Ultra-primitive interplanetary dust particles from the comet 26P/Grigg–Skjellerup dust stream collection

Cometary Isotopic Measurements

“…In the CP-and GSC-IDPs there are numerous localized isotopic anomalies suggesting an abundant content in presolar silicates, some of them possibly being GEMS (Messenger et al 2003(Messenger et al , 2005Busemann et al 2009;Keller and Messenger 2013, and references therein). The O isotopes are distinct in various solar system materials, and therefore provide a unique tool to trace genetic relationship between solar system reservoirs.…”

“…In the GSC-IDPs, there are sub-regions showing carbon isotopic anomalies ( 12 C-rich, δ 13 C = −280 permil), suggesting the presence of primitive organic matter, or presolar grains (Busemann et al 2009). …”

“…Some larger CP-IDPs are fragmented into several patches during impact in the collector, leading to the appellation of "cluster IDPs". It has been proposed that a large proportion (if not all) of CP-or cluster IDPs are of cometary origin (e.g., Bradley and Brownlee 1986; (Busemann et al 2009). …”

Evaluating the carbon depletion found by the Stardust mission in Comet 81P/Wild 2

“…Similarly, a high proportion of organic matter was found in all 29 particles analyzed with the Cometary and Interstellar Dust Analyzer (CIDA) mass spectrometer during the comet Wild 2 flyby (Kissel et al 2004), but most of those particles were analyzed at distances greater than 650 km to the nucleus. Interplanetary dust particles (IDPs) in the Earth's stratosphere (Brownlee et al 1993;Busemann et al 2009) also are actively collected. Cometary particles are identified either by their high velocity when entering the Earth's atmosphere (Brownlee et al 1993) or through dedicated sampling by collecting particles after a close encounter with a comet (Busemann et al 2009).…”

“…Interplanetary dust particles (IDPs) in the Earth's stratosphere (Brownlee et al 1993;Busemann et al 2009) also are actively collected. Cometary particles are identified either by their high velocity when entering the Earth's atmosphere (Brownlee et al 1993) or through dedicated sampling by collecting particles after a close encounter with a comet (Busemann et al 2009). Dust particles with a cometary origin can also be retrieved from Antarctic snow (Nittler 2010).…”