Not all galaxies are spirals! I Zwicky 18 is an irregular dwarf galaxy smaller than our own, located 59 million light-years away. Two bursts of star formation lie at its heart, surrounded by wispy bubbles of gas formed by winds and radiation from hot, young stars within. This galaxy's content of elements heavier than helium is one of the lowest of all known galaxies in the local universe — making it similar to some of the first star-forming galaxies in the early universe. Scientists are…