2009 (MMIX) was a common year starting on Thursday (dominical letter D) of the Gregorian calendar, the 2009th year of the Common Era (CE) and Anno Domini (AD) designations, the 9th year of the 3rd millennium, the 9th year of the 21st century, and the 10th and last year of the 2000s decade.

2009 was designated as:

  • International Year of Astronomy[1][2]
  • International Year of Natural Fibres[3]
  • International Year of Reconciliation
  • Year of the Gorilla (UNEP and UNESCO)