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Energetic particles in the jovian magnetotail
R L McNutt1, D K Haggerty, M E Hill
1Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA. ralph.mcnutt@jhuapl.edu
Science (New York, N.Y.)
|October 13, 2007
Summary
The New Horizons spacecraft explored Jupiter
Area of Science:
- Planetary Science
- Space Physics
- Astrophysics
Background:
- Jupiter possesses a powerful magnetic field interacting with the solar wind.
- This interaction forms a vast magnetotail, a crucial component of Jupiter's space environment.
- Understanding the magnetotail dynamics is key to Jupiter system's outflow processes.
Purpose of the Study:
- To investigate the structure and dynamics of Jupiter's magnetotail.
- To analyze energetic particle populations within the magnetotail.
- To identify plasma behavior and potential injection mechanisms in the distant magnetotail.
Main Methods:
- In-situ measurements by the New Horizons spacecraft.
- Traversing the entire length of Jupiter's magnetotail to over 2500 Jovian radii.
- Analysis of energetic particle velocity dispersions, anisotropies, and composition.
Main Results:
- Observed a high-temperature, multispecies energetic particle population throughout the magnetotail.
- Detected ~3-day periodic variations in the deep tail ( >500 RJ), similar to near-Jupiter observations.
- Identified signatures consistent with plasma outflow and potential magnetic reconnection events in the near-tail region (200-400 RJ).
Conclusions:
- Jupiter's magnetotail maintains coherence to at least 1655 RJ.
- Plasma streaming and injection events occur within the magnetotail.
- The magnetotail plays a significant role in channeling material out of the Jovian system.
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