• Megan Reiter (Edinburgh)
• Tuesday 11 May 2021, 13:00-14:00
• ONLINE – Details to be sent by email.

If you have a question about this talk, please contact Dr Annelies Mortier.

Recent work suggests that 26Al may determine the water budget in terrestrial exoplanets as its radioactive decay dehydrates planetesimals leading to drier, rockier compositions. I will review the observed distribution of 26Al in the Galaxy and typical star-forming environments and how this affects the likelihood of 26Al enrichment during planet formation. These observations indicate that high-mass stars dominate the production of 26Al. Most stars (and thus most planets) form in high-mass star-forming regions where observed 26Al abundances are comparable to those in the early Solar System. These high abundances appear to be maintained for a few Myr, much longer than the 0.7 Myr half-life of 26Al. Regular replenishment of 26Al, especially when coupled with the small age differences that are common in high-mass star-forming complexes, may significantly increase the number of star/planet forming systems exposed to 26Al. I will argue that these observations are at odds with typical model assumptions for 26Al enrichment of the Solar System but an excellent starting point for more general models of 26Al enrichment in planet formation. In particular, the data suggest that the conditions for rocky planet formation are not rare, nor are they ubiquitous, as small regions like Taurus that lack high-mass stars to produce 26Al may be less likely to form rocky planets.

This talk is part of the Exoplanet Meetings series.