Hollywood has a long and fruitful history of making disaster movies that feature large quantities of humans being wiped out by “off-planet” forces: asteroids, solar flares, aliens, and so forth. From Armageddon to Deep Impact to War of the Worlds to Independence Day, we eat this stuff up like candy.
So how many people in history have been killed by space matter or aliens?
None. (Well, there was a dog that was allegedly killed by a meteorite in Egypt in 1911. But the single eyewitness account was pretty sketchy, so the story is considered to be the Egyptian version of crop circles, or Bigfoot.)
How about people being killed by events originating from this volatile, molten planet we live on? Well, last year alone, the figure was over 250,000.
You’d think we would have examined this place a little more closely.
Humans have traveled over 200,000 miles from earth (to the moon). A man-made instrument, Voyager I, which we launched in 1977, is now an astonishing 10,829,000,000 miles from Earth (at its last report in February.)
So how far have we delved into the ground that we walk on each day?
I thought you’d never ask.
We all remember that the Mariana Trench, in the Pacific Ocean, is the deepest place on earth: 6.8 miles down. Sounds intriguing, right?
In 1960, two Navy sailors traveled to the bottom of the Mariana Trench in a submersible. They stayed there for 20 minutes, peering through a single, tapered Plexiglas window at the murky water outside, and then they kind of shrugged their shoulders and rose back to the surface.
No human has been back to the Trench in the fifty-one years since.
Ten years after the Mariana Trench expedition, Soviet scientists decided to see how far they could go into the earth. They drilled and drilled and drilled, and this is a good place in the story to go make yourself a sandwich, because they kept drilling and drilling until, thirteen years later, they reached a depth of 39,000 feet, at which point they stopped operations for a year to “celebrate” (which, one dearly hopes, translates to “drinking large quantities of vodka on a sunny beach in Fiji.”)
And then they got back to business, and drilled with admirable tenacity for another eight years, at which point the working temperature was 356 degrees and they realized that in another 9000 feet (give or take), it would get so hot that no drill bits on earth would function. So they stopped.
After nearly 22 years of drilling, they had reached a final depth of 7.6 miles, and that’s as far into our globe as mankind has ever gotten.
Here is a diagram of the earth. See that paper-thin outer layer, the crust? 7.6 miles – the farthest we’ve ever gone, remember – only gets you 1/3 of the way into that tiny layer.
In recent years, Hollywood has paid a little more attention to home-grown disasters, as in the movie 2012. I wonder how many people who saw that movie realized it was partly based on a real geological concern: the fact that Yellowstone National Park is perched on top of the largest “supervolcano” in North America, which is overdue for a “supereruption,” which is a lay-term (and I’m not making any of this up) that signifies an extinction-level event.
But I digress.
The fact is, with most natural disasters that come from the atmosphere, such as hurricanes or tornados, we have gained enough knowledge to build instruments that buy us at least a small window of warning. But when it comes to earthquakes (and their subsequent tsunamis), as we’ve seen so tragically in the last year, we are utterly helpless.
We’ve gone 10,829,000,000 miles into space, and a measly 7.6 miles into the ground. No wonder we are so caught off guard by the roilings and boilings of this planet.
Turns out, the Great Unknown is right underneath our feet.
Cathy LaGrow 
Okay, I hate to admit this about myself but I think I got into this one because I didn’t have to be Grant Huhn to understand it!! Ha!! (That was a compliment to you both!) Good read!
Thank you! This means I am going in the right direction! Whew…
Well, I say we just go celebrate TODAY, on a beach in Fiji, with a bottle of “wodka” (and oj because raw vodka shots are nasty), and never mind who and what could be spinning towards our little planet from a trillion miles away because frankly, as you pointed out, the odds are slim to none that we’ll be invaded and slimed on by a superastro-alien race (yes, I made that word up and whew, that was along sentence). And since we have no control over that or the earth shattering beneath us, we should just thank God we HAVE ground to stand on (for now)! Amen!?
You’re such a brainy nerd. I want to be like you when I grow up. 🙂
Fiji sounds fantastic, and I’d be happy with just fresh water to drink, as long as I had the sun and the sound of the waves and a stack of books! 🙂 Let’s go someday…
A stack of science books- no less!! And you could wake me from my sun-drenched dreams every 20 seconds or so and exclaim loudly about a fascinating new tidbit you came across. And I would reply with great enthusiasm about how cool it is! And I might even learn something!
btw- don’t tell anyone, but I do find this stuff interesting…
So, I’m curious…if we’ve only been down 7.6 miles, then how do ‘they’ know the core is solid? Or the next layer is liquid? 🙂 This is fascinating, btw…I’d totally dig science classes if you taught ’em. 🙂 Whole lot easier (and fun) to read and follow.
Ah, that’s the beauty of it…those other layers are our best guesses!
Here is a good explanation by a professor of geology. The short answer is: we guess based on seismic waves and how they react with what we can’t see, in comparison to how they react with matter on the surface.
http://www.soest.hawaii.edu/GG/ASK/earths_core.html
And thanks so much for your comment! That’s exactly the feedback I’m hoping for! I am trying to make science, which is so fascinating to me, interesting and fun. 🙂
You DO make the science stuff fun and interesting (which is saying a lot considering I flunked science–yes, all of them– in high school, and avoided them altogether in college).
Show off.
Beast.
Thanks for sharing the link, though!
So, I realize you’re reaching out to the “non-geeks” today….. But when you posted the estimated distance that Voyager is from Earth (10.8 billion miles!) I just had to pull out the calculator and see how fast it’s moving — about 36,000 miles per hour on average over the last 34 years. Holey moley, Batman!
Yes, I am guilty of “geekdom”, as charged…..
Fly it proud, Dan…
Just for you, I added a hyperlink to the NASA report that showed the distance traveled. I need to do more hyperlinks in my posts, so people don’t think I’m making this stuff up…:-)
And especially for you, since you are sitting on the edge of the great drop off point.
Wait…so are you! 🙂
Cathy, I enjoyed this because I just heard that Richard Branson (Virgin Records, Airlines etc.) is currently having a submirine built to fully explore the Mariana Trench. The Navy dive only went to the floor of the “shallow end.” This whole thing fascinates me.
Yes, he is! I’m thinking about doing a whole post on him…he’s an interesting character! I love that you knew that.
Thanks for reading, and commenting. 🙂
Wow! This is so interesting! The supervolacano thing freaks me out, though!
I know! Me too. But I already seem to fret over so many things, I don’t think I have room for any more worries, especially one this big. Oh well. 🙂
Thanks for coming by!