Thanks for pointing this out - we didn't know about this case and it's cool to see Cortex can answer it correctly! For data sources right now, we use Wikipedia

Thanks for pointing this out - we didn't know about this case and it's cool to see Cortex can answer it correctly! For data sources right now, we use Wikipedia for Cortex but we're planning to add additional ones soon to handle more questions (e.g. questions around movies, restaurants, etc.). There are definitely some questions (e.g. earth age) that we aren't as good at right now, but we're improving those!