Figure 11-10 RIVUXG A Star Cluster with an H II Region The star cluster M16 is thought to be no more than 800,000 years old, and star formation is still taking place within adjacent dark, dusty clouds. The inset shows three dense, cold pillars of gas and dust silhouetted against the glowing background of the red emission nebula (called the Eagle Nebula for its shape). The pillar at the upper left extends about 0.3 pc (1 ly) from base to tip, and each of its “fingers” is somewhat broader thanour entire solar system.