Space is full of dangers. The earth and its atmosphere do a great job protecting us from most of them. But sometimes these dangers are stronger than even these protective measures can withstand, and potentially catastrophic events can result. Some of the most famous potential catastrophic events are solar flares. While normal solar activity can be distracted by the planet’s magnetic field, resulting in sometimes spectacular polar lights, larger solar flares are a danger to watch out for. So it’s worth celebrating a team of researchers at the International Space Science Institute who have found a way to better track these potentially dangerous natural events.
Extremely large coronal mass ejections (CMEs) are relatively rare and when they happen they are usually not directed towards the earth. That was the case in 2012 when a massive solar flare missed Earth, but could have turned off power grids and destroyed satellites across an entire hemisphere of the planet.
UT video about the severity of solar storms.
Flares the size of 2012 are relatively easy to detect with conventional sensor methods due to their size, but also their positioning. These sensors can look for signs of brightening on the sun’s surface that might indicate a solar flare, or watch the solar flare itself transition from the sun into the darkness of space. Unfortunately, the same sensor techniques are unable to detect the main types of CMEs – those that are aimed right at us but do not cause any whitening.
These CMEs, which do not produce any tell-tale signs on the sun’s surface, are known as “stealth” CMEs. Usually we only notice these when they actually hit Earth and don’t have a good indication of where they originated on the sun. However, the researchers used data collected by NASA’s STEREO spacecraft from four stealth CMEs that actually traced them back to their origins on the Sun.
Anton Petrov’s video about the 2012 solar flare.
Credit – Anton Petrov YouTube Channel
When they then analyzed these points of origin with other data collected at the same time, they noticed a changing pattern of whiteness that occurred for all four stealth CMEs. They believe these changes indicate the emergence of the stealth CME and give scientists valuable time to identify a potential massive CME hit and prepare for it as soon as similar patterns are discovered.
However, recognizing the patterns themselves can prove difficult. STEREO’s work in finding the source region of the CMEs used in the study was just happy – the spacecraft happened to be looking in the right place at the right time. To fully work out this technique, more data from an offset angle from the earth is needed to model the structure of the newly found CME and its region of origin.
The STEREO twin probe monitors the sun for solar storms in this artist’s impression.
Credit – NASA
But help is on the way – last year ESA launched the Solar Orbiter, which is supposed to collect the necessary data as part of its mission. It can also help with an even more difficult problem – the detection of “super-stealth CMEs” that do not appear on a coronagraph, a standard tool used to detect other types of solar flares.
Understanding is key to defeating, or at least managing, this potentially deadly environmental threat. Now we have a tool to predict more of these dangers and a way forward to spot more of them.
Limits – New method predicts “secret” solar storms before they wreak geomagnetic devastation on Earth
Frontiers – Investigation of remote sensing techniques to detect stealth coronal mass ejections
The Sun – Nasa boffins try to solve the mystery of the “secret solar flares” that break out without warning
UT – Do waves on the sun’s surface tell us a flare is coming?
Images showing the four CMEs used in the study.
Credit – Palmerio, Nitta, Mulligan et al.