A)Solar flares -Scientific research has shown that the phenomenon of magnetic reconnection is responsible for solar flares. Magnetic reconnection is the name given to the rearrangement of magnetic lines of force when two oppositely directed magnetic fields are brought together. This rearrangement is accompanied with a sudden release of energy stored in the original oppositely directed fields.
On the Sun, magnetic reconnection may happen on solar arcades – a series of closely occurring loops of magnetic lines of force. These lines of force quickly reconnect into a low arcade of loops leaving a helix of magnetic field unconnected to the rest of the arcade. The sudden release of energy in this reconnection causes the solar flare. The unconnected magnetic helical field and the material that it contains may violently expand outwards forming a coronal mass ejection.
This also explains why solar flares typically erupt from what are known as the active regions on the Sun where magnetic fields are much stronger on an average.
http://dailypostal.com/wp-content/uploads/2010/08/solar-flare.jpgB) Satellite solar outages occur because the Sun which is a powerful broadband microwave noise source passes directly behind the satellite when viewed from Earth and the receiver with the beam directed towards the satellite picks up both the satellite signal and the noise from the Sun.
The degree of interference caused by a satellite solar outage varies from slight signal degradation to complete loss of signal as the down link is swamped by the noise from the Sun. Parameters such as the antenna directivity can make large differences to the amount of time of the solar outage. Antennas with a very wide beamwidth could be affected for as much as half an hour, whereas antennas with higher gain and directivity levels as are more commonly used for satellite reception will be affected for much shorter periods of time. Typically only a few minutes.The effect of the solar noise causing the outage is very marked. Even at times of low solar activity, the effect is very noticeable and can result in noise levels of between 10 and 20 dB above the signals from transponders, dependent upon a host of factors.
(1) http://www.radio-electronics.com/info/satellite/solar-effects/sun-solar-outages-basics-tutorial.php
C)
Due to the large amounts of energy released in a supernova explosion, much higher temperatures are reached than stellar temperatures. These higher temperatures allow for an environment where elements up to the atomic mass of 254 are formed, californium being the heaviest known, though it is seen only as a synthetic element on earth. the maximum weight for an element fused is that of iron, reaching an isotope with an atomic mass of 56. Fusion of elements between silicon and iron occurs only in the largest of stars, which end as supernova explosions.
BIBS
(1)
URL-http://www.radio-electronics.com/info/satellite/solar-effects/sun-solar-outages-basics-tutorial.php
date updated-
Title- solar outrage
Company- radio electronics
(2)
URL-http://en.wikipedia.org/wiki/Supernova_nucleosynthesis
Date updated- 11/1/10
Title-Supernova
Company- wikipedia
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