Astronomy Picture of the Day

Explanation: Every living thing on planet Earth is defined by its own molecule -- what's yours? This molecule, called DNA, spans about two meters stretched out but is coiled into every cell in your body. The many copies of DNA that compose you were all copied from one single cell, and your body is continually making new copies. The above ground-breaking animated video depicts the tiny, amazing, bio-molecular machinery that makes these DNA copies. For a fee, it is now possible to find part of all of the code of the DNA molecule that defines you, but lively debates involving ethics may arise regarding whether you or anyone may own, disclose, patent, or copyright it. No one knows if DNA-like molecules will also define life that originates outside of Earth.