Whirlpool Galaxy

Extragalactic astronomy is the study of objects and phenomena beyond the Milky Way. Among the most observed deep-space objects is the Whirlpool Galaxy (aka Messier 51). Located 31 million light-years away in the constellation Canes Venatici, it offers a face-on view enabling astronomers to study its magnificent spiral structure comprising huge numbers of stars. Within its centre and along its swirling arms, dense clouds of gas and dust are being compressed to create clusters of new stars. Not only is the Whirlpool Galaxy a captivating sight, but it also offers researchers an unprecedented opportunity to investigate star-forming processes. 

Extragalactic design

This uniquely patinaed coin portrays a coloured representation of the Whirlpool Galaxy, encircled by the inscriptions ‘EXTRAGALACTIC’, ‘23.58 KPC | 31 MLY’ (its diameter in kiloparsecs and distance from Earth in megalight-years), and its location on the celestial sphere at coordinates ‘RA 13h 29m 53s | Dec +47° 11′ 43’. The patina evokes the mystery of deep space while the spectrum of applied colours represents the stages of star formation: red of the infrared glow of hydrogen-rich star-forming regions, blue of the vibrant young stars, and yellow of the ancient stars. Representing stars within the Galaxy’s arms, the reverse is hand-set with a pink, golden, and two white diamonds. Also included are the designer’s initials ‘NM’, The Perth Mint’s ‘P’ mintmark, and 2025 year-date.