ABOUT THE SUN
The sun is the center of the Solar System and is also
a star. It is primarily composed of Hydrogen and
Helium. The sun is not a big ball of fire. It releases
radiation from nuclear reactions. It's immense
gravity forces the fusion of hydrogen into
helium. In this case the sum of the parts does not equal
the whole. When the hydrogen fuses to helium, the
excess matter is converted to energy ( E=MC2,
Where E=Energy in Joules, M=Mass in Kilograms and
C=the speed of light squared [3 x 108 M/S]2 ).
This is the same process that fuels the Hydrogen Bomb.
The Sun produces the heat and pressure necessary to
fuse hydrogen from gravity. The hydrogen bomb
requires other methods to generate the necessary
heat and pressure.
The sun has spots. They were noticed long ago but the
belief that the Sun was perfect made most distrustful
of such observations. Sunspots have been watched and
counted since the 1600's. The Sunspot cycle (there are
other cycles as well) is 11 years. The peaks and valleys in
the Sunspot Cycle are called solar maximum and
solar minimum. The peaks correspond with considerable
solar activity. Many flares occur at maximum. These
flares can disrupt communications and overload some
electrical circuits. They can bring about intense auroral
activity. The last solar peak and attendant flare caused
auroras to be seen as far south as the bahamas. Another
interesting fact is what's called the Maunder Minimum.
This was a long period when sunspots were largely
absent. At the same time Europe experienced the 'little
ice age' when the climate grew dramatically colder. (1600's)
What lies ahead for the Sun? The sun is a quite ordinary star.
In another 5 billion years it will have exhausted it's
supply of hydrogen. The contraction of the core at this
stage produces greater pressures causing the star (Sun)
to begin fusing helium. At the same time the outer layers
of the sun will have expanded creating a 'Red Giant' star.
It's size will have expanded to the Earth's orbit. Our
home is gone. The Sun may become unstable and pulsate.
Soon it will have exhausted all sources of fuel and
with no internal heat source exerting outward pressure,
the Sun collapses. It will become a 'white dwarf'. A small
fraction of it's present size. Over several billion years
it will slowly cool and finally become a cold dark
lifeless hulk. Fear not, in a few billion years, I'm sure
we can find another place to live.
OBSERVING - NAKED EYE
Don't do it. Actually when the Sun is low in the sky and
highly reddened, it can be glimpsed briefly (I am not
endorsing this). It is possible to see a naked eye sunspot
but these are rare. A total solar eclipse is another
naked eye sight but being in the path of totality is often
OBSERVING - TELESCOPE
With a proper solar filter, sunspots can easily be
observed. A special (and expensive) hydrogen-alpha filter
allows the observance of other details like Prominences
and bright Solar Flares. Another method is the projection
method. You can hold a cardboard screen behind the
telescope eyepiece to project the Sun's image. Sunspots
can be seen this way and drawn accurately. The telescope
can be pointed at the sun by observing the telescope's
shadow on the ground, do not look through it.
Also because of the intense heat at the eyepiece, do
not use a high quality eyepiece. It may be damaged.
A Solar Prominence. It is many times larger than the earth.
Solar Prominence in ultraviolet light from Skylab.
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