(CNN) -- Attention, Earthlings: The sun is spewing plasma toward you, and the results could be beautiful.
Stargazers looking to the sky late Tuesday night and early Wednesday morning could see northern lights, or aurorae. According to the Harvard-Smithsonian Center for Astrophysics, the potential light show started Sunday, when the sun's surface erupted and hurled tons of ionized atoms -- or plasma -- into space.
"This eruption is directed right at us, and is expected to get here early in the day on August 4th," said astronomer Leon Golub of the Harvard-Smithsonian Center for Astrophysics (CfA). "It's the first major Earth-directed eruption in quite some time."
When such an expulsion reaches Earth, it interacts with the planet's magnetic field and can create a geomagnetic storm, the CfA said. Solar particles stream down the field lines toward Earth's poles. Those particles crash with atoms of nitrogen and oxygen in the atmosphere, which then glow like little neon signs.
Sky watchers in the northern U.S. and other countries should look toward the north late Tuesday or early Wednesday for rippling "curtains" of green and red light, the CfA said.