The event that occurred Saturday April 3 caused auroras last week across Earth's polar region. Although officially classed as "weak," the ESA said the solar flare involved temperatures in the tens of millions of degrees.
"Significantly, this eruption was lined up with Earth, sending a vast number of charged particles hurtling towards us," ESA scientists said in a statement. Traveling at around 311 miles per second, the scientists said the front of the coronal mass ejection reached Earth the following Monday.
"The resulting geomagnetic storm was the most powerful in more than three years," the ESA said. "It provoked dazzling auroras, but no damage was reported to potentially susceptible systems such as satellites and … communications and electrical power infrastructure."