Contrails or some may say “chemtrails” as seen at sunset on 09/28/2010 from my parents back porch in Arlington, Mississippi.
Some believe that chemtrails are more than just condensation-trails (or contrails) left by commercial airliners. Some conspiracy theorist believe that they are actually biological or chemical agents sprayed at high altitudes by government agencies for reasons undisclosed to the general public. The US government, however vehemently denies these theories. You decide for yourself