NAIL: In the video, you mentioned that the focus of ST5's science mission is to study the magnetosphere that shields the Earth from solar storms.
Can you tell us more about the solar storms and how the magnetosphere protects our planet from them?
SLAVIN: I'd be glad to. The magnetosphere is really just the high-altitude extension of the Earth's magnetic field.
Magnetic fields are really interesting and cool, at least if you're a physicist.
They're very different from other sorts of fields, for example gravity fields or electric fields.
Those fields, the lines of force that we use to visualize these fields for gravity or electricity, they tend to form straight lines.
Magnetic fields, however, always close on themselves. It's a law of nature that we really don't understand yet, but it is a fact.
So these come out of a planet like the Earth -- in our case, they come out of the southern hemisphere --
and they arc around and form great loops that close in the north.
Now, these loops go up to an altitude of about 60,000 kilometers. This is about five times the diameter of the Earth
They're stopped at that altitude because that's where the strength of the
magnetic field is no longer able to withstand the pressure of all the charged-particle radiation that's coming off of the sun.
Fortunately, again, as you saw in the piece earlier, the Earth's magnetosphere, namely the Earth's magnetic field,
is able to shield us from most of the radiation that comes from the sun and even part of the radiation that comes out of the galaxy.
Our second layer of defense is the Earth's atmosphere itself, but between the two of these, we're usually in pretty good shape.