Picture of the comet C/2014 Q2 (Lovejoy) on 12 February 2015 from 50km south of Paris. Credits: F. Noel
Comets are frozen but sometimes, gravitational disturbance sends the comets to the sun where it gets hot and deliver gases. Passing near the sun by end of January 2015, for the first time, “We found that comet Lovejoy was releasing as much alcohol as in at least 500 bottles of wine every second during its peak activity,” said Nicolas Biver of the Paris Observatory, France. 21 different organic molecules were found including ethyl alcohol and glycolaldehyde, a simple sugar. This conforts the idea that part of organic elements that allowed life on earth comes from outside.
source : http://www.nasa.gov/feature/goddard/researchers-catch-comet-lovejoy-giving-away-alcohol