title: RETRACTED: X-ray fluorescence spectrometry of asteroid Itokawa by Hayabusa.
abstract: X-ray fluorescence spectrometry of asteroid 25143 Itokawa was performed by the x-ray spectrometer onboard Hayabusa during the first touchdown on 19 November 2005. We selected those data observed during relatively enhanced solar activity and determined average elemental mass ratios of Mg/Si = 0.78 +/- 0.09 and Al/Si = 0.07 +/- 0.03. Our preliminary results suggest that Itokawa has a composition consistent with that of ordinary chondrites, but primitive achondrites cannot be ruled out. Among ordinary chondrites, LL- or L-chondrites appear to be more likely than H-chondrites. No substantial regional difference was found on the asteroid surface, indicating its homogeneity in composition.
authors.affiliation: Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa 229-8510, Japan. okada@planeta.sci.isas.jaxa.jp
authors.forename: Tatsuaki
authors.initials: T
authors.lastname: Okada
authors.forename: Kei
authors.initials: K
authors.lastname: Shirai
authors.forename: Yukio
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Takehiko
authors.initials: T
authors.lastname: Arai
authors.forename: Kazunori
authors.initials: K
authors.lastname: Ogawa
authors.forename: Kozue
authors.initials: K
authors.lastname: Hosono
authors.forename: Manabu
authors.initials: M
authors.lastname: Kato