As part of the geomagnetic storm brought on by Sunday's CME, which occurs when Earth is struck by a cloud of plasma, the northern lights, also known as the Aurora Borealis, are anticipated to illuminate the night skies of the northern US on Wednesday and Thursday night.
A coronal mass ejection (CME), the name for the plasma cloud, was released from the sun on Sunday. Since that time, the charged gas cloud has been hurling itself toward Earth.
After Sunday's CME was discovered, the Space Weather Prediction Center (SWPC) under the US National Oceanic and Atmospheric Administration (NOAA) announced on its website on Monday that G1 (minor) and G2 (moderate) storm watches were in effect for Wednesday and Thursday, respectively.
According to the SWPC, auroras could be seen over parts of the north-central states, the far Northeast, the far upper Midwest, and possibly the northwest corner of Washington state on Thursday as the cloud of charged gas is predicted to strike Earth with a glancing blow.
US Skies Wednesday, Thursday
MEs are frequently ejected from the sun's active regions, where strong magnetic field lines are entangled and bent. Massive amounts of energy are released as radiation and plasma when the magnetic field lines abruptly shift.
CMEs can lead to some problems, but they can also produce breathtaking auroras. The interplay of solar particles with the magnetic field of Earth results in auroras. The northern lights can also appear at much lower elevations than usual due to the large magnetic disturbances that CMEs can produce.
The SWPC predicts that auroras could be seen as low as Wisconsin, New York, and Washington state on Wednesday and Thursday; however, it will probably rely on how powerful the CME turns out to be.
There's also a chance that the auroras won't be visible because of light pollution, or cloud cover, or because they will not be happening at night. The SWPC did not provide information on precise timings, Newsweek reports.
Read also: Scientists Recreate Aurora Borealis in Lab to Understand How Northern Lights Are Formed
Aurora Borealis, The Northern Lights
An aurora is a type of natural light show that glistens in the sky and frequently appears as bright blue, yellow, red, green, and orange lights that shift and change shape subtly, much like softly blowing curtains. Auroras are visible to the naked eye only at night and typically only in the lower polar regions.
Near the Antarctic and Arctic Circles, which are located approximately 66.5 degrees south and north of the Equator, auroras can be seen almost every night. The display is known as the aurora borealis, or northern lights, in the north. It is referred to as the southern lights, or aurora australis, in the south.
The strongest solar winds produce the auroras at their most active. While solar weather, or the change in temperature, or cooling and heating, of various parts of the sun, can change daily, the solar wind is typically fairly consistent.
Depending on the type of atoms involved and the altitude, the aurora has a variety of colors. In the higher parts of the atmosphere, ions can interact with oxygen atoms to produce a red glow.
The most common aurora, a green-yellow hue, happens when ions hit oxygen at lower altitudes, making this one unusual. Ions striking nitrogen atoms result in the reddish and bluish light that is frequently visible in the lower outskirts of auroras. Though we rarely can see this region of the electromagnetic spectrum with our eyes, ions hitting hydrogen and helium atoms can result in blue and purple auroras.
Related article: CMEs: Solar Particles Can Create Aurora Displays, But May Also Cause Worldwide Disruptions