The HAVOC study comprises a series of missions that would create a Venus colony in five steps: 1. * Robotic exploration into the Venusian atmosphere 2. * Crewed mission to orbit Venus for 30 days 3. * Crewed mission to Venusian atmosphere for 30 days 4. * Crewed mission to Venusian atmosphere for 1 year 5. * Long-term human presence in a floating balloon.