Sirius A
Sirius A is the brighter main-sequence star in the Sirius binary system.
How big is it?
2,379,000 km across
Diameter · rounded model
A little perspective
About 1.71 times the diameter of Sun.
Sun: The Sun is the star at the centre of the Solar System.
Measurements, assumptions & sources +
Sirius A
A rounded main-sequence star model for the brighter member of Sirius.
Defined examples — our methodology
The marked diameter is calibrated. Unmeasured illustration details are representative.
Sun
Our star, modelled with the IAU nominal solar radius. “Surface” means the visible photosphere. The core is much hotter; this is not a solid surface.
IAU — nominal solar and planetary conversion constants
The marked diameter is calibrated. Unmeasured illustration details are representative.
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Why this measurement?
Why we use 2,379,000 km
For comparison, this page uses diameter. This is labelled rounded model: an explicit comparison model rather than a claim that every example has the same value.
A rounded main-sequence star model for the brighter member of Sirius.
The marked horizontal span follows the named feature; transparent margins and unmeasured details do not alter it. How calibrated comparisons work →
Recorded properties
Sirius A dimensions and measurements
| Property | Selected value | Recorded range | Basis |
|---|---|---|---|
| 2,379,000 km | Not recorded | rounded model | |
| 2.06 M☉ | Not recorded | rounded model |
Around this scale
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These links use compatible length records, ordered around the selected value.
Sources and method
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The source records and measurement method remain available for inspection.
More ways to see it
Curated comparisons
There’s always another scale
Follow your curiosity.
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