From Academic Kids
In astronomy, the termination shock is theorised to be a boundary marking one of the outer limits of the sun's influence. It is where the bubble of solar wind particles slows down to below supersonic speed and heats up due to collisions with the galactic interstellar medium. It is believed to be about 100 astronomical units from the Sun.
The termination shock boundary fluctuates in its distance from the sun as a result of fluctuations in solar flare activity i.e. changes in the ejections of gas and dust from the sun.
Evidence (http://www.agu.org/cgi-bin/sessionssm05?meeting=sm05&part=SH22A&maxhits=200) presented at a meeting of the American Geophysical Union in May 2005 by Dr. Ed Stone suggests that the Voyager I spacecraft passed termination shock in December 2004 by virtue of the change in magnetic readings taken from the craft.
- Technical comments on Termination shock (http://www.physics.usyd.edu.au/~cairns/teaching/lecture20/node5.html/)
- Paper on the Heliosphere including comments on termination shock (http://web.mit.edu/afs/athena.mit.edu/org/s/space/www/helio.review/axford.suess.html#Distance/)
- The Heliospheric Termination Shock Structure (http://www.igpp.ucr.edu/Termination_shock.htm)de:Termination Shock