History Channel
Season 1 Episode. 1
http://www.history.com/shows/the-universe
http://en.wikipedia.org/wiki/The_Universe_%28TV_series%29
http://www.youtube.com/watch?v=1VSKipGmdAk
EXCERPTS:
Our Sun is a type of star known as Yellow Dwarf.
Within its boundaries you could fit one million earths.
It has a surface temp. of 10,000 Fahrenheit.
And generates 380 billion billion megawatts of power.
Fusion occurs when atoms are smashed together at a high rate of speed,
and literally fused. To get this to happen, conditions have to be just right.
Each Second, 5 million tons
Each second, inside the Sun, 600 million tons of hydrogen are fused into 595 million tons of helium. That five million tons of mass lost in the process is converted into energy equal to one billion megaton hydrogen bombs. Thats every second.
Earth and the other planets in the Solar System formed out of the same nod of gas that produced the Sun. In this process the Sun hoarded 995 of the mass.
The Sun's magnetic field is a tangled web because even though it's held together by gravity,
the plasma doesn't rotate evenly.
Plasma at the equator rotates once every 25 Earth days,
while plasma at the poles takes roughly 35 days to circle once.
Galileo was one the first modern scientists to observe sunspots.
SUNQUAKE (1998)
"The 1998 sunquake would have measured an 11.3 on the Richter scale.
More than one million times stronger than the 1989 earthquake that
shoo San Francisco.
Solar-Tsunami
"A flare can also kick-off a solar tsunami,
as waves of plasma in the Sun's atmosphere rock it up
at 700,000 miles per hour,
spreading around teh entire face of the star in a matter of hours.
CMEs
While sunquakes and solar tsunamis pose no danger to Earth,
the violent action of flare frequently triggers dangerous eruptions
called Coronal Mass Ejections, or CMEs.
...800-900 miles per second.
Where does this blob of superheated radioactive plasma go when it leaves the Sun?
Sometimes it sails out harmelessly into space.
Other times it may head closer to home.
Coronal Mass Ejection from the Sun are perhaps the most dangerous threat you've never heard of.
Also known as Solar Storms.
As the sunspot rotates around and begins to face directly at Earth,
that's when we really have to worry about a storm.
Fortunately, the perfect solar storm took kplace in 1859,
when the only technology vulnerable to the onslaught was the telegraph.
Since the era in which we've become dependant on high technology,
we've yet to see another perfect solar storm.
What happens is the Sun reverses the direction of its magnetic field
every eleven years.
So in 22 years it reverses and comes back to where it was.
Solar Maximum Solar Minimum
As we near the reversal every eleven years, the number os sunspots increases and there's a spike in solar activity.
WE call that period Solar Maximum, and those periods are interpersed about 5 years apart from periods we call Solar Minimum.
Just like hurricane seasons, solar maximums vary in intensity.
Some produce many more powerful storms than others.
The last solar max was in about 2001 and so the next one ought to be about
2012,
but there are different predictions.
Sun is tremendously loud place.
SUN ECLIPSE
Moon is 400 times smaller than the Sun, It is also 400 times closer to us.
This cosmic coincidence means that the two objects just happen to be the same apparent size in our sky, which allows for one to completely block out the other.
The Moon's orbit is tilted slighty about 5 degrees.
It it wasn't we would have an eclipse every month.
So instead of one every month we get a total eclipse somewhere on Earth about once every year and a half.
As the Moon slides in front of the Sun, it casts a shadow onto the Earth.
The outer part, where the shadow is fainter, is called the 'penumbra'.
If you're standing within the swath traced by the penumbra,
as it moves along teh Earth's surface,
then you'll see only a partial eclipse.
But travel to a spot within the path of the dark inner shadow,
called the 'umbra',
and you'll experience the majesty of a total eclipse.
There's another option if you can't travel to the path of tatality,
wait in one place long enough and total eclipe will pass right over your head
about once every 300 years.
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