The journal Science, 7th June 2013, has published a paper on a study of Comet Lovejoy as it passed through the Sun's corona in december of 2011 – see http://phys.org/print289817332.html. They found its tail wiggled as it passed through the corona. It also displayed changes in intensity, direction, persistence and magnitude, the ions in the tail inter-acting with magetism and plasma in the corona.
Comet Lovejoy is a Kreutz sun grazer and is believed to be a remnant of a once much larger comet that broke apart many years ago. They are called sun grazers as they tend to strike the Sun's corona at an angle. Some break apart and disappear – others do not. Lovejoy span around the Sun and then shot back into space. It broke up several days later. Compare this account with the www.thunderbolts.info account of Lovejoy