Astronomy

The National Science Foundation polled 2,200 random Americans in 2012 and found that 26% of those polled believed the sun revolved around the earth. It didn’t seem like a trick question. They asked, “Does the Earth go around the Sun or does the Sun go around the Earth.” Our collective failure to do better as Americans alarms me. The American Association for the Advancement of Science was talking about that poll at their annual meeting not long ago in Chicago. Sounds like they have their work cut out for them, advancing science that is, especially when it comes to astronomy.

Not that we’re doing that bad compared to the rest of the world. The European Union asked the same question in 2005 and 33% of their polling sample answered it incorrectly. So we have no corner on the “stupid when it comes to the solar system” market. I can’t believe the Europeans would have gotten a whole lot smarter than us in the past nine years. Really do you find yourself talking about or reading anything to speak of about planets and all these days? I don’t. Most of what I learned about astronomy I learned a long time ago. So I guess even more European grade school kids than Americans missed that movie in Science class where a model of the Sun was sitting, big as life and not moving an inch, in the middle of the screen while Mercury raced around and around it, the Earth sort of jogged, and Neptune seemed to hardly move at all. If you saw that movie and remembered any part of it could you have forgotten the Earth went around the sun? Apparently so.

What we do talk about, almost incessantly, is the weather. You can hardly get away from weather talk. Especially now. Especially this winter. We talk about weather forecasts, wind chill calculations, snowfall records, and last but not least the newly discovered polar vortex. It’s getting a little old actually, all this weather chat. I’m ready to move on.

Actually, astronomy has a lot to do with weather, although we don’t often link the two. In addition to distance from the sun and orbital path there are three basic things that determine weather on a given planet; length of time to orbit the sun (year), how often a planet spins completely around (day), and how much it wobbles (axial tilt). Orbit, spin, and wobble.

Mercury, which goes around the sun once every 88 days (Earth days that is, all these days I’m talking about are Earth days) has an 88 day year, but surprisingly it only spins around completely only every 60 Earth days, which means a day on Mercury lasts damn near two thirds of a year. And there is no axial tilt on Mercury. 0 degrees. No wobble at all. That means you’re always the same distance from the sun no matter what time of the year. There would be no seasons as we know it on Mercury. Everybody agrees, I think, that it would be way hot on Mercury. The only saving grace could be some very long nights, thirty day conceivably, matched with equally killer long days. I imagine it would take quite a while for Earthlings to get used to life on Mercury. That weather there could mess up your biorhythms in a big way, to say nothing of the risk of skin cancer. Imagine the SPF numbers.

Venus would get you closer to normal in terms of its length of year at 224 days, but a day on Venus, believe it or not, lasts longer than its year. A day on Venus, the amount of time it takes for the planet to spin completely around, is equal to 243 Earth days. Talk about your adjustments. Sunsets, I figure, would last weeks. Maybe that’s why Venus is considered so romantic; long sunsets followed by even longer nights. And Saturday, if they wanted it to, could last 35 days or so. I’m guessing if life on Venus resembled ours even at all they would have worked out a completely different schedule by now. Axial tilt on Venus? The thing that decides it’s seasons? Confusing. It is either 177.4 or 2.6 degrees, depending on your definition of the "north pole." I can’t figure that out. Even though I like to dabble in other fields from time to time I am, after all, an English major. Maybe someone else can tell us what that’s all about.

Mars, on the other hand, has the sort of set up your can get your head around. It spins completely around every 24.3 hours, just about like us, and has a 25.2 degree tilt to it, which would give it more or less our schedule of seasons. The Earth’s tilt is 23.5 degrees. The only kicker about Mars is that it’s year is 687 days. So the seasons, as similar as they might be, would last a lot longer than ours, like about five months rather than our three. You could go to Mars and all things being equal get with the celestial program fairly quickly. Plus the Cubs would have a much longer spring in order to train for the season. Maybe the Ricketts family should consider Mars if the city and the fans don’t cozy up to their demands for Wrigley field.

I hesitate to talk about the other four planets; Jupiter, Saturn, Uranus and Neptune. They’re just out there. Their days have reasonable lengths, the amount of time it takes for the planet to spin completely around, in fact all are shorter than the Earth’s. But the farther out you go, the longer their years get. A year on Jupiter is 4,331 days while a year on Neptune is 60,190 days. You think this winter is long here on Earth, think of getting through winter on Neptune. You could be 41 years old before you saw your first crocus bloom. All of them have seasons, though very slow developing, except for Uranus which has an axial tilt of 98 degrees and spins like a ball rolling down a sidewalk rather than a top. I can’t even start to figure out what that would do to your weather map on the evening news.

Be that as it may, that’s ends my lesson on planets going around our sun. Maybe we’ll do better on the next survey. And I remind you again that all the time the planets are spinning and orbiting and tilting this way and that the sun is just sitting there, shining away, being a star. That’s how it works here in our solar system.

And while I have you here, I want to point out that all of us here on Earth are 59 days into our calendar year, and 69 days past the winter solstice, that day when we in the Northern hemisphere were tilted, because of our axial wobble, farthest from the sun, experienced our shortest day, and received the least amount of sunshine. On that day, December 21st 2013, the sun rose on the shack at 7:16 in the morning and set at 4:20 for only 9 hours and 16 minutes of sunshine. Let me correct that. The sun just appeared to rise. That’s just the way we say it. Actually the earth turned the place where you live toward the sun, which stayed in one place as the Earth spun and moved around it. Today, seventy days since the winter solstice, “sunrise” was at 6:27 and “sunset” at 5:38. That’s 12 hours and 5 minutes of sunshine. We received two minutes more sunshine than the day before. March 1 gets us four more minutes. It’s happening folks.

Each day we get more sunshine and the angle of the sun makes the sunshine stronger and hotter. You can feel it. That snow you see today will be gone soon, I guarantee. The ground will thaw. Grass in your yard will turn green faster than you can imagine. You might see green on St. Patrick’s Day, 17 days from now. Four days later, on March 21st, day will equal night and by June 21st, 113 days from today, you’ll be sitting on your patio, perhaps having a beer, considering what you’re going to do on the 4th of July, and complaining about the heat. On that day we will have 15 hours and 27 minutes of sunshine. It will be summer. You will have forgotten, by and large, what it feels like to be cold. It happens every year. You can count on it, all because the Earth travels around the sun and tilts on its axis.

The sun has winter on the run. Start planning your garden. We’ll be planting potatoes on Good Friday.