Brendan: Ph.D.!

Yesterday Brendan successfully defended his Ph.D. The title of his dissertation was “Correlated SEM, FIB, and TEM studies of Material Collected by the NASA Stardust Spacecraft”. He talked about all the cool science he’s done while studying some of the most challenging and important extraterrestrial materials in our collection. Congratulations Brendan!

Presolar Grain Database

We’ve moved the presolar grain database to a group-editable Google Sheets format in an effort to keep it up-to-date and error free. My summer student last year Drew did a great job fixing a lot of errors in the database. If any of my esteemed colleagues would like to help maintain the database please let me know!

Presolar Grain Searching

This is the type of data we look at to identify isotopically anomalous presolar grains (micrometer sized dust that formed around other stars before the Solar System’s formation).

The left image shows the ratio of oxygen-17 to oxygen-16 in a 10×10 micron region of a primitive meteorite. You can see one small grain on the left is enriched in oxygen-17 by ~2000 per mil, which means it has twice as much oxygen-17 as terrestrial matter. On the right is the plot on the left divided by the statistical uncertainty of each pixel. This shows that the oxygen-17 anomaly is indeed statistically significant, close to 20-sigma.