William Atkins
Saturday, 25 April 2009 18:52
Science -
Space
Page 1 of 2
The THEMIS discovery changes how scientists think about charged solar particles (plasma) from the Sun interacting with the magnetic field (magnetosphere) of the Earth. They can now more accurately measure the amount of energy released, which causes magnetic storms and intensifies auroras.
In fact,
Vassilis Angelopoulos (University of California, Los Angeles), the principal investigator for the THEMIS mission, stated,
“The discovery overturns a long-standing belief about how and when most of the solar particles penetrate Earth's magnetic field, and could be used to predict when solar storms will be severe. Based on these results, we expect more severe storms during the upcoming solar cycle.”
The maximum solar activity within the upcoming solar cycle is predicted to occur around 2012. Scientists are now predicting very severe solar storms at this time.
THEMIS, which stands for “Time History of Events and Macroscale Interactions during Substorms,” are a set of five NASA satellites that study energy released from the Earth’s magnetosphere.
When these energy bursts within the solar wind are very intense, solar storms (“substorms”) are produced, which produce brightly visible auroras in and around the North and South Polar regions of Earth. They also disrupt our communications systems on and above Earth.
According to the NASA article
Sun Often "Tears Out A Wall" In Earth's Solar Storm Shield,
“It had been thought that when the sun’s magnetic field is aligned with that of the Earth, the door is shut and that few if any solar particles enter Earth’s magnetic shield. The door was thought to open up when the solar magnetic field direction points opposite to Earth’s field, leading to more solar particles inside the shield.”
However, measurements by the THEMIS satellites find that this belief by scientists is not true.
In fact,
Marit Øieroset (University of California, Berkeley), along with colleagues, published a paper in May 2008 within the journal
Geophysical Research Letters that counters this belief.
Find out what they discovered on page two.
