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Naos The Sun
Surface temperature
15,520 K
Radius
16 × the Sun
Luminosity
12,555 × the Sun
Spectral type
O5IAf
Diagram, not a photograph. Colour from the star’s measured colour index; size from its luminosity and temperature, drawn to one scale with the Sun. Source: HYG stellar database.

Cataloged star · Database record + computed analysis

Naos

Designation: Zet Pup · HIP 39429 · HD 66811

A real star from the HYG catalog in the constellation Puppis.

1,083.6 light-years away Apparent magnitude 2.21

O-type: blue scorcher

Its spectral type is O5IAf: among the hottest, rarest, shortest-lived stars: surfaces above 30,000 °C, lifetimes of mere millions of years, destined for supernovae. From its measured color, its surface temperature is roughly 15,515 K (15,242 °C), an estimate computed from the catalog's color index.

How far away is it?

It lies about 1,084 light-years away (332.2 parsecs, from its measured parallax). The light reaching Earth tonight left it around the year 942.

How powerful is it?

Its computed luminosity is 12,555 times the Sun's output, a genuine searchlight (derived from its brightness and distance).

Can you see it?

At apparent magnitude 2.21, it is an easy naked-eye star under any reasonable sky. It favors southern observers.

It varies

This is a catalogued variable star (Zet): its brightness measurably changes over time, whether by pulsation, eclipses in a double system, or surface activity.

Everything above is computed from the catalog’s measured values for this star. Where a value is missing, the statement is omitted rather than guessed.

About this record

Data: the HYG stellar database v4.1 (Hipparcos + Yale + Gliese, CC BY-SA, © David Nash / astronexus). Want the full stories? Our deep star guides cover Sirius, Betelgeuse, Proxima Centauri, Vega and three dozen more. You can also browse the catalog or learn how stars live and die.