The MV Sirius is a Greenpeace ship named after the star Sirius. The Sirius was built with modern specifications at the Boele shipyard in the Netherlands in 1950 as one of 7 pilot vessels. The ship, originally owned by the Royal Dutch Navy, was sold to Greenpeace during 1981 while in dry dock. The ship was refitted, repaired, and repainted. It took ten weeks to paint her. The ship's colour scheme was soon changed to a green hull and rainbow colours and a white dove of peace with an olive branch was painted on the bow. Sirius was refitted with more modern navigation systems, communication equipment, lifeboats, and rafts. The pantries were turned into outdoor engine rooms and the mess room became a storage room.
Sirius served as the flagship of Greenpeace Netherlands through 1998, after which she was retired. She is now docked at Amsterdam, where she serves in an educational capacity, offering shipboard tours and environmental education.