How Do We Measure the Distance of Stars?

Hank from SciShow discusses with Phil Plait, the Bad Astronomer, about how astronomers measure the distance to stars and galaxies. They explain the concept of trigonometric parallax, which uses Earth's orbit to create a binocular effect for measuring nearby stars. For more distant stars, astronomers use techniques like comparing brightness and spectral analysis. The discussion also covers the cosmic distance ladder, a method to measure distances from nearby stars to distant galaxies. Historical context is provided, highlighting Edwin Hubble's contributions to understanding the universe's expansion.

How do astronomers measure the distance to galaxies that do not have visible stars?

What significant discovery did Edwin Hubble make regarding galaxies?

Discuss the implications of discovering that the universe is expanding.