User:Hari maddi

Plasma Bubbles:

Ionospheric plasma bubbles associated with night time equatorial spread F phenomena (Booker and Wells, 1938) have been the subject of intense experimental and theoretical investigations during the recent years. These irregularities of different scale sizes have been observed using 1.	Ionosondes 2.	Topside Sounders. 3.	Incoherent Radar 4.	Scintillations 5.	In situ rockets 6.	Satellites 7.	Conventional Photometers(scanning and tilting) 8.	Wide angle imaging system.

According to the present theoretical interpretations, large scale plasma bubbles are initially generated at the bottom side of the F-region through a fluid type gradient instability mechanism such as G.R.T instability (Dungey,1956; Ossako et al.,1979) in conjunction with Ex B instability (Martyn, 1979).

Properties:

1.	The bubbles are aligned along the magnetic field lines, owing to their much conductivity along the field lines as compared to perpendicular direction. 2.	They generally move towards the east in the equatorial ionosphere, often tilted in the westward direction because of the bubble upward direction.