Looking Up: Asteroids, Moon Rocks, And Meteorites . . . Oh My!

Oct 15, 2018

Dawn spacecraft
Credit NASA / JPL-Caltech / MPS / DLR/ IDA / PSI / nasa.gov

This week Hal takes a "vested" interest in space rocks of all kinds.

Have you ever touched a rock that was not of this Earth? If you visited the National Air and Space Museum in Washington, DC, you may well have stood in line to touch the moon rock they have on display in the great hall. But other than that, have you touched a moon rock? A rock from Mars? Or even an asteroid?

Well, maybe.

That’s because, way back before there was life on Earth, there was a time in our Solar System known as the Great Bombardment. Pretty much everything in the early solar system was getting smacked pretty regularly by big hunks of rock, asteroids, and more, that were zipping around. These collisions created the craters you see on the Moon and on other places in the solar system. And these hits were sometimes massive, and blasted hunks of rock out into space. These rocks floated around for billions of years, and every now and then, some of them would run into the Earth and become meteors. And some of these rocks made it to the surface to become meteorites. So, you can find a bit of, say, the Moon, stuck to Earth rocks. In fact, I have a small Moon rock myself.

The asteroid Vesta, about the size of Iowa, is high in the Colorado sky right now. It’s worth a look. And we have a spacecraft named Dawn, that spent a year in orbit around Vesta, analyzing its surface. And from that analysis, we now know that there are bits of Vesta on Earth! I saw one at a rock and gem show in Denver recently.

If you’d like to take a closer look Vesta, or any of the other wonderful and amazing things in the sky, please visit csastro.org for a link to information on our monthly meetings and our free public star parties.