Elephant’s Trunk

The trunk of an elephant extends 20 light-years across the constellation Cepheus, the king. New stars are taking shape inside the trunk — especially in the nostrils. But the supply of gas that gives birth to stars is being worn away, so the starbirth won’t last long.

The trunk is part of a giant complex of stars, gas, and dust known as IC 1396. It’s a few thousand light-years away. Even so, it’s so big that it spans about five degrees in our sky — 10 times the width of the Moon. And under dark skies, it’s bright enough to see with the eye alone. It’s high in the northern sky at nightfall.

The entire complex is illuminated by a system of three hot, giant stars. Their ultraviolet light causes gas in the surrounding nebula to glow. Winds from those and other stars are blowing away much of that gas and dust. But they’re also squeezing some of that material, causing it to collapse and form new stars.

That’s what’s happening with the elephant’s trunk. It’s a tall pillar of bright gas and dark dust, with a big blob at the tip. The trunk contains many stars that are no more than a hundred thousand years old — so young that they’re not actually full-fledged stars yet. The blob at the tip appears to hold a couple of stars that are slightly older.

Before long, all the gas and dust will be blown away or incorporated into new stars, and the elephant’s trunk will disappear.

Tomorrow: the demon star.
 

Script by Damond Benningfield