The swallows are coming back to Capistrano. A week-long celebration kicks off today at Mission San Juan Capistrano, where the little birds have migrated for decades.
It won't get much attention, but another visitor from above descended on the California town 35 years ago tonight: a meteorite -- a rock from beyond Earth. It crashed into the roof of a carport and split into two pieces. The owners found the biggest piece the next morning on the floor of the carport. They found a much smaller piece about a month later while cleaning the gutter.
The pieces didn't add up to much -- about two ounces in all. But the meteorite represents a treasure to scientists, because it helps them understand more about the early solar system.
The San Juan Capistrano meteorite is classified as a chondrite. That means it contains small bits of rock that long ago melted then resolidified. Astronomers believe that chondrites formed at the same time as Earth and the other planets of our solar system. As a result, they may reflect the composition of the original cloud of gas and dust from which the planets formed -- four and a half billion years ago.
This meteorite is especially valuable because it was picked up within hours of landing, so scientists know it wasn't changed by exposure to Earth's atmosphere. It should preserve a good sampling of the materials present at the birth of the planets.
Script by Damond Benningfield, Copyright 2003, 2008
For more skywatching tips, astronomy news, and much more, read StarDate magazine.