Saturday, September 27, 2008

Coming of age in the Milky Way


Before we leave yesterday's Eta Carinae Nebula panorama, take a closer look at the Caterpillar (click to enlarge). In the panorama, it is located just above dead center. This globule of gas and dust looks strikingly like the creature it is named for -- the stumpy legs, the eye, the antenna. Although it looks like a caterpillar, it is more properly a chrysalis; it is inside such dusty clouds that stars are born.

The Caterpillar is roughly a light-year long. If you set out to travel from end to end at the speed of a typical solar-system spacecraft, it would take about 50,000 years to make the journey.

How big a part of the sky does the Eta Carinae panorama cover? Hold this letter O at arm's length. It would cover the nebula, with the tiny Caterpillar floating within.

You tell me what it means to live in such a universe.