NASA’s Solar Dynamics Observatory captured this image of a mid-level solar flare on the Sun — as seen in the bright spot in the lower centre of the solar disc on 24 August 2015. The image shows a subset of extreme ultraviolet light that highlights the extremely hot solar material, which is typically colourised in red. Image credits: NASA/SDO.The Sun emitted a mid-level solar flare, peaking at 8:33am BST on 24 August 2015. NASA’s Solar Dynamics Observatory, which watches the Sun constantly, captured an image of the event. Solar flares are powerful bursts of radiation. Harmful radiation from such a flare cannot pass through Earth’s atmosphere to physically affect humans on the ground, however — when intense enough — they can disturb the atmosphere in the layer where GPS and communications signals travel.
To see how this event may affect Earth, please visit NOAA’s Space Weather Prediction Center, the U.S. government’s official source for space weather forecasts, alerts, watches and warnings.
This flare is classified as an M 5.6 class flare. M-class flares are a tenth the size of the most intense flares, the X-class flares. The number provides more information about its strength. An M2 is twice as intense as an M1, an M3 is three times as intense, etc.
This week the Sun was hitting its lowest level of solar activity since 2011 as it gradually marches toward solar minimum. See a near spotless Sun revolve in this video from the Solar Dynamic Observatory.
With the transit of Mercury just two days away, interest in this comparatively rare event is growing fast. Given the favourable timing of this 7½-hour phenomenon for the UK, many will be able to view it at lunchtime or after work. If you don’t have suitably equipped telescope, join one of the many transit-viewing activities hosted by astronomical organisations nationwide.
