Sunday, April 8, 2012
VISUALIZING THE UNIVERSE:
By Abbi Allan
Close your eyes.
We are starting here at home, on Earth. To take this trip into the universe, we are going to have to travel extremely fast. Even if we were traveling the speed of light, 186,281 miles per second, turning ourselves into energy, it would still take us far more time than we have. It would be billions of lifetimes over.
Sure, it would be fast locally. We could go from New York to London in a tenth of a second. It would only take us less than a second and a half to get to the moon, and only 8 minutes, 30 seconds to make it to the sun. It’s fast relative to our solar system, but even at the speed of light, it would take us 4 years and 2 months to reach the closest star within our own galaxy! And that’s just on the same block! We are going to go far further than that.
People are just one of billions of different life forms on earth. Our rich diversity comes from all the different solutions to all the different environmental conditions we have on Earth. Deep-sea vents where the animals live off sulfur, parasites in an acidic stomach, bacteria in the artic, and birds in paradise. There isn’t a place on earth that doesn’t house some sort of life. Think of all the different plants and animals that have long come and gone, now extinct. Most of them looked like they came from another planet! I’m sure the dinosaur would say the same thing about us if they could.
Now we are going to leave Earth.
Our planet is just one of nine, (and now possibly ten or more) orbiting our only star, the sun, within our solar system. Our Sun is barely notable. It may be special to us, but is only one of a billion stars within our galaxy, the Milky Way. Think of all the possible planets there might be surrounding those stars? Think of all the variety we see within our own solar system? Just about anything you could possibly imagine might possibly exist. Imagine each star as a house on your block. That would be A LOT of houses!
Our galaxy is one of 30 or so other galaxies within our local group. It is like our celestial neighborhood. Lucky for us, we are one of the three largest of these galaxies, so a lot of the little ones orbit around us. This is because our mass is so great that we are actually denting the fabric of space, pulling the little ones in!
The Milky Way is beautiful. One of the few spiral galaxies other there. It looks like a swirly Frisbee. In the center are all the older stars, 6,000 light years thick worth of them. Their heavy mass helps pull the arms around them. These arms hold the birthplaces of our galaxy’s newest stars that shine brighter than those in the center. The Milky Way is a mere 100,000 light years across, and 2,000 light years deep.
We can look over and see another cluster of galaxies far away. It is the Virgo Cluster, 50 million light years away to be exact. If you lived to be 100, you would have to live five hundred thousand times to reach it! (And that’s at the speed of light!) This cluster holds over 2000 galaxies, and with all of those stars, it is just breathtaking. A treasure chest in the sky.
It doesn’t stop there. That Virgo cluster, and ourselves and surrounding neighborhoods all are part of a Super Cluster, holding a dozen or so more of these Clusters!. This is the largest structure in the universe that we know of. It looks like a big soap bubble, with all the clusters, groups, galaxies, stars, planets, and us, all on the surface, with big spaces of nothing in-between. What’s amazing, is our bubble, larger than 100 million light years across is one of many. They are all piled on top of each other like a tub full of soap bubbles, and we have no real idea how large our tub happens to be. And for that matter, if there are any other tubs outside of ours full of galactic bubbles! Even crazier, is our tub is growing larger and larger, faster and faster each second.
We just can’t push ourselves fast enough to catch up with the edge of this expanding universe. It looks like red sunset that never slips under the horizon, but recedes further and further away in the distance, so we’re just going to have to guess what’s beyond that. As we ride back to Earth we have to think about the most amazing part of all of this. Everything in this universe, our super cluster, cluster, local group, galaxy, star, solar system, planet, region on earth, neighborhood, block, house, room, you… even every single cell of you, it’s all made of the same stuff. The same 103 plus elements that all came to be at the instant right before time began. All of this was crammed into a point smaller than a pinprick, and heavier than anything we can think of. The moment this little pinpoint exploded, which we call the Big Bang, it allowed the opportunity for you to exist. We all made of stardust and this week, we’re going to find out just how that is.