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Far-Ultraviolet Imaging Spectroscopy of Io's Atmosphere with HST/STIS

F. L. Roesler, H. W. Moos, R. J. Oliversen, R. C. Woodward, Jr., K. D. Retherford, F. Scherb, M. A. McGrath, W. H. Smyth, P. D. Feldman, and D. F. StrobelAuthors Info & Affiliations
Science
15 Jan 1999
Vol 283, Issue 5400
pp. 353-357
DOI: 10.1126/science.283.5400.353
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Abstract

Well-resolved far-ultraviolet spectroscopic images of Oi, S i, and previously undetected H iLyman-α emission from Io were obtained with the Hubble space telescope imaging spectrograph (STIS). Detected O i and Si lines (1250 to 1500 angstroms) have bright equatorial spots (up to 2.5 kilorayleighs) that shift position with jovian magnetic field orientation; limb glow that is brighter on the hemisphere facing the jovian magnetic equator; and faint diffuse emission extending to ∼20 Io radii. All O i and Si features brightened by ∼50 percent in the last two images, concurrently with a ground-based observation of increased iogenic [O i] 6300-angstrom emission. The H iLyman-α emission, consisting of a small, ∼2-kilorayleigh patch near each pole, has a different morphology and time variation.

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We thank D. Hall for valuable assistance in planning this experiment, and J. Corliss and M. Freed for long hours spent in data reduction. We also gratefully acknowledge the cooperation and assistance of our co-workers on the STIS Instrument Development Team, and the many people at the Space Telescope Science Institute whose work made these observations possible. We thank anonymous reviewers for valuable comments on the manuscript. A portion of D.F.S.'s research was accomplished at the Observatoire de Paris-Meudon; he thanks Département de Recherche Spatiale for its hospitality. This work was supported by NASA grants NAGW-3319, NAG-4168, and NAGW-6546, and NASA contracts NAS5-30131 and NAS5-30403.
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Published In

Science
Volume 283 | Issue 5400
15 January 1999

Submission history

Received: 24 August 1998
Accepted: 10 December 1998
Published in print: 15 January 1999

