• Comet particles collected by the Stardust mission contain chondrules and
CAIs that formed at much higher temperatures than where the icy comet accreted
• These high-temperature objects must have formed closer to the Sun and moved out beyond the planets to the comet-forming region in the Kuiper belt
• Analyses on one of these chondrule fragments, called “Iris,” reveals its history of formation and outward transport http://www.psrd.hawaii.edu/Feb12/chondrule-Wild2.html

Chronicle of a Chondrule’s Travels–What's Jupiter
Got to Do With It?
• Oxygen isotopic composition of Iris is similar to terrestrial oxygen, confirming formation in the inner solar nebula
• Aluminum-Magnesium isotope systematics place the formation age of Iris at least 3 Myr after
CAIs
• Iris must have moved out to the comet-forming region before Jupiter could have blocked its way
• Timing implies Jupiter formed more than 3 Myr after CAIs http://www.psrd.hawaii.edu/Feb12/chondrule-Wild2.html