* 1 zettameter = 1,000,000,000,000,000,000 meters (10^21 meters)
* It's equal to one sextillion meters.
To put this into perspective:
* The diameter of the Milky Way galaxy is estimated to be around 100,000 light-years. One light-year is about 9.46 trillion kilometers, which translates to about 9.46 x 10^15 meters. This means the Milky Way is roughly 0.01 Zm across.
* The observable universe is estimated to be about 93 billion light-years across. That's about 8.8 x 10^26 meters, or 880 Zm.
So, a zettameter is a truly mind-bogglingly large unit of measurement!
