Thanks, Daniel.
I am not sure whether I referred to a relevant sutta there. The following sutta describes that there are a thousand world-systems of which ours (Earth-based life) in just one. Furthermore, there are an uncountable number of such “clusters.”
“Paṭhamakosala Sutta (AN 10.29)”
– “..sahassaṁ jambudīpānaṁ sahassaṁ aparagoyānānaṁ sahassaṁ uttarakurūnaṁ sahassaṁ pubbavidehānaṁ” refer to those 4 human abodes within ours. Of course, we can see only the jambudīpā or this Earth. This also confirms that jambudīpā is NOT India or Sri Lanka. It includes all countries where humans live (those we can see).
– A reasonable translation there: “Kosala (1)”
Different Buddhas are born in different clusters. This is why the Buddha said this kind of analysis is unthinkable for average humans. See, “Acinteyya Sutta (AN 4.77)“.
– A reasonable translation there: “Unconjecturable“