Don’t peek at the answer until you’ve given this a good try! Then, scroll down a bit and the truth will be revealed to you.

(Image Credit: NASA)

What in the world is it? Inch worms on the move? Well . . . kind of. This image is evidence of what just might have been the greatest migration of all. It is a high resolution electron microscope image of what are believed to be possible microscopic fossils of bacteria-like organisms. But these fossils are not from Earth. They come from a rock known as ALH8400, which is by far the oldest known meteorite from Mars. Its age? 4.5 billion years!

Perhaps you’ve guessed the implication of this find. That’s right. These microbes hitched a ride to Earth on a rock from Mars. The rock was ejected from Mars after an asteroid impacted the planet 16 million years ago! The rock (with the microbes embedded in it) then drifted aimlessly through space — until it landed on Earth until 13,000 years ago. Now that’s a migration!

The tubular features in this image are less than a micrometer in size, or about 1/500th the diameter of a human hair.