Science News Review

Meanwhile, Some Chaos in the Neighborhood

Dec 22 at 5:05pm by Aileen

There have been some interesting events going on in our solar system since the turn of the new millennium, just coming up on being 8 years old (when counted as the New Year’s transition 2000 to 2001). And the most recent situation here on planet earth bodes ill for sunbathers and electronic communications.

Our sun (Old Sol) has a predictable 11-year cycle of magnetic pole-flipping - with accompanying sunspots and coronal mass ejections [CMEs] of high-energy ions. The most recent pole-flip occurred between 2000 (north pole) and 2002 (south pole). Our planet has also been known to flip its poles, but on a much longer period cycle that averages ~500,000 years. It’s been about 780,000 years since this last occurred, so it’s probably not too surprising that by 2004 scientists were noticing that our field was fading fast.

Back then scientists were fairly convinced that the process of field reversal takes hundreds or thousands of years to accomplish, so the panic level wasn’t high. Earth’s magnetic field produces a “magnetosphere” that shields the surface and lower atmosphere from incoming solar wind, CMEs and cosmic rays by directing them around the planet. Occasional solar radiation does break through and wreak temporary havoc to our electrical grids and communications technologies. And some birds, turtles and bees rely on the magnetic field of the earth in order to navigate.

In February of 2007 NASA launched five satellites collectively called THEMIS to study the earth’s magnetic field, and by May of that year rumors started appearing in the press that our field flip was imminent. That could present issues due to the likelihood that the magnetosphere may essentially disappear during the period of the flip, leaving the sunny side of the planet exposed and vulnerable. There are of course ample caveats in the scenarios for such an event, given the fact that modern humans have never actually experienced one. Obviously, there is good reason to keep an eye on the process, as 5 satellites aren’t cheap to invent and deploy just for the purpose…

Just this past week we have finally been informed by NASA that indeed, the five THEMIS satellites flew through a ‘hole’ in the magnetosphere’s sun-side bow wave just as it was opening on June 3 of 2007. The hole, NASA tells us, is now 10 times larger than any such hole previously believed to exist, 4 times wider than the diameter of the planet. NASA’s description of this newly released but known for more than a year news is… colorful:

The event began with little warning when a gentle gust of solar wind delivered a bundle of magnetic fields from the Sun to Earth. Like an octopus wrapping its tentacles around a big clam, solar magnetic fields draped themselves around the magnetosphere and cracked it open. The cracking was accomplished by means of a process called “magnetic reconnection.” High above the Earth’s poles, solar and terrestrial magnetic fields linked up (reconnected) to form conduits for solar wind. Conduits over the Arctic and Antarctic quickly expanded; within minutes they overlapped over Earth’s equator to create the biggest magnetic breach ever recorded by Earth-orbiting spacecraft.

Worse, what’s going on bears little to no resemblance to sciences theories about such things. In fact, what’s happening is completely opposite to predictions!

Bottom line for our ‘interesting times’? Stock up on sunscreen, back up your hard drive regularly…

The years ahead could be especially lively. Raeder explains: “We’re entering Solar Cycle 24. For reasons not fully understood, CMEs in even-numbered solar cycles (like 24) tend to hit Earth with a leading edge that is magnetized north. Such a CME should open a breach and load the magnetosphere with plasma just before the storm gets underway. It’s the perfect sequence for a really big event.”

Links:
Sun does magnetic flip
Earth’s Magnetic Field is Fading Fast
A Giant Breach in Earth’s Magnetic Field