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HIP 99377 The Sun (smaller than a dot at this scale)
Surface temperature
9,730 K
Radius
799 × the Sun
Luminosity
5,152,286 × the Sun
Spectral type
WN6 (SB1)
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

HIP 99377

HIP 99377 · HD 191765

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

Distance: no reliable parallax measured Apparent magnitude 8.07

Wolf–Rayet star

Its spectral type is WN6 (SB1): a dying heavyweight blowing itself apart in fierce winds. From its measured color, its surface temperature is roughly 9,731 K (9,458 °C), an estimate computed from the catalog's color index.

How far away is it?

The catalog lists no reliable parallax for this star, so its distance is honestly unknown. It is one of many stars still awaiting a precise measurement.

How powerful is it?

Its computed luminosity is 5,152,286 times the Sun's output, a genuine searchlight (derived from its brightness and distance).

Can you see it?

At apparent magnitude 8.07, it is invisible to the naked eye, though binoculars will show it. It favors northern observers.

It varies

This is a catalogued variable star (V1769): 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.