Cape Cod residents looking northward toward Plymouth Sept. 12 around 9 p.m. may have noticed strange curtains of green, pink and purple illuminating the night sky.

Stunning rare display visits Cape Cod  

Cape Cod residents looking northward toward Plymouth Sept. 12 around 9 p.m. may have noticed strange curtains of green, pink and purple illuminating the night sky. No, the landscape was not “glowing green” around Plymouth’s nuclear power plant; instead, locals were treated to a rare display of the elusive “northern lights,” known in the Northern Hemisphere as the aurora borealis.

The aurora borealis, known in the Southern Hemisphere as the aurora australis, results from disturbances in the earth’s magnetosphere, which acts as a force field that protects the earth from harmful radiation from the sun (like a natural sunscreen). Without the magnetosphere, life on earth would cease to exist.

This radiation normally does not impact the Earth, but strong storms on the sun can seriously disrupt the magnetosphere.

Solar storms are born in “sunspots,” dark areas on the sun that are most common every 11 years or so, at the peak of the solar cycle. These sunspots can hurl harmful bursts of radiation, with the ensuing “solar storm” occasionally directed toward the Earth.

In addition to sparking displays of the northern lights, strong solar storms can deliver high amounts of harmful radiation to astronauts, dramatically increasing their risk for cancer. The most intense storms, categories 3, 4 and 5 (on a 0-5 scale), can severely disrupt GPS satellites, power systems and radio waves here on Earth.

In addition to igniting the spectacular displays of the northern lights that graced the Cape and Islands, the electromagnetic radiation associated with solar flares of this magnitude has been known to disrupt electrical grids at high latitudes.

In 1989, a solar flare knocked out power to millions of people in Ontario and Quebec, Canada; nowadays, officials at the Space Weather Prediction Center in Boulder, Colorado, can issue warnings to electrical companies to perform “manual shutdowns” to prevent damage to the infrastructure.

Two solar storms last week contributed to propelling magnetic energy as far south as the Cape, with one of the flares topping the charts as an “X-class” eruption, the strongest possible. The first of the two strong coronal mass ejections, or “solar flares,” erupted from the surface of the sun Sept. 8, but was dwarfed by the massive burst of energy that exploded earthward Sept. 10. While neither surge of energy was enough to produce the impacts that Earth felt, the two flares interacted in such a way that their energy “overlapped” enough to yield an impressive solar storm.

With our advancing technology, however, Earth has become more and more susceptible to the threat of a solar storm knocking out satellite capabilities.

Back in 1859, for instance, a strong solar storm topped the charts as the strongest such event known in recorded history. Telegraph operators stood in awe as their wires literally began to emit sparks as the aurora borealis dipped all the way to Cuba and Hawaii. One observer in Washington, D.C., recalled being able to comfortably read a newspaper at midnight, with everything illuminated by the intense green lights that persisted all night. Superstitious people interpreted the light as a harbinger of doom, while others attributed the lights to the “reflections of the shields of deceased soldiers.”

Similar displays of the northern lights are likely to sporadically occur in the coming months, as the sun nears the peak of its solar cycle. At this point, solar activity is expected to reach its greatest level in the past 22 years. During the peak of the last solar cycle in 2003, a severe solar storm caused aurora levels to linger in the “extreme” level for 12 hours on Oct. 29, dazzling sky watchers as far south as New Mexico.

 Matthew Cappucci is a senior at Sturgis Charter Public School. You can catch his forecasts three times a week on Channel 99.