Formation and Evolution of Stars
The stars in the sky seem permanent and unchanging because it takes millions of billions of years for their lives to unfold. Stars are born in clusters within huge nebulas called star-forming regions. There, dark clouds of gas and dust collapse to form new stars. The most massive stars live the shortest lives, and never leave these stellar nurseries. Stellar winds and supernova explosions eventually blow away the leftover gas of the nebula, revealing the longer-lived stars of the cluster. These stars slowly drift away from one another, leaving no permanent record of their common origin.
Keywords: Astrophysics, Nebulae, Stars--Clusters, Stars--Evolution, Stars--Formation