Eyes to the skies this weekend for a chance to see the brilliant Northern Lights.
In the early hours of July 21, a solar flare erupted from an active sunspot on the Sun’s surface. The flare was relatively weak, causing a “solar tsunami” that spread far from the sunspot.
A fast but diffuse CME appeared from the Sun from the central disk ~0100Z on the 21st, producing a faint halo in the COR images. This means a solar storm is in transit, headed straight for Earth and should arrive on the 23rd. What does the data and forecast show? Let’s talk about it!
A fast but diffuse CME appeared from the Sun from the central disk ~0100Z on the 21st, producing a faint halo in the COR images. This means a solar storm is in transit, headed straight for Earth and should arrive on the 23rd. What does the data and forecast show?
Let’s talk about it! ⤵️ 🧵 💫 Sara Housseal 💫 on Twitter: “The Sun had a fast but diffuse CME from the central disk ~0100Z on the 21st, producing a faint halo in the COR images. This means a solar storm is in transit, headed straight for Earth, and should arrive on the 23rd. What does the data and forecast show? Let’s talk! ⤵️ 🧵 pic.twitter.com/sP6zNRUNT2 / Twitter”
— 💫 Sara Housseal 💫 (@SNHWx) 💫 Sara Housseal 💫 on Twitter: “The Sun appeared a fast but diffuse CME from the central disk ~0100Z on the 21st, producing a faint halo in the COR images. This means there there’s a solar storm in transit. , headed straight for Earth, and should arrive on the 23rd. What does the data and forecast show? Let’s talk! ⤵️ 🧵 pic.twitter.com/sP6zNRUNT2 / Twitter”
At the same time, it also caused a “coronal mass ejection” into space. This cloud of charged solar particles, sometimes called a “solar storm,” was more or less aimed directly at Earth.
Large Coronal Mass Ejection (CME) recorded by SOHO/LASCO. Estimated speed: 1355 km/s. Simulations suggest it will hit Earth on 2022-07-22T16:38Z (plus or minus 7 hours). The maximum Kp index could reach 8-9 (severe to extreme). pic.twitter.com/XrL7pOEl9B
Large Coronal Mass Ejection (CME) recorded by SOHO/LASCO. Estimated speed: 1355 km/s. Simulations suggest it will hit Earth on 2022-07-22T16:38Z (plus or minus 7 hours). The maximum Kp index could reach 8-9 (severe to extreme). SOHO_Mission on Twitter: “Large Coronal Mass Ejection (CME) recorded by SOHO/LASCO. Estimated speed: 1355 km/s. Simulations suggest it will impact Earth on 2022-07-22T16:38Z (plus or minus 7 hours). Maximum L “Kp index could reach 8-9 (severe to extreme). pic.twitter.com/XrL7pOEl9B / Twitter”
— SOHO_Mission (@MissionSoho) SOHO_Mission on Twitter: “Large Coronal Mass Ejection (CME) as recorded by SOHO/LASCO. Estimated speed: 1355 km/s. Simulations suggest it will impact Earth on 2022-07-22T16:38Z (at plus minus 7 hours). Max Kp index could reach 8-9 (severe to extreme). pic.twitter.com/XrL7pOEl9B / Twitter”
The CME is expected to sweep us by Friday night. When it does, it can cause a geomagnetic storm around the planet. This means we could see auroras.
How bright the auroras and how far south they are visible will depend on how strong this geomagnetic storm is.
Although the solar flare was weak and the coronal mass ejection rather diffuse, according to NOAA’s Space Weather Prediction Center, when the CME impacts are combined with the effects of the solar wind, it could produce G1 ( minor) or even G2 (moderate). , stormy conditions overnight Friday into Saturday.
The geomagnetic storm watch combines the effects of two coronal holes with the incoming CME, to report possible space weather impacts overnight Friday. Credit: NOAA SWPC
NOAA SWPC classifies geomagnetic storms as one of five classes: G1 (mild), G2 (moderate), G3 (strong), G4 (severe), and G5 (extreme). Gravity is based on the predicted density, energy and speed of the CME. The potential impacts, for auroras and effects on our technology and power grids, increase with each successive rank.
If a small geomagnetic storm results from this encounter, auroras will likely be visible in the northern regions of eastern Canada and the Prairie Provinces.
In the map below, a G1 (minor) storm tends to have auroras that extend as far south as the green line.
On this map, the colored arcs indicate how far south the northern lights can normally be seen, depending on the geomagnetic conditions around Earth.
During a G2 (moderate) geomagnetic storm, auroras can be seen as far south as between the yellow and green lines. So it’s possible for sky watchers in southern Ontario to spot them, although they’re usually not bright enough to be seen through city light pollution.
Depending on what happens, there may even be some residual effects on Saturday night, which could produce a second night of auroras.
Thumbnail image provided by Alberta aurora chasers Tree and Dar Tanner.