Elemental compositions of comet 81P/Wild 2 samples collected by Stardust.
نویسندگان
چکیده
We measured the elemental compositions of material from 23 particles in aerogel and from residue in seven craters in aluminum foil that was collected during passage of the Stardust spacecraft through the coma of comet 81P/Wild 2. These particles are chemically heterogeneous at the largest size scale analyzed ( approximately 180 ng). The mean elemental composition of this Wild 2 material is consistent with the CI meteorite composition, which is thought to represent the bulk composition of the solar system, for the elements Mg, Si, Mn, Fe, and Ni to 35%, and for Ca and Ti to 60%. The elements Cu, Zn, and Ga appear enriched in this Wild 2 material, which suggests that the CI meteorites may not represent the solar system composition for these moderately volatile minor elements.
منابع مشابه
Variety of Organic Matter in Stardust Return Samples from Comet 81p/wild 2
Introduction: The Stardust mission captured dust particles from comet 81P/Wild 2 and returned them to Earth. Since this material has been cryogenically stored within the comet for billions of years, the Star-dust samples represent early nebular condensates and some presolar material, identified by anomalous isotopic fractionation outside the range of solar values. Carbonaceous matter has been i...
متن کاملIsotopic compositions of cometary matter returned by Stardust.
Hydrogen, carbon, nitrogen, and oxygen isotopic compositions are heterogeneous among comet 81P/Wild 2 particle fragments; however, extreme isotopic anomalies are rare, indicating that the comet is not a pristine aggregate of presolar materials. Nonterrestrial nitrogen and neon isotope ratios suggest that indigenous organic matter and highly volatile materials were successfully collected. Except...
متن کاملComment on "Organics captured from comet 81P/Wild 2 by the Stardust spacecraft".
Sandford et al. (Reports, 15 December 2006, p. 1720) reported on organic compounds captured from Comet 81P/Wild 2 by the Stardust spacecraft. We emphasize the difficulty in assigning the origin of compounds detected diffusely along particle impact tracks and show that rapid heating of aerogel that has never been exposed to cometary particle capture can generate complex aromatic molecules from l...
متن کاملInfrared spectroscopy of comet 81P/Wild 2 samples returned by Stardust.
Infrared spectra of material captured from comet 81P/Wild 2 by the Stardust spacecraft reveal indigenous aliphatic hydrocarbons similar to those in interplanetary dust particles thought to be derived from comets, but with longer chain lengths than those observed in the diffuse interstellar medium. Similarly, the Stardust samples contain abundant amorphous silicates in addition to crystalline si...
متن کاملChondrulelike objects in short-period comet 81P/Wild 2.
The Stardust spacecraft returned cometary samples that contain crystalline material, but the origin of the material is not yet well understood. We found four crystalline particles from comet 81P/Wild 2 that were apparently formed by flash-melting at a high temperature and are texturally, mineralogically, and compositionally similar to chondrules. Chondrules are submillimeter particles that domi...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Science
دوره 314 5806 شماره
صفحات -
تاریخ انتشار 2006