Human DNA is so long it could go to the Sun and back hundreds of times.
Why it is true
If we stretched all the DNA from a single human cell, it would be about 2 meters long. Considering the 37 trillion cells in the body, the total stretched DNA would be about 7.4 x 10^10 meters, equivalent to traveling the distance from Earth to the Sun and back more than 200 times.
Source: Genetics
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