Sirius, in the constellation Canis Major (the Greater Dog), is our sky's brightest star, which is visible from any part of Earth, in the northern hemisphere. Sirius in the Winter Triangle southern star. In ancient times, before the foundation of Rome, Sirius was worshipped by the Egyptians in the Nile Valley, in fact their temples were orientated so as to let its light in. The Egyptian calendar was based on the heliacal setting of Sirius which happened short before the annual Nile flooding and the spring equinox.

In Greek mythology, Orion's dog became Sirius and the Greeks associated the star with the summer heat. The name, Sirius, comes from Sirios, which means "the Sunburner."

The Crest of the Unit depicts a rope surmounted by the towered crown with rostra while, in the lower part is a burgee with two five-pointed stars bearing the name "Nave Sirio".

On the left is represented the constellation Canis Majior, whose brightest star Sirius, dear to seafarers, lends the name to the unit. On the right is the coat of arms of the Italian Navy. In the lower part of the circle is the silhouette of the ship sailing a turbulent sea, placed between the stars and the coat of arms, as to symbolize Sirio's double belonging: both to heaven and to the Italian Navy. In the upper part, is the motto of the ship: "Sidus Vigilans," (Watchful Star).

In the Italian Navy there have been three units bearing this name:

An Aldebaran class destroyer launched in 1883 from Thornycroft shipyards (London), and delivered to the King's Navy on June 19, the same year. Was condemned on March 18, 1909.

The second Sirio entered service between 1905 and 1906 as a Flotilla Destroyer deployed to the Italy/Turkey war off the African coasts seizing an Egyptian sail boat and participating to the Preveza bombing in Greece.

The third Sirio was a Spica class destroyer delivered to the King's Navy on April 24, 1936 and deployed to the Dodecanese with the 10th Flotilla. After WWII, the unit underwent renovation, was used as a school ship until October 1959, when was condemned.

The current unit Sirio was launched on May 11, 2002 at the Fincantieri di Muggiano shipyards (La Spezia), and delivered to the Italian Navy on May 30, 2003. Is the first of two high seas patrol vessels meant to patrol the sea off territorial waters and carry out anti-pollution and rescue operations.

The patroller has been designed to fulfil the concept of the "New Smaller Combatant Units" of the Comandanti class, with which they share logistics, interoperability, as well as a combat system and integrated telecommunications systems features.

After the training and platform tests, has become operative under the Forces Command for Surveillance and Coastal Defence at Augusta; carrying out Fisheries Patrol, training and anti-pollution activities.

This modern unit's technical features, modern concept of habitability and ergonomics, the specificity of duties, have arisen the interest of several foreign navies. Here extreme automation and computerization of all the platform and fighting systems, allow to carry out activities with a reduced crew, yet trained to perform the whole range of inherent operations.

Her flexibility makes her the perfect training ship for commanders and crew alike.

ITS Sirio is based at Augusta, and reports to the Comando Seconda Squadriglia Pattugliatori (COMSQUAPAT DUE), which is under the Comando Forze da Pattugliamento per la Sorveglianza e la Difesa Costiera (COMFORPAT).

Her routine duties involve fisheries patrol and command school training activities.

Main activities:

• 2005 – Anti pollution exercises; promotion activities in Istanbul and Izmir (Turkey) for the Italian industries;
• 2008 – OASIS (with Tunisia) and NAUTILUS (with Malta) anti-pollution exercises and tests;
• 2009 - AMPHEX 2009 multinational exercise in Sicily; surveillance in Syracuse during the G8;
• 2010 – NAXOS anti-pollution exercise, - Navalization of the Augusta Westland AW-139 helicopter;
• 2011 – Multinational Operation COOPERATIVE SHIELD to control illegal migration flows in the Sicily Straits; POLLEX 2011 and RAMOGEPOL-HAVEN anti-pollution exercises respectively off Syracuse and Genoa;
• 2012 – Multinational exercise ADRION LIVEX with other Adriatic nations (Slovenia, Greece, Albania, Croatia, and Montenegro);
• 2013 – Anti-pollution exercise RAMOGEPOL (Mouths of Bonifacio);
• 2013/2014 – Operation Mare Nostrum in southern Sicily.

ANTI-POLLUTION CAPACITIES

• Reduction – the units are equipped with 250 m. floating pneumatic barriers (25 ten m. modular elements). These barriers are used to hold floating pollutants to allow their mechanical removal. To each inflatable element corresponds a barrier 60 cm awash. With these dimensions and features this barriers model is fit for waves under 60 cm. Each unit is equipped with two pump-jet auxiliary boats used to tow the barriers into the water so as to enhance their performance.
• Removal of pollutants – to retrieve oily substances from the surface is used a mechanical disk oil skimmer. The units are equipped with 6 boxes for the storage of the substances collected. Total stowage capacity is 330 cu. m. Maximum load ranges between 30 and 50 cu. m. per hour, depending on type of substance, viscosity, temperature and sea conditions;
• Dispersion with chemicals – the units are also equipped with a chemical agents disperser system comprising two extensible conduits placed at either side of the bow, fitted with sprinklers. Up to 32 cu. m. of disperdent can be stored aboard;
• Analysis Laboratory – a chemical lab onboard is used for rapid analysis of pollutants retrieved from surface. The samples are collected by means of ocean drills and Niskin bottles; they are then analyzed with different reagents combined. Finally, the data collected are processed with a dedicated software. A highly specialized team onboard is in charge of the lab.