Asteroid 2012 DA14 Comes Calling on Friday

This Valentine’s Day is a real treat for me.  Not because I am spoiled by my husband (I am), or because I am particularly loveable (between errors and attitude, I really am not) but because the next day I get to enjoy an astronomical treat.  Studying the stars makes me feel both very small and very big.  Being married to an amateur astronomer feeds this passion in a big way.  There is nothing like an article from Sky and Telescope to give you the real nitty gritty on what is going on in the celestial neighborhood.  Friday, we are getting an interesting drive-by from a potentially dangerous, but actually harmless space visitor.

Asteroid 2012 DA14 will not be destroying the earth.  It won’t even be creating any minor chaos.  But it will come close enough to give us pause.  This asteroid is a 150 feet long, about 1/2 the length of a football field.  It is also 50 feet longer than the asteroid that produced the famous Tunguska Explosion over Siberia in 1908.  That asteroid exploded in midair, leveling trees and producing death and destruction over an 835 square mile region. 

            Don’t worry, Asteroid 2012 will be the closest fly-be of an object this size that we know of, but it will not be a threat to us.  In fact, our gravity will impact its orbit in such a way as to send it farther from us in future passes.  Like most comets and asteroids, this space rock was discovered by amateur astronomers.  They are the devotees who spend so much time looking at the Heavens that they are much more likely to find these space sojourners than the professionals who tend to concentrate on very specific deep sky objects. 

            2012 will come as close as 17,200 miles from earth, with its closest point over the island of Sumatra in Indonesia.  That distance is close—really close.  The moon is 13 times farther away than the asteroid will be.  In fact, the geosynchronous satellites that report to your GPS are farther from earth than this asteroid.  Those satellites are about 22,000 miles above us.  The asteroid will be inside that satellite line.  Like I said, its close!

            We are visited by these asteroids about every 40 years and one impacts the earth about every 1200 years.  This won’t be one of them.  Nor will you be able to see this visitor with the naked eye.  It is small, especially compared to the asteroid that killed off the dinosaurs 65 million years ago.  That bad boy was about 6 miles in diameter.   But this asteroid will breeze past us, unnoticed unless you tune in NASA, which will be live streaming the fly-by. 

            Many asteroid bits, some fist size, others nothing but dust, have added their weight and substance to the earth since our beginning.  We owe them a debt.  Asteroids are remnants of our early solar system.  Most of them are located in the asteroid belt between Mars and Jupiter, a kind of DMZ separating the smaller rock planets from gas giants of our solar system.  It is in studying asteroids that we have learned that our solar system is approximately 4.567 billion years old.  What is amazing is that these rocks contain significant amounts of amino acids—the building blocks of life.  There is a very real possibility that life on this planet evolved from primitive proteins delivered here by asteroids first created at the dawn of our solar system.  We are, indeed, the stuff of stars.   

            Enjoy the music of the spheres, and keep the faith.