Earthbound

"He has no place to go, no home but the earth."

Thus concludes Charles F. Park, Jr. in his 1975 book Earthbound: Minerals, Energy, and Man's Future. I'm a big fan of space exploration, manned spaceflight, and science fiction stories, but it is unlikely anyone I will ever know will live on another planet. Visit, sure. But live? Be part of an alien ecosystem? No. That's not going to happen soon. We are stuck here on the earth and have to make the best of it. The Andromedans or Cassiopeians or Alpha Centaurians are not going to suddenly appear and give us free, limitless, non-polluting energy. We'll still have to farm our food and we'll still need all the other stuff we currently grow. And, like always, we'll  have to mine the rest. I'm interested in things and how they get put together. Where does the lead for my car battery actually come from? How is it transported and processed? What does it take to turn rocks into something like a toaster or a hammer? Earthbound may have been dated, but it piqued my abiding interest in economic geology. I suppose growing up surrounded by things like seaports and oil refineries got me thinking along those lines. I wonder about the connections necessary to put an iPad in someone's hand, the actions and events along the way, the myriad of both social and physical structures required. No matter what, when you follow the chain to the end, there's always some guy digging a hole in the ground and pulling out some useful chunk of the earth. I want to know more about that guy, that hole, and the treasures buried there.

Conjunction!

Not much of a photo, I'm afraid, but the conjunction last night between Jupiter and the gibbous moon was pretty neat:

According to my Abrams Planetarium Sky Calendar the two celestial objects were 1.3º apart.

Breaking In Breaking Bad

Chemistry teacher is my day job. Thus, I have endured a continuous stream of inquiries from all my friends, family, and acquaintances about my thoughts on Breaking Bad, the AMC show that's garnered a lot of attention and praise. I'm always tardy on whatever is hip, be it music, movies, or TV shows, and sometimes entire decades (like the 90s) are a complete loss. But we picked up a blu-ray copy of Breaking Bad Season One this week and popped it in the player one night. And watched the first four episodes straight through! And we watched the final three the next night. This show, like the methamphetamines the main character cooks up, is highly addictive. The two principals (Bryan Cranston as Mr. White and Aaron Paul as Jesse Pinkman) are brilliant and have an excellent chemistry (very punny, eh?) on screen. The story is a classic one, a good man having to "break bad" in order to stay afloat in a sea of troubles, but is updated for modern times with Mexican gang-bangers, chemotherapy, support groups, high-tech entrepreneurs, overzealous drug cops, and hip-hop lingo. Dark, funny, clever, stylish, pacy, and nervy, Breaking Bad is as good as it gets on TV. If you aren't already snortin' crystal (figuratively, of course), you need to get on the ice-wagon, put your face to the glass, do your biz with the rizz, and adelante with the scanté by tuning in for Season Five. I'll be a couple of episodes behind you, of course.

Closest Approach

This week the Earth comes closest to the Sun on its annual journey along the elliptical path. The distance between the two bodies drops to a mere 91.4 million miles or about 147 million kilometers. Around Independence Day the Earth will be at its furthest point: 94.5 million miles or about 152 million kilometers. Stick two pins in a piece of cardboard and tie a loop of string between them. Using a pencil, trace out a shape by stretching the string all the way out. What you get is an ellipse:

The two pins represent points called the foci (plural of focus). If the two foci were one point, your ellipse would be a circle. Imagine the Sun is one focus. The Earth's orbit is the ellipse. When the Earth is furthest from the Sun, it is called aphelion. When it is closest, it is called perihelion. "Helios" is Greek for "sun" and "ap-" and "peri-" mean "far" and "close." You can see that the ellipse illustrated is highly exaggerated. The Earth-Sun distance only varies by about three million miles, so if we could view the orbit from space it would look very much like a circle. Most people have a hard time with the notion that we residents of the Northern Hemisphere are closer to the Sun in winter and further in summer. It is below freezing where I live today, for example, and will likely be in the high 80s or low 90s (Fahrenheit) on the Fourth of July. We should conclude, then, that the distance from the Earth to the Sun is not important when talking about the seasons. Three million miles may seem like a lot, but not when you are 90+ million miles away! Every schoolkid ought to know that is is the axial tilt of the Earth that gives us seasons. If you have ever spent time in the Tropics, you know that the day length varies little throughout the year. Whereas we folks who live in the Temperate Zones experience long summer days (and short nights) and short winter days (and long nights). The Earth's axis tilts 23.5º from the plane of its orbit, which is why the Tropic of Cancer is 23.5º north of the Equator and the Tropic of Capricorn 23.5º south. This axial tilt means that solar radiation is spread out over a larger area during the Northern winter and thus we get colder weather:

Try this with a globe and flashlight. You'll see the beam will cover more ground when the Northern Hemisphere is tilted away (winter) and be more concentrated when tilted toward the light source (summer). This is a simple concept, and it gives us an easy scheme for describing seasonal change. After you get a handle on it, ask your friends what they know. You might be surprised how many of them have no grasp of grade school science. Be a good citizen and enlighten them.

HAPPY PERIHELION!!