Tag: space

Meteor vs. Meteorite vs. Meteoroid

If you are not an astronaut  or some other kind of space geek, chances are you have no idea what’s the difference between meteor, meteorite and meteoroid.  If you are anything like, you probably use meteor and meteorite interchangeably.  Apparently, there is quite a specific difference.  Here is an easy to understand description from the Mental Floss:

Say you’re a bit of interplanetary dust or debris trucking through the vacuum of space, minding your own business. You’re not very big. Certainly not big enough to be called an asteroid. In fact, you might just be a speck of dust or even smaller. Congrats! You’re a meteoroid!

But say, for example, a bright blue planet suddenly gets in your way and sucks you in, and before you know it you’re streaking through an atmosphere so fast that you ablate (fancy way to say “vaporize”) and let off a bright streak of light. You are now officially a meteor.

Now, on the other hand, if you started out big enough, then enough of you will emerge from this furnace o’ friction to hit the ground in some farmer’s field, making you a meteorite.

Earth photos from ISS

I think I’ve linked to some of these images before, but there is definitely more now and they are so beautiful that I’m sure nobody will mind looking at them again.  These are some breathtaking photographs of our planet Earth from the International Space Station (ISS).  The pictures are in three parts: part 1, part 2, part 3.  Enjoy!

Richat Structure

Last week I posted a couple of photographs of Cyprus from space.  While looking through the rest of the images in collection, I noticed something that I’ve never heard about before – a picture of so called Richat Structure.

If you, like me, haven’t heard about it or heard and totally forgot, here is a brief Wikipedia summary that should get you started.

The Richat Structure, also known as the Eye of the Sahara, is a prominent circular feature in the Sahara desert of Mauritania near Ouadane. It has attracted attention since the earliest space missions because it forms a conspicuous bull’s-eye in the otherwise rather featureless expanse of desert. The structure, which has a diameter of approximately 50 kilometres (31 mi) and is located 400–450 metres (1,310–1,480 ft) above sea level, has become a landmark for space shuttle crews.

Initially interpreted as a meteorite impact structure because of its high degree of circularity, it is now thought to be a symmetrical uplift (circular anticline or dome) that has been laid bare by erosion. Paleozoic quartzites form the resistant beds outlining the structure. The lack of shock metamorphism at the site further backs the latter claim.