People in more than 15 states in the U.S. may be able to see the Northern Lights on Monday night.
Following a massive eruption of plasma from the sun—known as a coronal mass ejection (CME)—over the weekend, the National Oceanic and Atmospheric Administration’s (NOAA) Space Weather Prediction Center has issued geomagnetic storm watches for Monday and Tuesday, which could lead to colorful auroras.
NOAA issued its geomagnetic storm watches after the detection of a CME erupting from the sun on Saturday. A CME occurs when the sun releases an explosive burst of plasma and magnetic fields into space. Those ejections can then hit Earth hours or days later.
When a CME reaches Earth, the charged particles can react with molecules in the planet’s magnetosphere—the region around the Earth where its magnetic field lies—to produce a geomagnetic storm. Such storms in turn can create auroras, vibrant displays of light that can appear in a variety of colors depending on the gases struck by the solar particles and how high up in the atmosphere the collision occurs.
NOAA rates the severity of geomagnetic storms on a five-point scale, with G1 storms being considered “minor” and G5 storms “extreme.” Stronger geomagnetic storms increase the likelihood of auroras being visible closer to the equator.
The CME that exploded from the sun on Saturday is expected to reach Earth’s atmosphere on Monday. NOAA has forecast that it could produce a strong, G3-level storm on Monday and a moderate, G2-level storm on Tuesday.
During the day, any such light displays are blocked out by the sun and not visible. The geomagnetic storm resulting from the CME was forecast to be strongest on Monday between 11 a.m. and 2 p.m. ET, according to NOAA, with a G3 storm possible during that time.
Luckily, however, NOAA forecast that geomagnetic activity could remain high into Monday evening, with a G2-level storm possible up until 8 p.m. ET and the strength then gradually
