Saturn; aurora; FOC; Hubble space telescope; haze; ultraviolet SPECTROMETERS; hydrocarbon
Abstract :
[en] Near simultaneous observations of the Saturnian H-2 north ultraviolet aurora and the polar haze were made at 153 nm and 210 nm respectively with the Faint Object Camera on board the post-COSTAR Hubble Space Telescope. The auroral observations cover a complete rotation of the planet and, when co-added, they reveal the presence of an auroral emission near 80 degrees N with a brightness of about 150 kR of total H-2 emission. The maximum vertical optical depth at 210 nm is found to be located similar to 5 degrees equatorward of the auroral emission zone. The haze particles are presumably formed by hydrocarbon aerosols initiated by H2+ auroral production. In this case, the 3 x 10(^10) W of H2 emission observed with the FOG, combined with the deduced haze optical depth requires an efficiency of aerosol formation of about 7%. This result indicates that auroral production of hydrocarbon aerosols is a viable source of high-latitude haze.
Disciplines :
Physical, chemical, mathematical & earth Sciences: Multidisciplinary, general & others
Author, co-author :
Gérard, Jean-Claude ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Labo de physique atmosphérique et planétaire (LPAP)
DOLS, V.
Grodent, Denis ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Labo de physique atmosphérique et planétaire (LPAP)
WAITE, J. H.
GLADSTONE, G. R.
PRANGE, R.
Language :
English
Title :
SIMULTANEOUS OBSERVATIONS OF THE SATURNIAN AURORA AND POLAR HAZE WITH THE HST/FOC
Publication date :
1995
Journal title :
Geophysical Research Letters
ISSN :
0094-8276
eISSN :
1944-8007
Publisher :
American Geophysical Union, Washington, United States
Ben Jafflel L., Leers V., Sel B.R. (1995) Dark auroral oval on Saturn discovered in Hubble Space Telescope ultraviolet images. Science 269:951.
Broadfoot A.L. (1981) Extreme ultraviolet observations from Voyager 1 encounter with Saturn. Science 212:206.
Clarke J.T., Moos H.W., Atreya S.K., Lane A.L. (1981) IUE detection of bursts of H Lyman‐alpha from Saturn. Nature 290:226.
Gérard J.C., Grodent D., Prangé R., Waite J.H., Gladstone G.R., Dols V., Paresce F., Storrs A., Ben Jaffel L., Franke K.A. (1994) A remarkable auroral event on Jupiter observed in ultraviolet with the Hubble Space Telescope. Science 266:1675.
Gérard J.C., Singh V. (1982) A model of energetic electrons and EUV emission in the Jovian and Saturnian Atmospheres and implications. Journal of Geophysical Research 87:4525.
Karkoschka E., Tomasko M.G. (1993) Saturn's upper atmospheric hazes observed by the Hubble Space Telescope. Icarus 106:428.
Lane A.L. (1982) Photopolarimetry for Voyager 2 : preliminary results on Saturn, Titan, and the rings. Science 215:537.
Pryor W.R., Hord C.W. (1991) A study of Photopolarimeter system UV absorption data on Jupiter, Saturn, Uranus and Neptune : implications for auroral haze formation. Icarus 91:161.
Sandel B.R. (1982) Extreme ultraviolet observations from the Voyager 2 encounter with Saturn. Science 215:548.
Trafton L.M., Gérard J.C., Munhoven G., Waite J.H. (1994) High‐resolution spectra of Jupiter's northern auroral ultraviolet emission with the Hubble Space Telescope. Ap. J. 421:816.
Waite J.H., Cravens T.E., Kozyra J., Nagy A.F., Atreya S.K., Chen R.H. (1983) Electron precipitation and related aeronomy of the Jovian thermosphere and ionosphere. J. Geophys. Res. 88:6143.
West R.A., Sato M., Hart H., Lane A.L., Hord C.W., Simmons K.E., Esposito L.W., Coffeen D.L., Pomphrey R.B. (1983) Photometry and polarimetry of Saturn at 2640 and 7500 Å. J. Geophys. Res 88:8679.
West R.A., Karkoschka E., Friedson A.J., Seymour M., Baines K.H., Hammel H.B. (1995) Impact debris particles in Jupiter's stratosphere. Science 267:1296.
