period-luminosity relation
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How Big is the Milky Way?
How big is our galaxy, anyway? And more than that — how do we know? Consider that we can’t really take a photo like this of our galaxy. We’re inside it, and space travel has not advanced to the point…
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What are Variable Stars?
What if I told you that the “two” stars you see here are actually one and the same? This star, known as L Carinae after its location in the southern constellation Carina, is actually what we call a variable star.…
