Why take astronomy and other general science courses? Usually answers to this question are something vague involving words such as "requirement", "well rounded education" and "critical thinking skills". Well, why is it a requirement? How is astronomy going to help you on your way of becoming a polymath (look it up)? And just what the !@#$ are "critical thinking skills"? Let's not worry about the requirement - that has to do with school policy and yes you can make it through life without knowing anything about the moon Enceladus and still have a well-rounded education. But I can answer the last question: Critical thinking skills can be loosely defined as observing some phenomena and drawing a conclusion based on sound reasoning. It is my dream/desire/hope to get you all aware of this process- it is a powerful tool applicable to all fields. In fact if you've ever written a paper analyzing something whether its a piece of art, literature, a historical event or investigative journalism you've used critical thinking skills. Astronomy is a good vehicle for demonstrating this because unlike other fields in science, the data are limited to observations of large objects we can't manipulate. We are stuck with our Earth/Solar system bound perspective. Math is the language that describes the observations and gives us power to predict the position, for instance, of an asteroid or determine whether some distant planet is similar to Earth. Our society is becoming more and more "app-based". Instead of figuring something out by thinking through the data, we tend to look up answers on our phones, laptops and have no understanding of how the answer was determined in the first place. More often than not, it doesn't occur to us to ask how this answer came about (unless its required for homework). Why is this bad? Our brains get flabby. We don't know how to solve more complex problems like reducing our dependence on diminishing world resources, fixing an unsustainable economy or worse yet, figure out which direction is east without our phone/gps because we forgot to charge it. Tsk Tsk.
Have you ever wondered how we know that the mass of the sun is 2 x 1030 kilograms (that's a 2 with 30 zeroes after it)? Its not like we can go out and weigh it. There must be some physical law (there indeed is) that must help us calculate it. What is this law? Ans: Kepler's 3rd law and Newton's laws of Gravitation. How did these ideas/laws come about? Ans: Many, many, many observations that all seem to fit a consistent pattern and can be expressed in a mathematical equation. How can we trust it? There are so many theories that come out online from highly uneducated, unqualified people that claim they have a theory for everything and Newton/Einstein/"insert prominent scientist here" was wrong in their explanations and formulas. Ans: Well the beauty of a physics law (fyi: astronomy is based on physics) is that it is well tested for many different circumstances and has the power to accurately predict phenomena consistently. All theories/laws must fit observation, otherwise it's crap. The crazy theories don't pass the consistency check and usually involve something very unphysical that violates a whole lotta other physics laws that are also well tested. When a law works well but not for all regimes (Newton's laws do not predict Mercury's orbit accurately due to its proximity to the sun- which is something we will discuss in class), it means we need to improve the old law and rethink what we knew and improve the predictability of the law. Physical laws are not some "absolute truth" descended from the ancients. They are simply very, very good approximations of phenomena, having consistency from observation to observation and assist us in exploring the nature of the Universe.
This is never stated enough, but the real way to learn something new is to accept that struggle and failure are a part of the process. Seriously. We do this so much in physics whether it's calculations or taking data or programming that you know your first 10 or more trials are going to suck....And then you keep doing it until you get it right. That's how real life works. Our society focuses too much on the end product of awesome skills and forgets there was a struggle to get there. So don't give up!
I really want you to get something positive from these astronomy courses whether you decide to study philosophy, gain confidence in your math skills, decide a career in science or just a general appreciation and new perspective of our place in the Universe. I welcome constructive (stressing constructive here not malicious) feedback to make this class a fantastic experience. Be an active participant in your education!