Clouds of gas and dust fill the space between the stars. Like giant puffs of smoke, these cosmic particles have a tendency to obscure objects from detection. But by using NASA's Spitzer Space Telescope, researchers can look through the clouds and see the heat radiated from distant stars, planets and even other galaxies. Since 2003, the telescope has utilized wavelengths in the infrared spectrum to uncover a hidden universe of never-before-seen places and phenomenon. Here are five mind-blowing images of the Milky Way taken by Spitzer.