And how do we know that?
Well...we think we know it.
See, DNA is too small to be viewed. 59 years ago, scientists James Watson and Francis Crick wanted to know what it looked like, and used a technique called X-ray crystallography. It shoots X-rays at an object, then the way the rays bounce is analyzed. Sort of like drawing by sonar.
That was then. This is now.
Enzo Di Fabrizio is a physics professor at Magna Graecia University in Catanzaro, Italy. He decided to try to actually photograph DNA. He and his colleagues started off by mixing some DNA with water. They placed some of the water on a slide with nanoscopic water-repellant silicon pillars. When the water evaporated, it left the DNA stretched like bridges between the pillars. They then switched on the electron microscope.
And now, for the first time in human history, I present you with an actual photograph of DNA. Enjoy.