Every eight minutes, gateways for particles open and close

Nov 3, 2008 12:46 GMT  ·  By

According to NASA scientists, every 8 minutes – about the time it takes one to read this article – there's a peculiar and still unexplained event going on way overhead. The magnetosphere – the protective magnetic bubble that envelops the planet, Earth's equivalent of the heliosphere – opens up, providing a direct magnetic connection with the Sun, situated 93 million miles (150 million kilometers) away. Tons of high-energy particles pass undisturbed, carried by the solar wind, through the gateway of the magnetosphere, before it is shut once again.

“It's called a flux transfer event or 'FTE',” shares David Sibeck, a space physicist from the Goddard Space Flight Center. “Ten years ago, I was pretty sure they didn't exist, but now the evidence is incontrovertible.” There's even more to just that, he indicates, as the FTE phenomenon may take place twice more often than previously accepted. The series of 4 Cluster-type spacecrafts of the European Space Agency, as well as NASA's 5 THEMIS probes, have closely and intensely studied and measured the process, while flying in close proximity of it.

They eventually demonstrated the process was real. While Earth's magnetic field presses against the Sun's, every 8 minutes they merge into a cylindrically shaped portal about the width of the Earth. “We used to think the connection was permanent and that solar wind could trickle into the near-Earth environment anytime the wind was active. We were wrong. The connections are not steady at all. They are often brief, bursty and very dynamic,” explains Sibeck.

Based on his latest calculations, he states, “I think there are two varieties of FTEs: active and passive. Passive FTEs may not be very important, but until we know more about them we can't be sure.” The active form allows for an easier access of the particles, while the passive one induces more resistance. Done: the FTE that has possibly begun when you started reading this has now ended.