title: Touchdown of the Hayabusa spacecraft at the Muses Sea on Itokawa.
abstract: After global observations of asteroid 25143 Itokawa by the Hayabusa spacecraft, we selected the smooth terrain of the Muses Sea for two touchdowns carried out on 19 and 25 November 2005 UTC for the first asteroid sample collection with an impact sampling mechanism. Here, we report initial findings about geological features, surface condition, regolith grain size, compositional variation, and constraints on the physical properties of this site by using both scientific and housekeeping data during the descent sequence of the first touchdown. Close-up images revealed the first touchdown site as a regolith field densely filled with size-sorted, millimeter- to centimeter-sized grains.
authors.affiliation: Department of Planetary Science, Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510 Japan. yano@isas.jaxa.jp
authors.forename: Hajime
authors.initials: H
authors.lastname: Yano
authors.forename: T
authors.initials: T
authors.lastname: Kubota
authors.forename: H
authors.initials: H
authors.lastname: Miyamoto
authors.forename: T
authors.initials: T
authors.lastname: Okada
authors.forename: D
authors.initials: D
authors.lastname: Scheeres
authors.forename: Y
authors.initials: Y
authors.lastname: Takagi
authors.forename: K
authors.initials: K
authors.lastname: Yoshida
authors.forename: M
authors.initials: M
authors.lastname: Abe
authors.forename: S
authors.initials: S
authors.lastname: Abe
authors.forename: O
authors.initials: O
authors.lastname: Barnouin-Jha
authors.forename: A
authors.initials: A
authors.lastname: Fujiwara
authors.forename: S
authors.initials: S
authors.lastname: Hasegawa
authors.forename: T
authors.initials: T
authors.lastname: Hashimoto
authors.forename: M
authors.initials: M
authors.lastname: Ishiguro
authors.forename: M
authors.initials: M
authors.lastname: Kato
authors.forename: J
authors.initials: J
authors.lastname: Kawaguchi
authors.forename: T
authors.initials: T
authors.lastname: Mukai
authors.forename: J
authors.initials: J
authors.lastname: Saito
authors.forename: S
authors.initials: S
authors.lastname: Sasaki
authors.forename: M
authors.initials: M
authors.lastname: Yoshikawa