Io workshop 2013

• Coordination for the EXCEED (SPRINT-A) mission

Presentations • Observations of volcanoes

– dePater (Berkeley) – deKleer (Berkeley) – Rathbun (PSI)

• Volcano modeling – Howell (Wyoming) – Davies (JPL)

• Observations of atmosphere – Hendrix (PSI) – McGrath (MSFC) – Tsang (SWRI) – Spencer (SWRI)

• Atmosphere Modeling – Goldstein (Austin)

• Torus/Plasma – Crary (LASP) – Schmidt (virginia) – Kraft (SAO) – Morgenthaler (PSI) – Schneider (LASP)

• Other participants – Aiello, Bagenal, Burger,

Degenhardt, Dols, Green, Hoey, Lopes, McDoniel, Moullet, Rugenski, Skrutskie, Steffl, Trafton, Verbiscer

http://www.boulder.swri.edu/~con/ioworkshop2013/Home.html

Hisaki – SPRINT-A - EXCEED

• Launched September 14, 2013 • Extreme-ultraviolet (EUV) imaging spectrometer • observe the Jupiter

system for ~50 min on every ~100 min orbit, for several months

• Will also monitor the Io Plasma Torus & aurora

http://www.jaxa.jp/projects/sat/sprint_a/index_e.html

Model Spectrum

• Yoshioka et al., 2012

• Based on: – e- density – Core e- temp – Hot e- T – Hot e- frac

Support Observations • Jupiter Aurora

– Haleakala (Satoh) – HST/STIS (Badman) – HST/STIS (Gerard) – NOAO Gemini (Melin) – IRTF CSHELL (Stallard) – Chandra & XMM (Kraft) – Subaru (Tao)

• Io Torus/Neutrals – McDonald (Mendillo) – McMath-Pierce (Morgenthaler) – Apache Point (Schneider) – Haleakala (Kagitani) – NOAO Kitt Peak (Badman) – Suzaku (Ezoe)

• Jupiter – SOFIA (de Pater) – HST/WFPC (de Pater) – EVLA (de Pater)

• Io volcanoes – Keck (dePater) – IRTF NSFCAM2 (Rathbun) – IRTF SPEX (de Kleer) – Gemini (de Kleer) – ALMA (de Pater) – LBT/LMIRcam (Skrutskie)

• Io (other) – HST/STIS (Roth) – IRTF TEXES (Retherford) – WIND (Cecconi) – Nancay (Zarka)

https://docs.google.com/document/d/1MJzRgIRUZLkQ6qgbZT2A0ZWyhMUAacmPCSzHwg5-kv4/edit?pli=1

HST: detailed auroral morphology • The spatial resolution of EXCEED is too low to resolve

which region of the aurora is intensified. • Imaging by HST/STIS (125-170 nm) will provide high-res

snapshots of the morphology, revealing where the energy is being deposited.

• Spatially-resolved spectra (110-170 nm) obtained from HST/STIS slit spectroscopy can be used to determine the energy of the auroral electrons (10s keV).

Kitt Peak: low-energy e- in IPT

• The S and O ion emission line intensities observed by EXCEED are sensitive to electron temperatures in the range of a few 10s of keV.

• The Kitt Peak 4 m telescope in Arizona will be used to measure the lower energy component.

• S+ and S++ emission line ratios (visible wavelengths) are good indicators of the density of electrons at ~5 eV.

• Plasma torus at S+ emission line from Schneider &Traugher, 1985.

IRTF: Monitoring Io’s volcanic activity • Large eruptions eject material into Io’s atmosphere and

may be the cause of brightening in the Io Torus • Previous large eruptions observed in eclipse

occultations and reflected sunlight.

Keck: Rarog eruption

• Detected August 15 by dePater (Berkeley)

• Type of eruption likely to put large amounts of material into atmosphere and torus

• More observations requested

Lots more on e-mail discussion and…

• International Outer Planet Watch: http://bulldog2.redlands.edu/FacultyFolder/julie_rathbun/iopw/

• Contact rathbun@psi.edu or s.badman@lancaster.ac.uk to join online google doc, calendar, and/or e-mail group