Japanese icebreaker Shirase (AGB-5003)

Shirase (しらせ) (Hull number: AGB-5003) is a Japanese icebreaker operated by the Japan Maritime Self-Defense Force and Japan's fourth icebreaker for Antarctic expeditions. Her predecessor (AGB-5002) had the same name.

She was launched in April 2008 and commissioned in May 2009. She began her first voyage on 10 November 2009 (Japan Standard Time).

Naming
In Japanese, the name "Shirase" is written in hiragana. Due to a JMSDF internal naming rule, an icebreaker must take its name from a place. Accordingly, the Shirase is said to take its name from Shirase Glacier. This glacier bears the family name of Lieutenant Nobu Shirase, a Japanese pioneer of Antarctic exploration.

Operations
In February 2013, anti-whaling group Sea Shepherd Conservation Society claimed the Shirase was sent to monitor its interference with the Japanese cetacean research fleet. However, according to the National Institute of Polar Research, the icebreaker was in fact far to the west off the coast of Antarctica near the Showa Base, at the time. The Japanese Government subsequently confirmed that the vessel was not involved in any operation related to the whaling program, and that Sea Shepherd's claims were "completely fake".