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Authors

Affiliations

F. L. Roesler
F. L. Roesler, R. C. Woodward Jr., and F. Scherb are in the Physics Department, University of Wisconsin, 1150 University Avenue, Madison, WI 53706, USA. H. W. Moos, K. D. Retherford, and P. D. Feldman are in the Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA. R. J. Oliversen is in the Laboratory for Astronomy and Solar Physics, NASA–Goddard Space Flight Center, Greenbelt, MD 20771, USA. M. A. McGrath is at the Space Telescope Science Institute, Baltimore, MD 21218, USA. W. H. Smyth is with Atmospheric and Environmental Research, Cambridge, MA 02139, USA. D. F. Strobel is in the Department of Earth and Planetary Science, Johns Hopkins University, Baltimore, MD 21218, USA.
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H. W. Moos
F. L. Roesler, R. C. Woodward Jr., and F. Scherb are in the Physics Department, University of Wisconsin, 1150 University Avenue, Madison, WI 53706, USA. H. W. Moos, K. D. Retherford, and P. D. Feldman are in the Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA. R. J. Oliversen is in the Laboratory for Astronomy and Solar Physics, NASA–Goddard Space Flight Center, Greenbelt, MD 20771, USA. M. A. McGrath is at the Space Telescope Science Institute, Baltimore, MD 21218, USA. W. H. Smyth is with Atmospheric and Environmental Research, Cambridge, MA 02139, USA. D. F. Strobel is in the Department of Earth and Planetary Science, Johns Hopkins University, Baltimore, MD 21218, USA.
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R. J. Oliversen
F. L. Roesler, R. C. Woodward Jr., and F. Scherb are in the Physics Department, University of Wisconsin, 1150 University Avenue, Madison, WI 53706, USA. H. W. Moos, K. D. Retherford, and P. D. Feldman are in the Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA. R. J. Oliversen is in the Laboratory for Astronomy and Solar Physics, NASA–Goddard Space Flight Center, Greenbelt, MD 20771, USA. M. A. McGrath is at the Space Telescope Science Institute, Baltimore, MD 21218, USA. W. H. Smyth is with Atmospheric and Environmental Research, Cambridge, MA 02139, USA. D. F. Strobel is in the Department of Earth and Planetary Science, Johns Hopkins University, Baltimore, MD 21218, USA.
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R. C. Woodward, Jr.*
F. L. Roesler, R. C. Woodward Jr., and F. Scherb are in the Physics Department, University of Wisconsin, 1150 University Avenue, Madison, WI 53706, USA. H. W. Moos, K. D. Retherford, and P. D. Feldman are in the Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA. R. J. Oliversen is in the Laboratory for Astronomy and Solar Physics, NASA–Goddard Space Flight Center, Greenbelt, MD 20771, USA. M. A. McGrath is at the Space Telescope Science Institute, Baltimore, MD 21218, USA. W. H. Smyth is with Atmospheric and Environmental Research, Cambridge, MA 02139, USA. D. F. Strobel is in the Department of Earth and Planetary Science, Johns Hopkins University, Baltimore, MD 21218, USA.
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K. D. Retherford
F. L. Roesler, R. C. Woodward Jr., and F. Scherb are in the Physics Department, University of Wisconsin, 1150 University Avenue, Madison, WI 53706, USA. H. W. Moos, K. D. Retherford, and P. D. Feldman are in the Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA. R. J. Oliversen is in the Laboratory for Astronomy and Solar Physics, NASA–Goddard Space Flight Center, Greenbelt, MD 20771, USA. M. A. McGrath is at the Space Telescope Science Institute, Baltimore, MD 21218, USA. W. H. Smyth is with Atmospheric and Environmental Research, Cambridge, MA 02139, USA. D. F. Strobel is in the Department of Earth and Planetary Science, Johns Hopkins University, Baltimore, MD 21218, USA.
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F. Scherb
F. L. Roesler, R. C. Woodward Jr., and F. Scherb are in the Physics Department, University of Wisconsin, 1150 University Avenue, Madison, WI 53706, USA. H. W. Moos, K. D. Retherford, and P. D. Feldman are in the Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA. R. J. Oliversen is in the Laboratory for Astronomy and Solar Physics, NASA–Goddard Space Flight Center, Greenbelt, MD 20771, USA. M. A. McGrath is at the Space Telescope Science Institute, Baltimore, MD 21218, USA. W. H. Smyth is with Atmospheric and Environmental Research, Cambridge, MA 02139, USA. D. F. Strobel is in the Department of Earth and Planetary Science, Johns Hopkins University, Baltimore, MD 21218, USA.
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M. A. McGrath
F. L. Roesler, R. C. Woodward Jr., and F. Scherb are in the Physics Department, University of Wisconsin, 1150 University Avenue, Madison, WI 53706, USA. H. W. Moos, K. D. Retherford, and P. D. Feldman are in the Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA. R. J. Oliversen is in the Laboratory for Astronomy and Solar Physics, NASA–Goddard Space Flight Center, Greenbelt, MD 20771, USA. M. A. McGrath is at the Space Telescope Science Institute, Baltimore, MD 21218, USA. W. H. Smyth is with Atmospheric and Environmental Research, Cambridge, MA 02139, USA. D. F. Strobel is in the Department of Earth and Planetary Science, Johns Hopkins University, Baltimore, MD 21218, USA.
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W. H. Smyth
F. L. Roesler, R. C. Woodward Jr., and F. Scherb are in the Physics Department, University of Wisconsin, 1150 University Avenue, Madison, WI 53706, USA. H. W. Moos, K. D. Retherford, and P. D. Feldman are in the Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA. R. J. Oliversen is in the Laboratory for Astronomy and Solar Physics, NASA–Goddard Space Flight Center, Greenbelt, MD 20771, USA. M. A. McGrath is at the Space Telescope Science Institute, Baltimore, MD 21218, USA. W. H. Smyth is with Atmospheric and Environmental Research, Cambridge, MA 02139, USA. D. F. Strobel is in the Department of Earth and Planetary Science, Johns Hopkins University, Baltimore, MD 21218, USA.
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P. D. Feldman
F. L. Roesler, R. C. Woodward Jr., and F. Scherb are in the Physics Department, University of Wisconsin, 1150 University Avenue, Madison, WI 53706, USA. H. W. Moos, K. D. Retherford, and P. D. Feldman are in the Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA. R. J. Oliversen is in the Laboratory for Astronomy and Solar Physics, NASA–Goddard Space Flight Center, Greenbelt, MD 20771, USA. M. A. McGrath is at the Space Telescope Science Institute, Baltimore, MD 21218, USA. W. H. Smyth is with Atmospheric and Environmental Research, Cambridge, MA 02139, USA. D. F. Strobel is in the Department of Earth and Planetary Science, Johns Hopkins University, Baltimore, MD 21218, USA.
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D. F. Strobel
F. L. Roesler, R. C. Woodward Jr., and F. Scherb are in the Physics Department, University of Wisconsin, 1150 University Avenue, Madison, WI 53706, USA. H. W. Moos, K. D. Retherford, and P. D. Feldman are in the Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA. R. J. Oliversen is in the Laboratory for Astronomy and Solar Physics, NASA–Goddard Space Flight Center, Greenbelt, MD 20771, USA. M. A. McGrath is at the Space Telescope Science Institute, Baltimore, MD 21218, USA. W. H. Smyth is with Atmospheric and Environmental Research, Cambridge, MA 02139, USA. D. F. Strobel is in the Department of Earth and Planetary Science, Johns Hopkins University, Baltimore, MD 21218, USA.
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  • F. L. Roesler et al.
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Far-Ultraviolet Imaging Spectroscopy of Io's Atmosphere with HST/STIS.Science283,353-357(1999).DOI:10.1126/science.283.5400.353

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