There are plenty of challenges in understanding the universe, beginning with the most basic traits, such as distance. Since we can’t actually go out and measure distances between things, we have to rely on other ways of determining how far something, a star or a galaxy, is.
One simple way of knowing how far a star is, for example, is to see how bright it is, the closer it is to us the brighter it will seem.
But there are plenty of other factors involved; the bigger the star, the brighter it will seem as well. If you know the precise size of a star though and its exact makeup, you can use its brightness to measure distances.
In fact, that’s the way distances to the farthest galaxies are measured, by looking at the light from Type Ia supernovae, dubbed “standard candles.”
All Type Ia supernovae have the exact same…
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