How Many Galaxies Are There?
When held up to the sky, even something as small as a grain of sand can cover several light years with its diameter. It could also encompass upwards of one hundred billion stars, as galaxies can contain anywhere from 10 million stars to one trillion stars each.
Key Facts In This Video
We can only estimate the number of galaxies inside the bubble that is the observable universe. (0:09)
To estimate the number of galaxies in the observable universe, scientists count the stars in a small sample and average the number over 360 degrees. (0:22)
There is a rough estimate of as many as 500 billion galaxies in the observable universe. (1:06)