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23 Peg The Sun
Surface temperature
10,770 K
Radius
2.08 × the Sun
Luminosity
52.2 × the Sun
Spectral type
B9Vn
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

23 Peg

HIP 109056 · HD 209833

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

347.0 light-years away Apparent magnitude 5.69

B-type: blue-white powerhouse

Its spectral type is B9Vn: hot (10,000–30,000 °C), luminous and fast-burning: the searchlights of young star regions. From its measured color, its surface temperature is roughly 10,766 K (10,493 °C), an estimate computed from the catalog's color index.

How far away is it?

It lies about 347 light-years away (106.4 parsecs, from its measured parallax). The light reaching Earth tonight left it around the year 1,679.

How powerful is it?

Its computed luminosity is about 52.2 times the Sun's output (derived from its brightness and distance).

Can you see it?

At apparent magnitude 5.69, it is a naked-eye star under dark skies, washed out by city lights. It is visible from both hemispheres.

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.