Abstract
Quasi‐sinusoidal density waves were frequently observed during the end of the Pioneer Venus Orbiter (PVO) mission when the orbiter was at low periapsis [Brace, this issue]. These waves occur at altitudes ∼145–155 km and have wavelengths ∼1 km. It is suggested that a radial, ambipolar electric field E0, directed downward, is established in the Venus ionosphere during electron pressure enhancements above ∼160 km. This field generates an electron E × B drift VE; the ions move radially and do not E × B drift because they are unmagnetized (i.e., νin » Ωi). This drift is shown to drive a collisional drift wave instability for sufficiently large values of VE, nominally, VE > υi where υi is the ion thermal velocity. For parameters typical of the nightside Venus ionosphere, this instability generates plasma fluctuations with wavelengths ∼1 km, consistent with observations.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
