Learn something new every day.
And have fun doing it.
Look up. How many stars do you see? If you had unobstructed vision around the earth in all directions, and if we didn’t have an atmosphere to cloud up the view, you’d see, in theory, at least about 200 billion trillion stars. If I don’t miss any zeroes, that’s 200,000,000,000,000,000,000,000. That’s almost as much as our politicians could spend in a year if they put their minds to it. And that doesn’t begin to count planets. In our solar system, we have eight, or maybe nine, depending on the current membership status of Pluto, but who knows how many planets all those stars have circling them like starving paparazzi? And don’t get me started on moons. The net-net is there is a whole bunch of stuff in the universe.
If you want to break your brain, consider that more than a few astrophysicists believe that at the moment before the Big Bang, all the matter in the known universe, those 20 sextillion stars and all of their associated groupies, were compressed into a space one-trillionth the size of the period at the end of this sentence. Sorry, not sorry for plunging your gray matter into the abyss of “mind blown” for the day.
Infinity in motion
The cool thing to see is all the motion of our little slice of that vast universe. If you put down the smartphone, go outside, and chill out for a couple of hours while looking to the heavens, you’ll see all those stars and constellations we’ve named moving around the sky. It’s fascinating.
Actually, what we see isn’t the universe moving but the earth spinning. Sure, the universe IS expanding. Back in the 1920s, Edwin Hubble (yeah, the guy the telescope is named after) figured out the universe is expanding, and the outermost reaches of the universe are expanding at a faster rate than the inner billions of trillions of stars. His work inspired the Hubble Constant, which, when multiplied by a galaxy’s distance, can begin to describe these relative velocities. Some smart folks, but not all, believe the math works out to somewhere around 70 km per second per Megaparsec distance.
In case you’re wondering, a Megaparsec is about 3.26 million light years. That’s a long way, far beyond the range of today’s most exotic electric cars. To put the distance in perspective, Proxima Centauri b, the closest star with planets, is about 4.24 light years from here.
Our spinning top
But back to more comprehensible things and how you can use some of this mind-bending information.
All those stars appear to move in the sky because we spin around our polar axis like a top. So, if you left your camera on all night pointed up, you’d see a circular pattern of star movement.
If you’re reading this from the Galápagos Islands, you’re zipping along right now at about 1,037 miles per hour thanks to the earth’s rotation. Of course, if you live closer to one of the poles, you’re moving much slower, say about 500 mph in Anchorage, Alaska. And if you’re standing on Santa’s barber pole, you’re not moving at all but perhaps getting dizzy from spinning in place. OK, the spinning sensation part isn’t true, but you have to admit it makes for a great visual.
North Star tips and tricks
All of this spacey stuff does have some practical application.
I always get a kick out of finding the North Star. Serious astronomers call it Polaris, perhaps because it is positioned over the North Pole and not subject to moving around the sky like all the other stars. That makes it a wonderful navigation aid, at least at night, provided you can find it. Assuming you’re in the northern hemisphere and it’s a clear night, you can get a pretty decent fix on which direction is up, so to speak.
The Big Dipper points the way
Finding Polaris (the North Star) is easy if you’ve ever spotted the Big Dipper. Didn’t we all do that as kids?
Just look for the “dipper” part, not the handle, and follow the two stars that define the side of the cup away from the handle, and they point right to Polaris.
It’s a fun tool to file away and share when enjoying the outdoors at night. Who knows? That knowledge might save your life or, at minimum, help you get your bearings when in a new place.
North Star … For Now
Now for the bad news. If you live to the ripe old age of 15,000 or so, you won’t be able to use the North Star for navigation anymore. Remember the spinning top thing? Earth wobbles like a toy top but far more slowly. Thanks to this precession (the scientific term for wobbling), the star Vega will be the new North Star. No worries, though; by 27,000 AD or so, Polaris will be back in charge and leading the way north again.