SOLAR PHENOMENA

THE NEUTRINO TEST - EVIDENCE OF NUCLEAR FUSION

Since the -rays released in the center do not travel out of the core directly, do we have a way to "see" into the center of the Sun and test our theory about H-fusion and high temperatures?   Yes:

• GONG and SOHO measurements of the resonant frequencies at which the Sun "rings".

• Our little friend the neutrino ()

NEUTRINO FACTS

• Remember that because they have no charge and are essentially massless, neutrinos have a very tiny "cross-section" for interacting with everything. So they pretty much pass right through the sun and even solid objects like the earth or your body. Since neutrinos pass right through the Sun and everything else, they give a direct view of what goes on in the center of the Sun for people with neutrino sensitive eyes.

• The Sun produces around 10³⁸ per second.
  All day (and night) about 1000 billion per second pass through your body!

THE GREAT MISSING NEUTRINO MYSTERY

• Starting about 30 years agos scientists decided to search for solar .
  But if neutrinos pass through essentially everything, how do you detect them?
  1. Fill up a giant swimming pool in an old gold mine with cleaning fluid.

  2. Wait for the 1 out of 10¹⁶ solar neutrinos expected to interact with a chlorine atom and become an argon atom.

  3. Drain the swimming pool and count the argon atoms.

  The answer? Too few solar neutrinos by about a factor of 2!
  Our models of how the sun should work predicted that twice as many neutrinos should be produced and detected.

• After many additional experiments and other tests of the "Standard Solar Model" it looks like what we get from this test is something new about neutrino physics since the stellar models look OK.

THE SOLAR WIND

• There is one last solar phenomenon that will be mentioned. The Solar Wind.

  Hot particles, mostly p⁺ and e^- "evaporate" from the Sun and stream into the solar system to the tune of: 1 million tons / day.

  These very high speed, charged particles are dangerous!

• Fortunately, we are protected from this radiation by the Earth's magnetic field. Because of the complex way that moving charged particles and magnetic fields interact, the charged particles from the Sun are trapped in the Van Allen Radiation belts and funneled to the North and South Poles of the Earth. There they crash into atoms in the upper atmosphere which they excite and ionize. Upon de-excitation of the atoms, photons are given off - these are the Northern and Southern Lights.

• Solar activity is variable and has some significant effects on radio communications, the lifetime of satellite orbits and apparently on the Earth's weather.