New Attempt at Detecting the Jovian Oscillations

✍ Scribed by B. Mosser; J.P. Maillard; D. Mékarnia

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 202 KB
• Volume: 144
• Category: Article
• ISSN: 0019-1035
• DOI: 10.1006/icar.1999.6271

✦ Synopsis

This paper reports seismic observations of Jupiter conducted in

August 1996 with the Fourier Transform Spectrometer based at the CFH telescope, used as an accelerometer. With this instrument, the jovian velocity field was measured for the first time with an absolute velocity calibration. The noise in the Fourier spectrum reaches 4 cm s -1 µHz -1/2 . A dominating source of noise, identified as due to spurious velocity signals induced by the guiding errors on the rapid rotating planet, as well as a poor window function, has precluded the possible direct identification of jovian modes. However, there is strong evidence in the data for an oscillation characteristic frequency (or large splitting) ν 0 , at 142 ± 3 µHz, which confirms a low value of this parameter. Furthermore, the measurement of this parameter with a constant value in different frequency ranges along the whole Fourier spectrum seems to indicate a very small planetary core. The modes amplitude is inferred not to exceed 0.6 m s -1 in the 1-to 3.1-mHz frequency range.