Itokawa Asteroid

Anny Chantal Levasseur-Regourd (1)

1 PLANETO - LATMOS

Itokawa (25143) is a near-Earth stony (S-type) asteroid. This object has been the first asteroidal target for a sample return mission, the JAXA Hayabusa mission. Itokawa is likely a contact binary. It is small (major axes 530 m, 290 m, and 210 m) and has a rotation period of about 12.13 h. Its density is rather low (≈ 1950 kg m-3), meaning that it is porous. This asteroid could indeed have been built from loose-packed rocks held together by gravity, after an impact on a larger parent body. It presents a significant topographic diversity, with boulders on rough terrains and a featureless central area of fine dust particles forming a smooth regolith in gravitational lows. Such results are of importance when considering orbital deflection techniques to be implemented if a similar asteroid was discovered on a collision course with the Earth. Samples analyses have identified more than 1000 dust particles retrieved from Itokawa, with sizes mostly below 100...

Domains: Earth and Planetary Astrophysics [astro-ph.EP]

Anny Chantal Levasseur-Regourd. Itokawa Asteroid. Encyclopedia of Astrobiology, Springer Berlin Heidelberg, 2022, 978-3-642-27833-4. ⟨10.1007/978-3-642-27833-4_4029-4⟩. ⟨insu-03475931⟩