Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

December 25, 1998

Explanation: If our Galaxy were a Christmas tree, planetary nebulae would adorn it like colorful lighted ornaments twinkling on a cosmic scale. Glowing shrouds of gas ejected by red giant stars, planetary nebulae like NGC 6578 (left) and IC 3568 last for a mere 10,000 years or so as swollen stellar giants are transformed into fading, cooling white dwarf stars. Meanwhile ... have a safe, happy holiday season and Best Wishes to all from APOD!