I'm warning you now that this is going to be one of those episodes that features two things.

One, a classification system that I'm made up on the spot as I drafted my notes on the subject

and has absolutely no

bearing on any professional work in astronomy at all. And two, a very long lead-up to answering

the actual question posed in the title of this episode, What Are Blue Strangler Stars?

Because if I just give you the answer of, uh, well, blue straggler stars are main sequence

stars that are bluer and brighter than the main sequence turnoff point for a stellar cluster,

that isn't very satisfying on its own. And while that answer is pretty short and to the point,

we need to unpack it a little. And so in this case, in this episode, the journey itself becomes the destination,

and we should all just enjoy the ride. Disclamers over. Before I get to the question that drives

this episode, I need to start with another simpler one. How do you tell how old a star is?

If I just gave you a random star at the sky a beetle juice a rite gel you a graze you know that's a great star name by the way a different story you just point to it and say

how old is that star how do you know how do you even begin to answer that kind of question?

It's a difficult question because, at least at first, we have no reference points.

We have no way of measuring a stellar lifetime.

We know for certain that stars live longer than human beings.

And we know for certain that stars live longer than

the entire recorded history of humanity. Because if stellar lives were shorter than that,

we would see stars dying all over the place. Yes, I know we see stars dying in supernova,

but those are very rare events compared to the multitude of stars that we can see.

If stars had a lifetime of 100 years or a thousand years or even 10,000 years,

we would be seeing stars die left and right.

...