future funding as well as to appreciate future press releases and discoveries.

There is another reason for you to take this course, however, and that is to learn how to think like a scientist. So stop to think a minute now, what does it mean to you when the TV reporter says "today scientists have announced the discovery of..." The use of the word scientist had a certain implied reliability, right? Why is that? And why do most universities require that you take an science class?  This is because you are supposed to receive some training to behave like a scientist, right? Yet mostly the astronomy, biology and geology courses that are offered are descriptive courses where the main goal may be to teach jargon and facts. The facts will be useful as noted above, but beyond that this new knowledge will make you more conversant, and if your child asks you something about the sky someday you'll be able to give concrete answer. But is this motivation enough to require that you take a science class? Probably not. The best reason is for you to get some training at acting scientifically. We won't be able to do this rigorously, but I hope you will actually benefit from this class and that there is benefit is doing the home work the "lab sessions and the observing sessions.

Here are some of the things that I hope will stick with you:

(1) Be methodical and take careful notes: since this is the is the art of  making reproducible results, e.g if you tell somebody exactly how you did  something, they should be able to repeat it and get the same result.  As an aside here, there is implied a certain level of competency in being able to reproduce the results. I could get a very precise ski lesson and still not be able to make it down a snow covered slope in one piece.  Nevertheless, detailed recording of how the measurements, was done, the material was made, etc., is what is needed. And one of the things that makes most of us disbelieve in UFOs, leprechauns, Bigfoot etc, is that the supposed observations are not reproducible in any controlled fashion. (Sure people continue to **report** UFOs, Bigfoot etc), but there is no concrete, reproducible evidence of these things.

(2) Think deductively and critically. For example if a marketing person calls you and tells you if you follow her advice, you will become rich... Think about it...Why doesn't the person on the end of the line just follow her own advice? OR thinking critically: a football payer a few years ago had sore back and the team had him take **40** Advils a day. What was he thinking? Didn't the read the bottle for directions? Also when somebody provides you with a fact that is important to you, how do they know? What is their reference or how did they make the measurement. This method of questioning will even allow you to pick out exaggerated claims such as "Scientists discover Black Hole....''. How did they **know**?

(3) Avoid as often as you can qualitative thinking and descriptions versus quantitative descriptions, e.g. it's a long way to Tipperary...  what does a  "long" way mean?

(4) Always have an idea of where you are going, why are are going there and a schedule for achieving those goals.  No scientific project that takes more than a few hours or days can be done on time and within budget without systematic planing, project justification, budgets etc.

As an example of project management and proposing, which make up 50%-90% of a scientist's time,  I'm going to offer, as an experiment two extra credit  projects. I will now relate these to you in some detail. The first project a something you might all appreciate if it is done but it is not a "science" project. The second one is maybe impossible to actually carry out, but we'll see. However first project is **not** astrophysics based at all, and if nobody proposes that's okay. We'll have at least learned a little about project management and planning by my description of the process.

Extra-credit-credit project number 1:

Bake a very special cake. This cake takes about 6 hours to prepare after you have acquired the ingredient and the utensils and have found a place to bake it. The idea is for first you must assemble a team with a Principal Investigator =  person who provides overall direction and decision making and could actually do most of the baking in this case. Second, is project manager, whose job it is to facilitate the project and to make sure it is carried out on schedule and within budget. The project manager would find the kitchen, identify a source of the utensils, arrange for the acquisition of the utensils and the materials (at the right time), and would schedule organizational meetings; team members who might be experts in cooking and peeling chestnuts or experts in making butter cream sauce or over 21 so they can by the necessary rum or.... So the first task is to put together a team, which the PI does, and then the team must write a proposal that describes the facilities available, the skills of the personnel, the responsibilities of the personnel, and a detailed budget and a plan that describes how and when you will purchase the necessary ingredients. One ingredient that you might have to wait to acquire is chestnuts. They will not be carried in local stores until mid-Nov. Forget canned chestnuts, I used those once, and they are bad. After you submit the proposal I will judge the proposals. If there is more than one that is good I'll accept them and fund them. If your proposal is no good, you get no credit at all. IF you do a poor job on the cake, i.e. it doesn't look and or doesn't taste okay, then you get minimal credit (to be determined). You must also provide a detailed written report, and pictures or a video that records the entire process. If your cake passes, then you get the 20% of the total points allowable in the class added to you total.  Each team can consist of no more that 4 people, and I'll at most accept two teams. So first you have to judge can you put together a good team? And is this worth the trouble just to propose? Your proposal can be no more than 4 pages long, single spaced, 12pt, and 1 inch margins all the way around. It is due in class Oct 11. The recipe is given here (or ask me for hard copy): Chestnut Chocolate Torte

Delivered Products, see the images below!

