A search for X-ray emission from Saturn, Uranus and Neptune
نویسندگان
چکیده
We present an analysis of X-ray observations of the trans-Jovian planets Saturn, Uranus and Neptune with the ROSAT PSPC in comparison with X-ray observations of Jupiter. For the first time a marginal X-ray detection of Saturn was found and 95% confidence upper limits for Uranus and Neptune were obtained. These upper limits show that Jupiter-like X-ray luminosities can be excluded for all three planets, while they are consistent assuming intrinsic Saturn-like X-ray luminosities. Similar X-ray production mechanisms on all trans-Jovian planets can therefore not be ruled out, and spectral shape and total luminosity observed from Saturn are consistent with thick-target bremsstrahlung caused by electron precipitation as occurring in auroral emission from the Earth.
منابع مشابه
ar X iv : a st ro - p h / 01 11 29 0 v 1 1 4 N ov 2 00 1 Submitted to AJ The formation of Uranus and Neptune among Jupiter and Saturn
The outer giant planets, Uranus and Neptune, pose a challenge to theories of planet formation. They exist in a region of the Solar System where long dynamical timescales and a low primordial density of material would have conspired to make the formation of such large bodies (∼ 15 and 17 times as massive as the Earth, respectively) very difficult. Previously, we proposed a model which addresses ...
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