The Io Plasma Torus

Volcanoes, Atmospheres, and Volcanoes, Atmospheres, and Magnetospheres, Oh My!Magnetospheres, Oh My!

Dr. Jeff MorgenthalerDr. Jeff Morgenthaler

OutlineOutline• Scientific background

– Galilean satellites– Jovian magnetosphere– Io plasma torus (IPT)

• Observing the IPT• Relating the IPT to other facets of the

Jovian system• Time allowing: other fuzzy blobs I know and

love– Comets– The heliosphere

Scientific background: Galilean Scientific background: Galilean SatellitesSatellites

• Jupiter is one of the “original” 5 planets – Planet is Greek for “wanderer”– Mercury, Venus, Mars, Jupiter, Saturn

• First telescopic observation by Galileo in 1610– Showed mini Copernican system– Four satellites

Images: Universe, Kaufmann & Freedman

Image source: NASA/JPL

Io Europa

Ganymede Callisto

Galilean Galilean Satellite Satellite Family Family PortraitPortrait

Image source: NASA/JPL

Tidal heating of IoTidal heating of Io

Prometheus

Pillan Patera

APOD 2007 February 11, Galileo data from 1997 June 28

Io is the most volcanic body in Io is the most volcanic body in the solar systemthe solar system

Scientific background: Jovian Scientific background: Jovian MagnetosphereMagnetosphere

• Magnetic field: approximated by offset, tilted dipole

Source

Scientific background: Jovian Scientific background: Jovian MagnetosphereMagnetosphere

• Magnetosphere: where a planet’s magnetic field has more influence than the solar wind on plasma

• ~50 Rj upwind, ~100 Rj downwind

NASA/JPL

Io Plasma TorusIo Plasma Torus

NASA/JPL

Observing the Io Plasma TorusObserving the Io Plasma Torus

N.M. Schneider and J.T. Trauger (1995)

Neutral density filter

Narrow-band filter (e.g. S II])

Observing the Io Plasma Torus: Observing the Io Plasma Torus: McMath-Pierce Solar Telescope DataMcMath-Pierce Solar Telescope Data

McMath-Pierce Solar Telescope McMath-Pierce Solar Telescope Io Torus ImagerIo Torus Imager

CCD

Neutral density filter

Narrow-band filter

Guider

McMath-Pierce Solar Telescope Facility (works at night too)

Relating the IPT to other facets Relating the IPT to other facets of the Jovian systemof the Jovian system

Jovian System – Io Plasma Torus

STIS observations of Io

Example spectrum: 2002 Jan 26

Io [OI] line

Io Plasma Torus SummaryIo Plasma Torus Summary

• Torus imager for portable telescopes has been successfully deployed (Nozawa et al. 2004)

• Need to verify sky is dark enough above Holland, MI

N.M. Schneider and J.T. Trauger (1995)

Comet BasicsComet Basics

Anatomy of a comet

Ion Tail

Dust Tail

Head

Sun(106 km)

Dust (1 m)

Studying comets: remote sensingStudying comets: remote sensing

CN coma:

X-ray emission from comets and X-ray emission from comets and the solar systemthe solar system

• Solar wind• Heliosphere• Local interstellar

medium

(solar wind ion)

(cometary or interplanetary hydrogen)

Diffuse X-ray SpectrometerDiffuse X-ray Spectrometer

What used to be thought of as interstellar X-ray emission may be entirely heliospheric