Bright solar flare brings promise of auroras across Canada
Sunday, July 16, 2017, 2:16 PM - A bright solar flare has exploded on the Sun, throwing out an immense cloud of solar particles into space. With part of this cloud having reached us Sunday morning, aurora watchers are anticipating a great show on Sunday night!
This story has been updated.
The Sun has continued its quiet progress towards solar minimum - the point in its 11 year cycle where it exhibits the lowest levels of sunspot activity - but on the way there, it can still produce a few surprises.
On Thursday night (early Friday morning, UTC), the larger of two sunspots currently visible on the Earthward side of the Sun blasted out a bright M2-class solar flare.
Three views of sunspot AR2665, from around 5:00 UTC Friday, July 14, 2017, during the peak of the solar flare. The top frame shows the sunspot itself, while the bottom frames show off the coronal loops surrounding the sunspot (in gold, on the left) and the intense release of energy (in green, on the right). Credit: NASA/SDO/Scott Sutherland
At the same time as the solar flare was blasting out X-rays, which caused a minor radio blackout over parts of Asia, it also released a massive cloud of solar particles - what's known as a coronal mass ejection.
This coronal mass ejection is mostly aimed ahead of Earth's orbital path, and thus the vast majority of it will miss us. As the cloud expands out into space, however, one end of it is projected to sweep past Earth.
Even as this swath of solar particles washes past us, much of it will simply be diverted around the planet, due to the protective effects of Earth's magnetic field. A significant portion of them, though, will become snagged within the field lines, and then funneled down into the upper atmosphere near the planet's poles, to produce bright auroras.
Currently, NOAA's Space Weather Prediction Center is reporting that the Earth-directed portion of the coronal mass ejection arrived earlier than expected. By their observations, we were already seeing G2 (moderate) geomagnetic storm levels as of mid-morning Sunday, and these are expected to persist throughout the afternoon.
This evening, storm levels are predicted to diminish slightly - to G1 (minor) geomagnetic storm levels - and then jump back up to G2 storm strength between 8 p.m. to 2 a.m. EDT. Afterwards, activity is expected to ramp down to sub-storm levels by Monday morning.
Based on all of this activity, auroras are expected to stretch down over most of Canada and the northern United States tonight, and likely visible as far south as between the Kp=5 (green) and Kp=7 (yellow) lines on the map below.
There is also a chance, during all of this G2 geomagnetic storm activity, that levels could briefly jump as high as G3 (strong), which would push visibility down over the Kp=7 line.
Remember that it takes reasonably clear and dark skies to see the auroras, far from the light pollution cast by urban environments. Auroras are also notorious for being random and flighty. Sometimes they can appear faint, only to be seen with long-exposure photography, while other times they can be bright and vibrant to the naked eye, and they can appear and disappear quite suddenly.
If you plan on getting out to watch, choose your location carefully and be safe. In most regions of the country, simply getting outside of your local community is typically good enough. For those living in southwestern Ontario and the GTA, areas north of Stratford, Guelph and Orangeville tend to be good for viewing, as are those areas to the east of Lake Simcoe and north of Peterborough (the shores of Georgian Bay usually provide excellent viewing!).
Provincial parks are an excellent resource for skywatching, even if you have to stick to the parking lot at night.
As always with these events, give your eyes some time to adjust to the dark - 30-40 minutes typically - or you will likely miss out on it. Avoid all bright sources of light - streetlights, car headlights, cellphone screens & camera flashes, etc - during that time, then look up and to the north to potentially see the auroras.
Watch Below: Theresa and Darlene Tanner relate their experiences with the Northern Lights and how they take such amazing photographs