<human>:  Who was the first person to calculate the age of the universe?
<bot>: Edwin Hubble calculated that the universe is about 13.7 billion years old. This was a huge breakthrough in astronomy because it meant that the universe was much older than previously thought. Hubble made his calculations using the redshift of galaxies. He noticed that the light from distant galaxies was shifted towards the red end of the spectrum. This was because the light was moving away from us as it traveled through space.