Stargazers received a spectacular treat in parts of the U.S. and Europe on Thursday when the northern lights appeared in skies much farther south than they’re typically ever seen. The pink, purple, blue and green light show was documented in parts of England,

The Earth’s magnetic field shields us from much of it, but particles can travel down the magnetic field lines along the north and south poles and into Earth’s atmosphere. When the particles interact with the gases in our atmosphere, they can produce light — blue and purple from nitrogen, green and red from oxygen.