The Optical Spectrum of Thiozone, S3

Damian L. KokkinMichael C. McCarthy Patrick Thaddeus

NASA and NSF

Io and sulfur rich systems

• Io, the inner most of the Galilean moons of Jupiter, is known as the most volcanically active environment in the solar system.

• As a result of this activity the atmosphere and surface of Io are known to be rich in sulfur containing molecules; to date diatomic sulfur (S2), SO and sulfur dioxide (SO2) detected and mapped in absorption and emission with a combination of satellite and ground based observations2,3,4.

• S3 and S4 have been proposed to be responsible for the optical spectrum observed of Io’s atmosphere with features in the blue-green region, but to date no high resolution optical spectra exist.

Composite image from the robotic Galileo spacecraft that orbited Jupiter from 1995 to 2003 of Io showing two different volcanic plumes.1

1. NASA/JPL

2. J. R. Spencer, K. L. Jessup, M. A. McGrath, G. E. Ballester, R. Yelle, Science, 288, 1208-1210, 2000

3. A. Moullet, Cfa SMA Science Symposium 2009

4. A. Moullet, E. Lellouch, R. Moreno, M. A. Gurwell and C. Morre, A&A, 482, 279-292, 2008

Past S3

R.I. Billmers and A.L. Smith, J. Phys. Chem. 1991, 95, 4242 B. Meyer, T. Stroyer-Hansen, AND T. V. Oommen, J. MOL. SPEC. 1972, 42, 335

The Experiment

• Discharge 1.5kV and 2.5kOhm.

• 5% H2S in Ne

• Probed via 2C-R2PI-TOFMS

The Results

S3

S2

Cu

H2S

The Results

b

c

d

e

f

g

a

h

Band Assignment

Band Wavelength (cm-1) Δλ (cm-1) Assignment

a 23052.1527  - 0

b 23404.1286 351.9759 1ν1

c 23534.6984 482.5457 1ν2

d 23754.827 702.6743 2ν1

e 23884.4788 832.3261 1ν1+1ν2

f 23998.1869 946.0342 2ν2

g 24101.0161 1048.8634 3ν1

h 24221.8082 1169.6555 2ν1+1ν2

ν1 = Symmetric bend

ν2 = Symmetric stretch

00

The Future

• Measure the mass selective spectrum of S4

in the green and red region via a discharge of S8.

• Perform observations on Io and other expected sulfur rich systems as the Rotten Egg Nebula

S8 Discharge in Ne

The Future

• Measure the mass selective spectrum of S4

in the green and red region via a discharge of S8.

• Perform observations on Io and other expected sulfur rich systems as the Rotten Egg Nebula

NASA/ESA & Valentin Bujarrabal (Observatorio Astronomico Nacional, Spain)