Globular Star Cluster Messier 5 in Serpens Caput: Surprising 'Vitality' | Hubble. The globular cluster Messier 5, shown here in this NASA/European Space Agency Hubble Space Telescope image, is one of the oldest belonging to the Milky Way galaxy. The majority of its stars formed more than 12 billion years ago, but there are unexpected newcomers on the scene, adding vitality to this aging population.