I know. This sounds like a plot of a 1950’s scifi movie. But it is real. From my view, our localized corner of the solar system is now different than it used to be and changes in the magnetic interactions are evident everywhere. First we have the interplanetary magnetic field that took an abrupt dive in October 2005 and has not recovered since and remains at very low level:
click for a larger image
Then we have the recent discovery that the ionosphere has dropped in altitude to unexpected and unexplained low levels.
We have a solar cycle 24 (driven by the solar magnetic dynamo) which can’t seem to get out of the starting gate, being a year late with forecasts for activity from it being revised again and again.
And finally we have this, this discovery that Earth’s magnetic field can be ripped open and our atmosphere laid bare to the solar wind, much like Mars.
Magnetism is underrated in the grand scheme of things, in my opinion. We’d do well to pay more attention to magnetic trends in our corner of the universe and what effects it has on Earthly climate. – Anthony
From NASA News (h/t to Geoff Sharp)
Dec. 16, 2008: NASA’s five THEMIS spacecraft have discovered a breach in Earth’s magnetic field ten times larger than anything previously thought to exist. Solar wind can flow in through the opening to “load up” the magnetosphere for powerful geomagnetic storms. But the breach itself is not the biggest surprise. Researchers are even more amazed at the strange and unexpected way it forms, overturning long-held ideas of space physics.
“At first I didn’t believe it,” says THEMIS project scientist David Sibeck of the Goddard Space Flight Center. “This finding fundamentally alters our understanding of the solar wind-magnetosphere interaction.”
The magnetosphere is a bubble of magnetism that surrounds Earth and protects us from solar wind. Exploring the bubble is a key goal of the THEMIS mission, launched in February 2007. The big discovery came on June 3, 2007, when the five probes serendipitously flew through the breach just as it was opening. Onboard sensors recorded a torrent of solar wind particles streaming into the magnetosphere, signaling an event of unexpected size and importance.
Right: One of the THEMIS probes exploring the space around Earth, an artist’s concept. [more]
“The opening was huge—four times wider than Earth itself,” says Wenhui Li, a space physicist at the University of New Hampshire who has been analyzing the data. Li’s colleague Jimmy Raeder, also of New Hampshire, says “1027 particles per second were flowing into the magnetosphere—that’s a 1 followed by 27 zeros. This kind of influx is an order of magnitude greater than what we thought was possible.” Read the rest of this entry »
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