It's Bigger On The Outside

In light of my previous post regarding my visit to Cherry Springs and stargazing, I'm gonna go into the details of one of the favorite aspects of space: It's Big. Keep it at that and we might have a strong contender for Understatement of the Year. Sure, that only scratches the surface. The things we know about space can be compared to the things we know about the deep ocean - very little. A lot of general statements, a lot of loose estimations. Distances and names are the building blocks. Data on the materials composing other planets in our solar system alone are still being discovered. 

Hmm... Okay, let's start close and work our way out.

Observe, if you will, with your mind's eye, our immediate planetary space, atmosphere, and gravitational pull. Our planet has one natural satellite and 2,271 manmade ones. This specific definition of satellite here excludes any chunks of burnt up meteor or debris from space missions. So that's currently one moon, 2,271 human contraptions zipping across our sky. The International Space Station, for example, orbits the earth about every 90 minutes, giving it approximately sixteen orbits in one 24-hr period and you can call it a day hahaha. 

Zoom out a bit, and we have the Inner Planets. There's the asteroid belt that divides the inner and outer planets of our Solar System. In a tight huddle around Sol, our only star in our system, we have Mercury, Venus, Earth, and Mars, going outward. Of the Inner Planets, Earth is the biggest (radius of 3,959 miles), Venus is the hottest (462 degrees Celsius), Mercury is the smallest (radius of 1,516 miles), and Mars is the reddest (got some rusty dust there buddy). Back out further, and we have eight planets, since we add Jupiter, Saturn, Uranus, and Neptune to the mix. But where's Pluto?, the ancient voices cry in dismay. Don't worry, I think Pluto got an upgrade rather than a downgrade. Sure, it's not a planet, but it is one of many Dwarf Planets. Actually, Pluto is the biggest Dwarf Planet (radius of 737.6 miles)! And it lords over its own subcategory in a subcategory in a subcategory in a subcategory of heavenly bodies!

Uh... Let's break that down. Pluto is a plutoid (an ice dwarf planet) which are unique Trans-Neptunian Objects (dwarf planets that orbit past Neptune) that are a subset of Minor Planets (asteroids, centaurs, trojans - the very small of the large things) which all fall under the umbrella term of Dwarf Planets (anything too small to be a planet but too big to ignore should it come careening towards the earth bent on total destruction okay I'm kidding but only a little).

Think Pluto still got the raw end of the deal? Maybe Pluto should leave Sol's orbit for another sun, then? Well, the nearest neighboring star, Alpha Centauri A, is 4.367 lightyears away. For some perspctive, Sol is 93 million miles from Earth. Alpha Centauri A is part of a star binary with its pal, Alpha Centauri B, and an honorary mention to the red dwarf star Proxima Centauri that is not close enough to be involved in the binary tango to become a tertiary, but appears to be gravitationally bound to the other two. That's three stars for the price of ditching our one yellow star! Quite the bargain, Pluto. It's a shame Dwarf Planets don't really take vacations.

Now we jump out yet again... Ah, that was quite the jump. There's the Milky Way Galaxy. It's about 1,000,000,000,000,000,000 kilometers across, or 100,000 lightyears if that helps. That's our galaxy. We can see it slash across the night sky in a cloudy streak of light, if there's not too much visual noise getting in the way. So many stars, so many planets, and we're just on one of the outside spiraling arms of it - the Orion arm, to be exact. That's not even one of the big-time arms either. It's secondary and between two other larger arms. So, whenever someone asks if we're at the center of the universe, well, haha, we're not even at the center of our own galaxy, one of approximately one hundred BILLION galaxies. Probably. There's most likely more. We just don't know. 

Our closest neighboring galaxy is Andromeda, a mere stone's throw away at 2.5 million lightyears. A reasonable day trip, if the day is 2.5 million years long and we can travel at the speed of light. At the speed we can travel in space right now, we'll get there in about 785,200,000,000,000 years, so just in time for lunch!

It's a big accomplishment for us as a species to know as much as we do now about the moon, our own natural satellite. And yet, there's so much more space to go. I backed out to the next closest galaxy, but that in reality is only barely scratching the surface. Our tiny minds simply cannot fathom the true capacity and sheer vastness of space. It is too gosh dang big. Makes me think of the original definition of 'awesome' - to be struck by awe. Filled with wonder... and with terror. We have so much to learn. I'm glad I got to glimpse some of it.