Map scale

Northern Lights map: Where to see the Northern Lights this week

ACROSS AMERICA – People living in the northern part of the US states could see the Aurora Borealis later this week after a geomagnetic storm kicked the solar plasma producing the Aurora Borealis towards the Earth’s magnetic field.

If this storm dies out or you miss it, your chances of seeing the Northern Lights are greater than ever right now. The reason: Solar Cycle 25. It’s an 11-year cycle in which the sun’s magnetic fields reverse polarity, causing solar storms 93 million miles from Earth with much more frequency over the next decade.

There is some difference of opinion on when the dazzling auroras may be visible. NASA has issued a warning for Wednesday evening, while the Space Weather Prediction Center – a branch of the National Oceanic and Atmospheric Administration – expects Thursday to offer the best chance of seeing the Northern Lights.

NASA predicts a faster solar storm that would hit our planet’s magnetic field harder, space weather physicist Tamitha Skov said on Twitter.

Where to see the Northern Lights

Either way, states in the Upper Midwest have the best chance of seeing the aurora, Skov said. The auroral oval surrounding the geomagnetic poles dips downward, explaining why someone in northern Minnesota can see the aurora but they’re not visible to someone at the same latitude in upstate from Washington.

The Kp index is a 10-point scale used to characterize the magnitude of a geomagnetic disturbance. Areas above the green line have the highest chance of seeing the Northern Lights. (Graphic by NOAA Space Weather Prediction Center)

Monday’s solar flare was an M4 strength event on a scale of M1 to M9. M-class solar flares are the second largest type and are capable of producing brief radio blackouts in the Earth’s polar regions.

During geomagnetic storms, the ovals move away from the poles and provide some lucky people in the United States with an ethereal sky show they will never forget. During particularly strong storms, people in latitudes as low as Pennsylvania, Oregon and Iowa can see the lights.

The science behind the aurora – in the southern hemisphere they are called the aurora australis – is complicated. During solar storms, the sun emits electrically charged ions that travel away in a stream of plasma, an ionized gas, known as “solar wind”. The vivid colors glow as plasma hits Earth’s ionosphere about 60 to 80 miles above the planet’s surface.

As the National Weather Service explains, the lights glow “in the same way that a neon sign glows when electrons pass through an inert gas.”

What NASA expects to learn

Aurora borealis exposures are favored in cold regions near the poles, but the energy exchange that causes them is a significant source of heat, according to NASA, which plans to blast two rockets through an active aurora to find out more.

Life on our planet exists in the troposphere, Earth’s lowest atmospheric layer, and the air we breathe is made up of neutral, magnetically balanced atoms and molecules with all of their electrons, NASA explained.

“But hundreds of miles above us, our air begins to fundamentally change character,” the space agency said on its website. “Energized by the Sun’s unfiltered rays, electrons are stripped from their atoms, which then take on a positive charge. A once neutral gas transforms into an electrically reactive state of matter called plasma.”

The transformation of plasma into neutral gas takes place in an extended atmospheric boundary layer where the two mix. The winds send the particles flying in different directions, and when they collide, interesting physical results, according to NASA.

“Friction is a great analogy,” said Stephen Kaeppler, assistant professor of physics and astronomy at Clemson University in South Carolina and principal investigator of the NASA mission, in a blog post on the website. of the agency.

“We all know we’re rubbing our hands together, you’re going to get hot,” he said. “It’s the same basic idea, except we’re dealing with gases instead now.”

Friction is a constant in the boundary layer where the neutral atmosphere and plasma meet, but active auroras intensify everything.

“It’s like storming the football field after a college game,” Kaeppler said. “People at the top of the stadium are running towards the pitch, and as you get closer to the pitch, the crowd gets thicker and thicker. That’s how electrons deal with the increasing neutral density of the upper atmosphere. “

The window for launching the rockets in rapid succession from Poker Flat Research Range in Alaska opened last week.

So far, conditions have not been favorable for ion-neutral coupling during the Active Aurora, or INCAA, mission. Scientists hope to find out how or if the aurora changes the position of the boundary layer where electrically charged and neutral air meet.

This could bring the boundary layer closer to the ground, lift it higher, or even cause it to fold in on itself. Each of the three possibilities could influence how our planet exchanges energy with the space around it.

“All of these factors make it an interesting physics problem to examine,” Kaeppler said.