Plasma observations near jupiter: initial results from voyager 2

Area of Science:

• Planetary Science
• Space Physics
• Plasma Physics

Background:

• Voyager 2's inbound pass provided crucial data on Jupiter's magnetosphere.
• Previous observations by Voyager 1 established baseline plasma characteristics.

Purpose of the Study:

• To detail Voyager 2's magnetosphere crossings and plasma observations.
• To analyze plasma behavior, composition, and structure within Jupiter's magnetosphere.

Main Methods:

• In-situ measurements of plasma density, intensity, and composition by Voyager 2.
• Analysis of planetary spin modulation to infer plasma sheet geometry.

Main Results:

• Multiple bow shock crossings and magnetospheric entry at specific Jupiter radii.
• Plasma exhibited corotation; densities and intensities comparable to Voyager 1.
• Magnetospheric plasma dominated by heavy ions (mass density ratio ~100:1).
• Observed plasma intensity dropouts near Ganymede, suggesting complex interactions.
• Plasma sheet centered on dipole equator initially, deviating towards rotational equator with distance.
• Plasma sheet's longitudinal position lagged behind the rotating dipole.

Conclusions:

• Voyager 2's data confirm and expand upon previous findings about Jupiter's magnetosphere.
• The magnetosphere's structure and dynamics are influenced by heavy ions and interactions with moons like Ganymede.
• The plasma sheet's complex geometry and behavior provide insights into Jovian magnetospheric processes.