September 8 – How Thai The Moon

Today’s factismal: A meteorite exploded over central Thailand yesterday.

One of the great things about science is that there is always something happening. If it isn’t an erupting volcano, it’s a huge hurricane, or a sudden earthquake, or (best of all) a meteorite. But why are meteorites so cool?

A meteor streaks across the Earth, as seen from the ISS (Image courtesy Ron Garan, NASA)

A meteor streaks across the Earth, as seen from the ISS (Image courtesy Ron Garan, NASA)

Part of the reason is that they are both very common and exceedingly rare. Every year, nearly 42,000 meteorites hit the Earth which makes them very common. But most of those meteorites fall over uninhabited ocean or deserts or empty forests, which means that they are only seen by satellites (if that). And most of those 42,000 meteorites are very small and burn up in the atmosphere; only about 500 are big enough to make it all the way to the ground.

Where Earth has been hit by meteorites is a ten year period (Image courtesy NASA)

Where Earth has been hit by meteorites in a ten year period
(Image courtesy NASA)

The other cool thing about meteorites is that they come from so many different places. Most of them come from comets and are just about the size of gain of sand; these are responsible for the spectacular meteor showers we see, like the Quadrantids and Perseids.  Of course, not all of the meteors that we see come from comets; many are pieces of asteroids that have collided. And we have even found some fragments of the Moon and Mars that arrived in Antarctica as meteorites!

Right now, we think that the meteorite that exploded over Thailand yesterday came from an asteroid. As meteorites go, it was pretty spectacular. Classified as a bolide (i.e., “big and bright”), it was visible in the daylight sky for more than four seconds before exploding in a giant white blast about 62 miles up (which qualifies it as an astronaut).  As of now, no “strewn field” of debris has been found, which is not unusual; most meteorites are found in Antarctica simply because they are easy to spot agains the snow. But try finding a small chunk of space rock in the jungle! But the sound was definitely found; the roar of the meteorite and its explosion could be heard over three provinces inThailand!

The Great Daylight Fireball of 1972 (Image courtesy and copyright James M. Baker)

The Great Daylight Fireball of 1972 (Image courtesy and copyright James M. Baker)

Now if you’d like to help scientists learn more about meteorites, then how about spending some time looking at the sky each night? If you see a meteor, then just click on the NASA Meteor Counter app; the data you create will automatically be sent to NASA to help in their work! The app is available for free on iTunes and Google Play:
http://science.nasa.gov/science-news/science-at-nasa/2011/13dec_meteorcounter/

 

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s