Along with astronauts aboard the International Space Station, skywatchers around the world were treated to a stunning light show on St. Patrick's Day--thanks to a severe geomagnetic storm that hit Earth.
(Scroll down for photos.)
The geomagnetic storm that triggered Tuesday's auroras resulted from a stream of charged particles sent our way by a pair of massive eruptions that the sun released on Sunday. At its peak, the storm reached a G4-level intensity on a one- to five-point scale.
Auroras occur when charged particles from the sun collide with particles in Earth's atmosphere, triggering a reaction that releases light. Auroras are typically seen over Earth's poles but can drop down toward the Equator during intense geomagnetic storms.
See below for a collection of 15 gorgeous stills and videos of auroras seen across the U.S., Canada, and northern Europe--and from the ISS. Enjoy!
Last night Earth experienced a geomagnetic storm and aurora were visible in the Northern U.S. states. These images of aurora were captured on March 17, 2015, around 5:30 a.m. EDT in Donnelly Creek, Alaska by Sebastian Saarloos. Image Courtesy of Sebastian Saarloos.
— Oğuzhan Kaya (@oguzhankaya_ok) March 18, 2015