This artist's conception shows a young, hypothetical planet around a cool star. A soupy mix of potentially life-forming chemicals can be seen pooling around the base of the jagged rocks. Observations from NASA's Spitzer Space Telescope hint that planets around cool stars -- the so-called M-dwarfs and brown dwarfs that are widespread throughout our galaxy -- might possess a different mix of life-forming, or prebiotic, chemicals than our young Earth.