Naos (nay'-os, from the Greek ναύσ "ship", also known as Suhail Hadar or ζ Puppis), a white supergiant in the constellation of Puppis, is one of the brightest stars in the Milky Way, in terms of absolute magnitude. Visually, it is tens of thousands of times brighter than the Sun; most of its radiation is in the ultraviolet, and when this is considered, it is approximately one million times brighter.

Its spectral class is O5, making this an exceptionally bright star indeed.

It is the brightest star in Puppis, with a visual magnitude of 2.21. It is around 1,400 light years distant and has an absolute magnitude around -6.

Other meanings

• NAOS (Nasmyth Adaptive Optics System) is a system of adaptive optics used to correct atmospheric distortions of astronomical images.
• Naos is also a fortified island located in Panama Bay .
• Naos is a term used in classical architecture to refer to the inner chamber of a temple which houses an idol. In the Ptolemaic period in Ancient Egypt the NAOS referred to that which is hidden and unknown inside the inner sanctum of a temple, existing in complete darkness, meant to symbolize the state of the universe before the act of creation.