This is a timeline of space exploration which includes notable missions, achievements, first accomplishments and milestones in humanity's exploration of outer space. This timeline generally does not distinguish achievements by a specific country or private company, as it considers humanity as a whole. See otherwise the timeline of private spaceflight or look for achievements by each space agency. Pre-20th century 1900–1956 1957–1959 1960–1969 1970–1979 1980–1989 1990–1999 2000–2009...