ASTRONOMY 1040

Class Notes #1

• What is the "scale" of the Universe. In other words, how big are various things compared to each other, and how far apart are they? We will hit upon this during the course, but here is a website that give you some sense of scale for the sizes of things, although NOT of the distances between them:
  SCALE (Remember, this does NOT show the relative distances between planets or stars and planets. Ask if you have questions)
• How long for each moon phase and how are they observed in different parts of the world
• When do the various phases rise and set?
• What are the relationships between the phases of the Moon and the location of the Sun
• When can solar and lunar eclipses occur? What lunar phases for what types of eclipse
• What are the geometries of both kinds of eclipses?
• How long do eclipses last, and how often do they occur?
• Why don't we have eclipses every month?
• Where do the planets appear in the sky?
• What is the Ecliptic, the Celestial Poles and the Celestial Equator?
• What are the coordinate systems that astronomers use?
• What is altitude and azimuth?
• What is a geocentric and heliocentric viewpoint?
• What causes the seasons? How does the position of the Sun in the sky change during the seasons?
• How does your position on Earth affect the season you have?
• Why is it cold in winter and warm in summer? When we have winter, what season is it in Australia?

Be sure that you have read the syllabus, schedule and policies for this class. Although I have tried to answer most basic questions on this website, I cannot anticipate all of your questions. You must ASK! (Unless you have a question that is personal or sensitive in nature, use the Message Forum or for lecture-class students, ask in class.)

Furthermore, you MUST stay in touch. If you have computer difficulties or email problems, get them fixed. There are simply too many opportunities to get online for anyone to use computer problems as an excuse. If your computer or Internet connection go down, use a friend or relative's. Or use a computer on campus or a public library. Of course there are also Internet cafes and businesses like Kinkos where you can access the Internet for a fee. The point is that you have access to the Internet even if your personal computer goes down.

Also, please use your own Metro email address. Do not email to me from another student's email address (except for temporary circumstances). It is very confusing for me for two students to be using the same email address. The roster lists I use to send you email only have the Metro address for you, and in those cases I cannot change it to another address. Therefore, if you do not use your Metro address, you may not get all my emails.

And never, ever send email attachments unless you get my OK first.

Your textbook is The Essential Cosmic Perspective, Third Edition, by Bennett and others. Be sure that it has the word "Essential" in the title. Otherwise it is the full Third Edition, and perhaps a bit more than you want to deal with. You can still use it, because it has all the same material, but there are chapter and page number differences and a lot more material than our official course edition.

Introduction

This is a survey introduction to ASTRONOMY, not ASTROLOGY.  Astronomy is the scientific study of the heavens. Astrology is fortune-telling. Both deal with stars, but there is a big difference between the two. Please get the distinction down and never refer to this course as astrology. If you do, I will take it as an insult.

Astronomy is the aspect of Physics that studies the nature of the outer Universe, whereas most of the rest of Physics looks inward to the atomic and subatomic realm, as well as to the greater and more basic questions of the existence of the physical world.

Although you will have a chance to visit Chamberlin Observatory or other observing sites, we do not concentrate on learning the constellations, or observing through a telescope. We learn a little about the history of astronomy, the tools and physics of astronomy, and the subjects of astronomy -- specifically the stars, planets and associated bodies. In addition, we will dip into a specialization of astronomy and physics called "cosmology" to consider the origin, evolution and nature of the physical Universe.

How this class works

I give this class in two forms: on-campus lectures and online classes. This site is specifically for online students, but lecture class students get their activities here, and can find much useful material here as well. However, lecture class students cannot access the tests online. The requirements for the online sections and the on-campus (lecture) sections are the same, except that online students take their tests and turn in their activities through the Internet, and do not attend lectures. Lecture students take their tests and turn in their activities in class. 

You are responsible both for the textbook readings as outlined in the schedule, as well as these notes.

You will have several tests and several activities (homework) to complete. The tests and activities have strict deadlines and time limits. If you exceed the deadlines or time limits, you will get a zero. Period. Online students no longer have to come onto campus to take the final.

Since probably all you have come into the class with different background and preparation, some of you may think it is too hard, while others may think it is too easy. The important thing is to let me know if you are having problems. I may or may not be able to help, but in any event you have to let me know. Otherwise I definitely can't do anything about it.

