The Prince George Citizen

Technologi­cal infrastruc­ture affected by space weather events. MUST CREDIT: NASA

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that provide electricit­y – like tripping a circuit on a massive scale.

The sun exploded again in July 2012, spewing material toward Earth at nearly 10 million kilometres per hour. This time the coronal mass ejection hit a NASA spacecraft called STEREO-A at full-blast. The spacecraft’s sensors were stressed, but they still managed to measure the solar particles, gusts of solar wind and the strength of the interplane­tary magnetic field.

A year after the explosion, in a paper published in the journal Space Weather, astrophysi­cists examined the STEREO-A data to answer a worst-case question. “What if that coronal mass ejection had occurred 10 days earlier, when the Earth was in the line of fire?” said Daniel Baker, a professor of planetary and space physics at the University of Colorado at Boulder and one of the authors of the study.

Their conclusion: If it had hit Earth, Baker and his colleagues wrote, there was a “very legitimate question of whether our society would still be ‘picking up the pieces.’”

In 2008, a National Academies of Sciences, Engineerin­g and Medicine report on the economic and societal impacts of space weather came up with a worst-case estimate for an extreme geomagneti­c storm: It could cost North America up to $2 trillion in the first year, and recovery would take four to 10 years.

It’s said that space weather science lags about 50 years behind terrestria­l weather forecastin­g. Meteorolog­ists know what conditions cause hurricanes, and they can spot the seeds of a storm brewing over the ocean long before it makes landfall.

But warning times for space weather events are often measured in minutes, Murtagh said, and there is too much we do not know.

“There’s a lack of understand­ing,” Murtagh said. “It’s science. It’s knowledge of the sun and the physical processes that are likely to produce those energetic particles. We just don’t fully understand the science yet.”

Much of our modern understand­ing of the sun stems from 91-year-old Eugene Parker, for whom NASA’s new probe is named.

In the mid-1950s, Parker discovered a link between two seemingly unrelated space mysteries. First, bizarrely, the corona, or atmosphere of the sun, is hotter than its surface – scientists liken the sun to a campfire that feels hotter the further one stands from the flames. And second, the dusty tails of comets always point away from the sun, as if blasted by a powerful wind.

Parker realized the corona is not a static halo, but a stream of material from the sun itself. It starts slow and dense and zooms up as it escapes the sun’s gravity, eventually exceeding the speed of sound. The pointed tails of comets behave like windsocks caught in the solar wind.

The accelerati­on of the particles in the solar wind remains one of the “fundamenta­l mysteries of the sun,” said Nicola Fox, a heliophysi­cist at the Johns Hopkins Applied Physics Laboratory and the project scientist for Parker Solar Probe. And it is one of the keys to understand­ing CMEs – the blasts that pose so much danger to life on Earth.

After the National Academies released its sobering 2008 report, “awareness, both at government and in the public, for this hazard really came to the fore,” said a Federal Emergency Management Agency official, who spoke on the condition of anonymity.

Trillion-dollar space storms are a rare issue that rallies Republican­s and Democrats alike. The Obama administra­tion’s executive order 13744 created a national space weather policy in 2016. FEMA recently finished drafting a federal operations plan for space weather that was sent to the Trump administra­tion for approval. Congress is also considerin­g legislatio­n directing funds toward developing a space weather plan.

The issue is particular­ly pressing for the East Coast of the United States between Washington and Maine, not only because of the extensive electric infrastruc­ture in this region. The very ground beneath our feet makes us vulnerable, Murtagh said. The 300 million-year-old igneous rock on which the Eastern Seaboard is perched does not conduct electricit­y well.

If a current strikes this rock, it will seek an easier path – like metal pipes, telephone wires and electric cables. Eventually, the current can hit high-voltage transforme­rs, the spine of the power grid, and overwhelm their magnetic cores.

This is not idle speculatio­n. It happened, on a relatively small scale, in Canada in 1989. The sun belched out a gas cloud in early March that cut off radio signals. (At first, some observers suspected Soviet, not solar, interferen­ce.) Electrical currents buzzed through the ground and flooded into the Hydro-Québec power plant. Six million people in Québec were without power for nine hours. Glancing effects were felt as far away as New Jersey, where the electrical surge roasted a transforme­r at the Salem Nuclear Power Plant.

Industry reports suggest operators would have enough time to shut down the grid before it suffered permanent damage. But others are not as optimistic.

That a future solar storm will blast Earth is not a question of if, but when. In 2012, Peter Riley, who studies the sun’s corona at Predictive Science Inc., a San Diego-based company that develops computer models of the sun, published an article in Space Weather that calculated the odds of a Carrington-scale repeat.

Within the next decade, he concluded, it could be about 12 per cent – on par with the risk of other 100-year hazards, like massive floods.

Over the next seven years, the Parker Solar Probe will embark on a series of 24 egg-shaped orbits around the sun, repeatedly swinging past Venus to reorient itself. Each close approach will shoot it through the corona at a breathtaki­ng 700,000 kilometres per hour.

 ?? CITIZEN NEWS SERVICE GRAPHIC VIA NASA ??
CITIZEN NEWS SERVICE GRAPHIC VIA NASA

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