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Extra-credit-credit project number 2:

The second project is to design a write a proposal to NASA for a micro-gravity experiment that can be carried out in NASA's "Vomit Comet." Your first task will be to find out all the details via the NASA Web page The Vomit Comet - project description is the place to start, but so far only the fall competition section provides details you need.  IF the proposal is deemed good, we can actually submit it, but first things first. The problem is that your system is only weightless for about 25 seconds at a time, so you have to think of something interesting that can be tested in an airplane in series of maneuvers that last about 25 seconds and can occur every few minutes. Note, you can't test animal or humans and you have to be prepared to go through physical training etc. I have not yet been able to think of some interesting process or test for 25 seconds that is significantly affected by being in micro-gravity. One that you might think about is the old Pepsi/Coke test: This was to design a container that allowed the astronauts to drink Pepsi (or Coke) in Space. Neither container worked. The problem is that without the gravity the bubbles did something weird: so the Pepsi container ended up ejecting baseball to grapefruit sized ball of froth, that the astronauts had great fun playing with, but not drinking. This project comes with the same credit as the other extra credit. Your proprosal which will demosntrate  that you are serious about writing a full blown proposal is due Oct 11 in class. Note, Prof. S. Lichter, who is in the Mechanical Engineering Dept here at NU, has flown on the Vomit Comet and may be able to give you prointers for proposal.

How about collisions? First a mini-review of Armageddon (I didn't see  Deep Impact). I have never seen a picture of an asteroid that is covered with stalagmites and canyons etc., and the asteroid is not likely to have 10's of 100 meter class rocks in "formation.'' (Comets, which are mostly imade of ice, are another story). Then there was the precise splitting of the asteroid into two neat pieces (I think not) and the implication that the space shuttle can orbit the Moon (NOT). Never mind, let's listen (read) to the following description of an impact that took place in the desert several years ago and look at the probabilities to consider how  much effort we should put into an asteroid "watch" (and destroy) program. Then we will move on to the basics of the  course and then some other course material.

"The Day the Sands Caught Fire" by Jeffrey C. Wynn and Eugene M. Shoemaker Scientific American, November 1998.

Imagine, for a moment, that you are standing in the deep desert, looking northwest in the evening twilight.  The landscape is absolutely desolate: vast, shifting dunes of grayish sand stretch uninterrupted in all directions. Not a rock is to be seen, and the nearest other human being is 250 kilometers away. Although the sun has set, the air is still rather warm-50 degrees Celsius-and the remnant of the afternoon sandstorm is still stinging your back. The prevailing wind is blowing from the south, as it always does in the early spring. Suddenly, your attention is caught by a bright light above the darkening horizon. First a spark, it quickly brightens and splits into at least four individual streaks. Within a few seconds it has become a searing flash. Your clothes burst into flames. The bright objects flit silently over you head, followed a moment later by a deafening crack. The ground heaves, and a blast wave flings you forward half the length of a football field. Behind you, sheets of incandescent fire erupt into the evening sky and white boulders come flying through the air. Some crash into the surrounding sand; others are engulfed by fire. Glowing fluid has coated the white boulders with a splatter that first looks like white paint but then turns progressively yellow, orange, red and finally black as it solidifies-all within the few seconds it takes the rocks to hit the ground. Some pieces of the white rock are fully coated by this black stuff; they metamorphose into a frothy, glassy material so light that it could float on water, if there were any water around. A fiery mushroom cloud drifts over you now, carried by the southerly breeze, blazing rainbow colors magnificently. As solid rocks become froth and reddish-black molten glass rains down, you too become part of the spectacle-and not in a happy way.