You MUST pick a regular time for study. It can be any time you like, and for any length you choose as long as it is frequent enough and long enough to get your studying and work done. But let me tell you, whatever time period you pick, something will always come up. Don't let it take you away from your studying. Be conscientious about this and treat your study time as if it were a regular classroom period in which you would be graded on attendance.

It is easy to fall behind just by saying, "Oh, I'll get caught up on this Thursday night or next week." If you think like that, you WILL fall behind.

OK, that said, let me also say that this course can be about as hard or as easy as you make it. If you want a good grade, I suggest that you make it easy on yourself. Here's how:

1) Set your study time and stick to it.

2) Read and study each assignment

3) Do each project, activity or quiz by the deadline

4) Prepare your questions and submit them to me when you think of them (not later)

If you give yourself an adequate amount of time and follow these instructions, you should do well. You don't need to be an "rocket scientist" to understand this material, but you have to at least make the effort to understand and keep up. Getting questions answered early is far more useful than holding them (and possibly forgetting them) to send in all at once.

And one more thing: Don't blow off the Activities! This is one area where students tend to get themselves into trouble. The activities have deadlines and they count a large portion of your semester grade. No matter how well you do with the tests, if you do not do the activities, the best you can possibly hope for in this class is a D. So start them in time and turn them in on time. I tend to grade generously on activities, but a 0 is a 0 no matter how you look at it. Every single semester I have a few students who do very well on tests, but don't even bother with the activities. Of course they fail the course or at best get a "D."

Necessary Skills

In order to succeed in this class and the rest of life, you need certain basic skills. Most students already know and use these skills on a daily basis. However, some students, when confronted with their necessity in this class freeze up and panic because they think don't have them. Relax. All students have the capacity for this. You may have to refresh your memory or -- heaven forbid! -- learn a little something new, but you can most assuredly do it. Here are some necessary skills for this class:

Confidence -- Of course this is really an attitude rather than a skill per se. This is not a problem for most students, but if you lack confidence in your abilities, there is no need to worry. I have taught these classes for many years, and I can assure you that if  you have gotten this far in your education, you can deal with this course. Just don't let worry and procrastination get in your way. Just do it!

Critical Thinking -- Critical thinking is a life-long process and not one that you can pick up in a few days for a class. Critical thinking is the process of looking at things and constantly asking yourself, "Is this the best way to do this?" or "Does this make sense?" or "How can I check to be sure this is true?" Critical thinking is not being negative, but rather just questioning things to be sure you are on the right track. It will help you avoid problems in this class and life in general. Critical thinking is logic applied to life. In Demon Haunted Life, the late Carl Sagan provided a Baloney Detection Kit, which is helpful in developing critical thinking.

Math -- Math is a stumbling block for some students. However, the math necessary for this course is not at all difficult. We don't do trig or calculus, just basic addition, subtraction, multiplication and division. We do often combine two or more of those into what some students will recognize as introductory algebra, but is certainly not beyond your ability. Combined with the Metric System and Scientific Notation, a simple observation done in your backyard can yield the circumference of the Earth or the diameter of the Sun. You will be amazed! I've written a short file on what you need to know about Math. Please read it and let me know (use the Message Forum) if you have questions. Or if you need more, here is Math Help.

(By the way, I make a big deal about math because so many students fret so much about it. Don't let that give you the wrong impression. There isn't that much, and any that you do encounter is well within the capabilities of any college student. In fact, aside from seeing some really big numbers in the textbook, just about the only place you will encounter any math is in the activities. Any references to math on tests will be few and extremely basic.)

Metric System -- The Metric System just makes a lot of sense and knowing something about it is very useful outside of this class. But nothing at least a little about it is essential for this class. The truth is, you really don't have to know much. We really only deal with mass and length, basically grams and meters, and variations on those (such as kilograms and kilometers). The basics of what you need to know are here: Metric System Basics.

Scientific Notation (Powers of 10 or exponents) -- As with everything else here, you have encountered this somewhere in your education. It is a way of expressing big (and small) numbers, and actually simplifies calculations. Fortunately, you don't really need it for computations, but you do need to know the difference between say, 10 and 10², or the difference between 2 X 10³ and 2 X 10⁹. Those little numbers (exponents) make a big difference and cannot be ignored. By ignoring them, students in the past have made enormous errors, in effect implying some ridiculous things as the Earth is the size of a watermelon. You don't want to make such mistakes, so before we go further in Astronomy, take a little time to learn just a smidgen about Scientific Notation. Here's a little more help: Scientific Notation Basics.

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