It is a runaway star, meaning it has an unusually large space velocity, probably caused by being ejected from a close binary system when its companion exploded as a supernova.
[10] USS Naos (AK-105) was a United States Navy Crater class cargo ship named after the star.
Zeta Puppis has been extensively studied because of the rarity of such hot massive stars and its relative closeness to Earth, but its physical parameters and distance are still poorly known.
The enhanced Helium and Nitrogen and the lower surface gravity indicates some degree of evolution away from the zero age main sequence and Zeta Puppis is ranked as a supergiant.
The eclipse-like light curve is now thought to be due to rotation of the star which has large irregular features at the base of its dense stellar wind.
[6][18] In 1896, Williamina Fleming observed mysterious spectral lines from Zeta Puppis, which fit the Rydberg formula if half-integers were used instead of whole integers.
A distance of 800pc requires an abnormally high luminosity, while the Vela OB2 association is much older than Zeta Puppis and the space velocity does not lead back to that cluster.
A recent dynamical study points to Zeta Puppis originating in the Trumpler 10 OB association at around 300pc, but this is also a much older cluster and physical models still lead to a distance of 450-600pc.
[24] Models of binary systems are able to reproduce the properties of Zeta Puppis following mass transfer from a companion which then exploded as a supernova.