Oxygen Isotopic Compositions of Asteroidal Materials Returned from Itokawa by the Hayabusa Mission

Abstract

Meteorite studies suggest that each solar system object has a unique oxygen isotopic composition. Chondrites, the most primitive of meteorites, have been believed to be derived from asteroids, but oxygen isotopic compositions of asteroids themselves have not been established. We measured, using secondary ion mass spectrometry, oxygen isotopic compositions of rock particles from asteroid 25143 Itokawa returned by the Hayabusa spacecraft. Compositions of the particles are depleted in (16)O relative to terrestrial materials and indicate that Itokawa, an S-type asteroid, is one of the sources of the LL or L group of equilibrated ordinary chondrites. This is a direct oxygen-isotope link between chondrites and their parent asteroid.

Reconstruction of breastfeeding and weaning practices using stable isotope and trace element analyses: A review

“…Fortunately, advancements in analytical techniques have been continuing, which have decreased the required sample amounts and thus increased the resolution of BWP reconstruction and lessened the destructive damage to specimens. For example, laser ablation stable isotope analysis (Sponheimer et al, 2006) and secondary ion mass spectrometry (also known as "isotope microscopy": Yurimoto et al, 2011) require much smaller amount of sample for isotope analysis and has the potential to trace isotopic changes at finer resolution and in a less destructive manner. Discovery of another geochemical indicator related to BWPs would also benefit the discussion of the various aspects of BWPs.…”

Hayabusa2: Scientific importance of samples returned from C-type near-Earth asteroid (162173) 1999 JU3

“…Required specification for sampler Recent developments of analytical techniques have enabled us to analyze smaller amounts of the samples as in the case of Itokawa samples Yurimoto et al, 2011;Ebihara et al, 2011;Tsuchiyama et al, 2011;Nakamura et al, 2012) and the required amount is expected to be further reduced by the 2020s. However, in order to obtain typical and/or average features of 1999 JU 3 , at least 100 mg of surface samples, including several mm-sized particles, are required for analysis to attain the scientific goals listed in Table 3.…”

“…The first asteroidal returned samples directly linked S-type asteroids and ordinary chondrites, which are the most common meteorites recovered on the Earth Yurimoto et al, 2011). The particles also showed that the asteroid was originally larger than 20 km in diameter, its interior was heated up to 800°C, and the asteroid was destroyed and re-accreted to form the present rubble pile asteroid form of Itokawa .…”

Mineralogy and noble gas isotopes of micrometeorites collected from Antarctic snow

“…Asteroidal materials occurring as meteorites have been studied in detail. In particular, those recovered from the asteroid Itokawa by the Hayabusa spacecraft have been subjected to comprehensive studies (e.g., Nakamura et al 2011;Noguchi et al 2011Noguchi et al , 2014aNoguchi et al , 2014bNagao et al 2011;Tsuchiyama et al 2011;Yurimoto et al 2011;Nakamura et al 2012;Harries and Langenhorst 2014;Keller and Berger 2014;Langenhorst et al 2014;Mikouchi et al 2014;Thompson et al 2014;Takeda et al 2015). In contrast, it is difficult to obtain samples identified to be cometary in origin, with the exception of direct sampling by the Stardust mission that returned the dust samples from the short-period comet 81P/Wild 2 (Zolensky et al 2006).…”