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OATS-DAUT SEMINAR
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Speaker: Marco Fulle (INAF-OATs)

Title: Iron tails

Date: Wednesday, January 9th, 2008
Time: 12:00
Venue: Villa Bazzoni

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Abstract:
In January 2007, at the heliocentric distance r < 0.3 Astronomical Units, comet McNaught 2006P1 became the brightest comet since C/Ikeya-Seki 1965S1 and was continuously monitored by space-based solar observatories. An arch-like tail observed by the Heliospheric Imager aboard the STEREO spacecraft is the first ever detected tail composed of neutral Fe atoms, providing the first estimate of the Fe lifetime, which results in 4.1 ± 0.4 10⁴ s at r = 0.25 AU, in agreement with theoretical predictions of photo-ionization lifetime. The expected dust temperature is inconsistent with iron sublimation, suggesting that Fe atoms are coming from troilite evaporation, in agreement with Stardust samples which contain most iron in such sulfides.
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contact: Marco Fulle (OATS)