The middle of summer may not be the best time for a steaming pot of tea, but that’s just what the night sky offers. The brightest stars of Sagittarius, which is in the south at nightfall, form the outline of a teapot. And the hazy Milky Way seems to form puffs of steam from the spout. The puffs are a combination of bright stars and gas, and dark clouds of dust in the disk of the Milky Way Galaxy. And if you look deeply into those puffs, you’ll see quite a few other little puffs of matter — star clusters and the vast clouds known as nebulae. Two famous ones are directly above the spout, by about the width of your fist held at arm’s length — the Lagoon Nebula and the Trifid Nebula. The Lagoon is a stellar nursery — a cloud of gas and dust that’s dozens of light-years across. It’s given birth to scores of stars, with more taking shape even now. Through binoculars or a small telescope, it looks like a hazy oval of light. Photographs reveal a reddish-pink glow, which is produced by hydrogen
