ICYMI: Watch a Replay of Last Night’s Aurora Borealis

Photo via Wikimedia Commons

A rare G4, otherwise known as a "severe" geomagnetic storm, hit Earth on St. Patrick’s Day, beginning around 10 a.m. ET, according to the National Oceanic and Atmospheric Administration’s (NOAA) Space Weather Prediction Center.

Popular Science reported that a pair of coronal mass ejections, or CMEs, that left the Sun two days prior are now interacting with Earth's atmosphere and geomagnetic field, causing the geomagnetic storm.

In a press briefing on Tuesday, NOAA scientists said the two CMEs, which were at one point independent of one another, may have unexpectedly combined during their accelerating ascent toward Earth, which is potentially why the storm registered as a G4, with the scale going up to 5.

Although there was some fear that the storms would disrupt the electrical grid, create tracking problems on spacecraft, and cause issues with GPS and radio, NOAA did not receive any dramatic reports of problems. Instead, however, the storm caused a beautiful side effect: The aurora borealis, more commonly known as the Northern Lights, were visible much farther south than their usual range close to or above the Polar Circle (i.e. Alaska, Northern Canada, northern Russia, etc.).

For those who missed it, Space.com and the Slooh Community Observatory created a video of the aurora in Iceland, which had moments of bright green. This was an unusual color for the lights, but fitting considering the storm occurred on St. Patrick’s Day.