Major Solar Flare Erupts, May Make Auroras Visible in Northern U.S.

The sun unleashed a powerful Class X1.5 solar flare on March 9, 2011, a solar storm that could supercharge Earth's auroras.
The sun unleashed a powerful Class X1.5 solar flare on March 9, 2011, a solar storm that could supercharge Earth's auroras. The flare was recorded by NASA's Solar Dynamics Observatory and other spacecraft. Here, it appears in white at the upper right of the sun as seen by the Solar Dynamics Observatory. (Image credit: NASA/SDO/GSFC)

The sun unleashed another major solar flare Wednesday (March 9), a solar storm so powerful it could spawn dazzling northern lights displays that could be visible from even New York City.

The solar flare erupted at 6:23 p.m. EST (2323 GMT), letting loose a wave of charged particles that is aimed straight at Earth and should arrive in the next few days.

When it does, it could super charge the Earth's aurora borealis – also known as the Northern Lights – when the particles interact with the planet's magnetic field and atmosphere.  [Photos: Dazzling Auroras Seen by Northern Observers]

"This flare could make the Northern Lights visible as far south as Washington State, central Idaho, northern Wyoming, the Dakotas and east to Chicago, Detroit, NYC and Boston," explains's skywatching columnist Joe Rao. "Of course, we have to hope that the subatomic particles emitted by the flare arrive at the Earth's vicinity during the nighttime hours and of course, that skies are clear!" 

Predicting the effects and arrival time of solar storms is very difficult, however, so while the light storm could reach Earth tonight (March 10) it's not certain it would be visible so far south. Also, bright city lights could render the sky show difficult or impossible to see.

NASA space physicist James Spann took this stunning picture on March 1, 2011 from Poker Flat, Alaska, where he was attending a scientific conference to study auroras. (Image credit: NASA/GSFC/James Spann)

Powerful sun storm

The mega sun storm registered as a Class X1.5 event– one of the most powerful types of flares – and erupted from a region on the sun near a sunspot called 1166.

It is the second solar flare of this magnitude to occur in the last month.  A Class X2.2 storm erupted from the sun on Feb. 14 and was the most powerful solar flare in more than four years.

Space weather trackers classify solar flares in three classes: C, M and X. The weakest types of solar flares are Class C storms, with Class M tempests registering as medium strength, but still powerful, according to a NASA description. The Class X storm is the most powerful type of flare. [Amazing Sun Photos from Space]

In addition to radiation, solar flares can kick up massive eruptions of charged particles and magnetic plasma in what scientists call a coronal mass ejection.

According to, a website that monitors space weather and skywatching events, Wednesday's flare may only be the beginning.  The National Oceanic and Atmospheric Administration is predicting similar events for upcoming days.

"After four years without any X-flares, the sun has produced two of the powerful blasts in less than one month: Feb. 15th and March 9th," wrote.  "NOAA forecasters estimate a 5 percent chance of more X-flares during the next 24 hours."

When aimed in Earth's direction, strong solar flares can potentially disrupt satellites and power grids, as well as pose a hazard to astronauts on spacecraft. They can also spark dazzling shows of the northern lights, or aurora borealis.

"An X1/2B flare certainly has the potential of producing bright auroras across southern Canada and the northern United States," Rao said.

NOAA space weather officials measure aurora activity using a scale called a planetary K-index, which rates activity levels from zero to nine. Aurora activity from this latest solar flare could reach a K-7 on that scale, Rao explained.

That suggests northern lights activity could be visible across much of Canada and the uppermost states in the United States, according to a NOAA graphic.

A more active sun

The sun has been extremely active over the last month.

In addition to the major X2.2 class flare on Feb. 14, a powerful storm on Feb. 24 unleashed what NASA scientists called a "monster prominence" – a huge tendril of magnetic plasma – from the surface of the sun.

Between Feb. 24 and Feb. 28, NASA's twin Stereo satellites observed an intense coronal mass ejection erupted from the sun's far side, flinging an enormous tongue of plasma out into space. That storm, however, occurred on the opposite side of the sun from Earth, so it posed no threat to satellites, spacecraft, communications and power grids or other terrestrial infrastructure.

The STEREO (Ahead) spacecraft caught a large coronal mass ejection as it roared away from the Sun and out into space in the opposite direction from Earth (Feb. 26-28, 2011). (Image credit: NASA/Stereo/GSFC)

Another major storm erupted on March 7 from the region near a sunspot called 1164. That solar eruption kicked up material at a super-fast rate. The plasma wave was measured at a speed of about 1,367 miles per second (2,200 kps) – about 4.9 million mph – making it the fastest coronal mass ejection seen since 2005, according to

NOAA officials said the charged particles from that sun storm event should be reached Earth by today (March 10).

The sun is currently in the midst of an active phase of its 11-year solar weather cycle. The current sun weather cycle is known as Solar Cycle 24.

You can follow Managing Editor Tariq Malik on Twitter @tariqjmalik.

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Tariq Malik

Tariq is the Editor-in-Chief of and joined the team in 2001, first as an intern and staff writer, and later as an editor. He covers human spaceflight, exploration and space science, as well as skywatching and entertainment. He became's Managing Editor in 2009 and Editor-in-Chief in 2019. Before joining, Tariq was a staff reporter for The Los Angeles Times covering education and city beats in La Habra, Fullerton and Huntington Beach. In October 2022, Tariq received the Harry Kolcum Award for excellence in space reporting from the National Space Club Florida Committee. He is also an Eagle Scout (yes, he has the Space Exploration merit badge) and went to Space Camp four times as a kid and a fifth time as an adult. He has journalism degrees from the University of Southern California and New York University. You can find Tariq at and as the co-host to the This Week In Space podcast with space historian Rod Pyle on the TWiT network. To see his latest project, you can follow Tariq on Twitter @tariqjmalik.