My theme this year is science. Specifically, recent discoveries in science: Last year I explored various fields and gave overviews of what they were all about, but this time I've decided to track down some interesting discoveries/recent developments in scientific fields and post about those. I'm also winging the challenge--not exactly by choice, but I'm looking forward to seeing what I can come up with on a moment's notice. (Hopefully our internet connection will stop acting weird and let me blog normally soon. Pages are taking minutes to load for some reason.)
But before we finally get to the actual content of my post, I'd like to give a shout-out to the creator of the A to Z Challenge, Arlee Bird. He's an amazing blogger and built a challenge that has allowed people to explore the web and get to know people they'd normally never find.
Now, for my first A to Z Challenge entry: Astrophysics and Asteroids
Astrophysics is the study of space and the universe, such as stars, planets, matter, energy, and practically everything that involves the world beyond Earth. It's the examination of how celestial objects form or self-destruct; it raises questions about what occurred and is occurring in the universe.
The universe, of course, includes asteroids. On February 15th this year, as you've most probably heard, an asteroid (a "superbolide", bolide referring to the bright light it produced) hit the atmosphere and exploded over the Ural Mountains in Russia, above the town of Chelyabinsk. The asteroid was around 17-20 meters across and had a total impact energy of 440 kilotons of TNT, though around 90 kilotons was released as light.
Astrophysics has helped determine the size, velocity, and the likelihood of such an event occurring again. The chances of another asteroid exploding in the atmosphere is not, in fact, as low as you might think; since much of Earth's surface area is uninhabited by people, these types of explosions may occur from every few decades (which is the shortest estimate) to about 100 years and just go unnoticed. More are being found these days due to sensors put in place for the detection of nuclear blasts.
One thing astrophysics can't do, however, is predict such asteroids in advance. They're too minute for current methods and technology to find before they strike the planet, though there are plans to build a new satellite that would orbit the Sun and could be capable of pinpointing the smaller objects.
Sources:
http://www.pbs.org/wgbh/nova/earth/meteor-strike.html
http://neo.jpl.nasa.gov/news/fireball_130301.html
http://science.nasa.gov/astrophysics/
http://io9.com/5985276/incredible-details-are-emerging-about-russias-chelyabinsk-meteor
Do you think there should be more effort put into defending Earth from asteroids?
If you're participating in the A to Z Challenge, what did you choose for letter A?
-----The Golden Eagle
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