NASA is Building a ‘Solar Shield’ to give protection to Power Grids from Space Weather [Republished]

They’re in the market, biding their time. Waiting patiently. And once you least expect it, they’re going to plunge you and everyone you care about into total darkness.

Luckily, we will be able to see solar storms coming from about 93 million miles away, and NASA is now within the technique of creating a ” Solar Shield” that are meant to be capable to minimize the wear to power grids as a result of electromagnetic disturbances inside the atmosphere and ground attributable to foul weather on the sun.

The threat to power grids during bad solar weather is called GIC, or geomagnetically induced current. When the sun ejects a giant coronal mass in our direction, the impact with our atmosphere shakes up Earth’s magnetic field. That generates electric currents from the upper atmosphere right down to the ground. These can cripple power grids, overloading circuits and on occasion melting heavy-duty transformers.

Those transformers are very necessary to keep the facility flowing. They’re also expensive, irreparable inside the field, and might take a year to switch. Meaning that a tremendous coronal ejection could knock down entire power grids for long stretches of time, grinding economies to a halt and making life more than a touch inconvenient.

But NASA has a plan to battle these blackouts with blackouts. If transformers are offline at the time the storm hits they can not be affected, so the trick is to decide where and when a storm is going to hit before it reaches the atmosphere. To do this, NASA’s SOHO and two STEREO spacecraft identify a coronal mass ejection (CME) heading toward earth and create a 3-D image of it, allowing researchers to characterize its strength and determine when it’ll hit.

Depending on the intensity of the CME, the trip from sun to Earth can take 24-48 hours. NASA would track the CME across the sky, with the pivotal moment coming about 30 minutes previous to impact when the storm comes screaming past the ACE spacecraft, something like 930,000 miles from Earth. Sensors aboard ACE gather more data on the storm’s speed, magnetic field, and density it is fed into computer models at NASA’s Goddard Space Flight Center.

With below 30 minutes until impact, NASA’s models calculate the places possibly to be impacted with dangerous GIC and utilities are notified with a view to pull their grids offline. This can cause a blackout inside the region, but only a short lived one. When the storm ends, the grids come again online and life goes on.

Solar Shield is experimental at this point, and its hard to understand how successful it is going to be, mainly because it hasn’t had the trial by fire it should see if it works. Solar weather has been fairly quiet this year, so the team hasn’t been ready to gather the information it needs. But considering we’re going into a period of increased solar activity (solar weather ebbs and flows cyclically) in an effort to peak in 2013, Solar Shield will likely get its chance soon enough. [ NASA Science News ]

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This post is tagged: coronal mass ejection, electric currents, electromagnetic disturbances, stereo spacecraft, upper atmosphere