MIMI: Magnetospheric IMaging Instrument Steven Kapturowski
MIMI: Magnetospheric IMaging Instrument
Steven Kapturowski
What is MIMI?
s Neutral and charged particle detection system s 1st Instrument designed to image planetary
magnetospheres s Global Imaging and in-situ measurement s Determine magnetospheric structure & dynamics
The Saturn System
s Rings, moons, magnetosphere, and atmosphere are tightly coupled
s Numerous plasma sources s Weak radiation belts s Buildup of Magnetic Field Lines in front
of Moons
A bit about Magnetospheres…
s Shearing of field lines ßà current sheets
s Ions tied to field lines; “frozen-in”
The Big Questions
s Voyager I established complicated magnetospheric system, but how does it compare to Jupiter?
s How important magnetosphere-moon interaction?
s Are substorms universal? s Plasma sources?
Scientific Objectives s Determine global configuration and dynamics of magnetospheric
plasmas s Determine plasma sources s Search for and characterize magnetospheric substorms. s Determine magnetosphere-satellite-ring interactions and neutral
hydrogen, nitrogen, and water product cloud formation s Investigate effect of plasma / radiation bombardment on satellite
surfaces, rings, and atmospheres s Characterize Titan's interaction with Saturn's magnetosphere
and solar wind s Assess the Cosmic Ray Albedo (CRAND) source of energetic
charged particles in the magnetosphere. s Characterize absorption of energetic ions and electrons by
satellites and rings s Study magnetosphere-ionosphere coupling
Traceability (outside of a matrix)
s Charge exchange neutrals à Plasma images s Composition & distribution à Sources s Neutral ion mapping à Neutral cloud formation s Equatorial Orbits à Satellite-plasma interactions s Inclined Orbits à Ring images s High Energy (1.6-160 MeV) ions à CRAND source
Trajectory Design
s Earth swingby used for calibration s Swingby through Jovian current sheet s Close encounters with Saturn’s moons s Titan used for gravity assists
Instrument Architecture CHEMS
LEMMS
INCA
DPU
Charge Energy Mass Spectrometer
Ion Neutral Camera
Low-E Magnetospheric Measurements System
s 3 different detectors serviced by same electronics
s CHEMS: measures charge & composition of ~3-220 keV/e ions
s LEMMS: particle spectrometer measures 3D distribution of ion/electron fluxes
s INCA: measures ENAs and distribution, E-spectra, & crude composition of ~7-3000 keV/nuc ions
MIMI Specs s Mass: 16.00 kg s Operating Power: 14.00 W s Data Rate: 7.00 kilobits/s
Energy
Cha
rge
+
-
LEMMS
INCA
CHEMS
LEMMS
INCA
Results s Radiation belt discovered within Saturn’s rings s Stability of radiation belts within Tethys orbit s Charged water products from icy moons s Enceladus, Dione, and Titan are strong sources s Asymmetric Halo of ENAs around Titan
Sources s http://lasp.colorado.edu/%7Ehoranyi/graduate_seminar/
Magnetosphere_Imaging_MIMI.pdf s http://www.universetoday.com/40065/temporary-radiation-belt-discovered-
at-saturn/
s http://www.springerlink.com/content/mm5187372h6l7123/ s http://mapsview.engin.umich.edu/data_descriptions/MIMI_instrument.php
Questions?