EDP Sciences
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Volume 424, Number 1, September II 2004
Page(s) 331 - 337
Section Planets and planetary systems
DOI http://dx.doi.org/10.1051/0004-6361:20041149

A&A 424, 331-337 (2004)
DOI: 10.1051/0004-6361:20041149

First observation of Jupiter by XMM-Newton

G. Branduardi-Raymont1, R. F. Elsner2, G. R. Gladstone3, G. Ramsay1, P. Rodriguez4, R. Soria1 and J. H. Waite Jr.5

1  Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT, UK
    e-mail: gbr@mssl.ucl.ac.uk
2  NASA Marshall Space Flight Center, SD50, Huntsville AL 35812, USA
3  Southwest Research Institute, San Antonio, Texas 78228, USA
4  XMM-Newton SOC, Apartado 50727, Villafranca, 28080 Madrid, Spain
5  University of Michigan, Space Research Building, 2455 Hayward, Ann Arbor, Michigan 48109, USA

(Received 22 April 2004 / accepted 23 May 2004 )

We present the first X-ray observation of Jupiter by XMM-Newton. Images taken with the EPIC cameras show prominent emission, essentially all confined to the 0.2-2.0 keV band, from the planet's auroral spots; their spectra can be modelled with a combination of unresolved emission lines of highly ionised oxygen (OVII and OVIII), and a pseudo-continuum which may also be due to the superposition of many weak lines. A 2.8 $\sigma$ enhancement in the RGS spectrum at 21-22 Å (~0.57 keV) is consistent with an OVII identification. Our spectral analysis supports the hypothesis that Jupiter's auroral emissions originate from the capture and acceleration of solar wind ions in the planet's magnetosphere, followed by X-ray production by charge exchange. The X-ray flux of the North spot is modulated at Jupiter's rotation period. We do not detect evidence for the ~45 min X-ray oscillations observed by Chandra more than two years earlier. Emission from the equatorial regions of the planet's disk is also observed. Its spectrum is consistent with that of scattered solar X-rays.

Key words: planets and satellites: general -- planets and satellites: individual: Jupiter -- X-rays: general

© ESO 2004