Wednesday, August 18, 2010
What happens in Vegas stays in Vegas.
But what happens on the sun doesn't stay on the sun.
As I pointed out last year:
It is known that intense solar activity can destroy ozone in the Earth's atmosphere, thus affecting climactic temperatures. See this, this, this, this and this. Indeed, the effects of solar energy on ozone may be one of the main ways in which the sun influences Earth's climate.
The sun itself also affects the Earth more than previously understood. For example, according to the European Space Agency:
Scientists ... have proven that sounds generated deep inside the Sun cause the Earth to shake and vibrate in sympathy. They have found that Earth’s magnetic field, atmosphere and terrestrial systems, all take part in this cosmic sing-along.
And NASA has just discovered that "space weather" causes "spacequakes" on Earth:
Researchers using NASA's fleet of five THEMIS spacecraft have discovered a form of space weather that packs the punch of an earthquake and plays a key role in sparking bright Northern Lights. They call it "the spacequake."
A spacequake is a temblor in Earth's magnetic field. It is felt most strongly in Earth orbit, but is not exclusive to space. The effects can reach all the way down to the surface of Earth itself.
"Magnetic reverberations have been detected at ground stations all around the globe, much like seismic detectors measure a large earthquake," says THEMIS principal investigator Vassilis Angelopoulos of UCLA.It's an apt analogy because "the total energy in a spacequake can rival that of a magnitude 5 or 6 earthquake," according to Evgeny Panov of the Space Research Institute in Austria.
"Now we know," says THEMIS project scientist David Sibeck of the Goddard Space Flight Center. "Plasma jets trigger spacequakes."
According to THEMIS, the jets crash into the geomagnetic field some 30,000 km above Earth's equator. The impact sets off a rebounding process, in which the incoming plasma actually bounces up and down on the reverberating magnetic field. Researchers call it "repetitive flow rebuffing." It's akin to a tennis ball bouncing up and down on a carpeted floor. The first bounce is a big one, followed by bounces of decreasing amplitude as energy is dissipated in the carpet.
"When plasma jets hit the inner magnetosphere, vortices with opposite sense of rotation appear and reappear on either side of the plasma jet," explains Rumi Nakamura of the Space Research Institute in Austria, a co-author of the study. "We believe the vortices can generate substantial electrical currents in the near-Earth environment."
Acting together, vortices and spacequakes could have a noticeable effect on Earth. The tails of vortices may funnel particles into Earth's atmosphere, sparking auroras and making waves of ionization that disturb radio communications and GPS. By tugging on surface magnetic fields, spacequakes generate currents in the very ground we walk on. Ground current surges can have profound consequences, in extreme cases bringing down power grids over a wide area.
What does this mean?
Some allege that spacequakes cause actual, physical earthquakes on Earth. I have no idea whether or not that is true.
The above-quoted NASA article concludes with a poem which implies such a connection:
a magnitude six
However, the poem may use artistic license rather than scientific rigor.
What is certain is that the science of the affect of space events on Earth is in its infancy, and that there are many fascinating discoveries in our future.