Sirius A at closer distances
Sirius A is the bright star we see in the Sirius system. Moving it inward reveals its calculated apparent size as a pale blue-white globe. The granulation is an artistic reconstruction, not an observed surface map; no bulk spin is animated.
- 2,380,000 km
- star
What would Sirius look like inside the Solar System?
At 37,399,468 km, Sirius A spans 3.6° across your sky — about 7.0 times the width of the full Moon. Light crosses that gap in 2.1 minutes.
Well inside the orbit of Mercury. Apparent size is calculated; the consequences are not simulated.
At this distance, Earth would not survive. Enjoy the view.
How big would Sirius look from one astronomical unit?
At 149,597,871 km, Sirius A spans 54.7′ across your sky — about 1.8 times the width of the full Moon. Light crosses that gap in 8.3 minutes.
A luminous blue-white globe with synthetic pale granulation, not a photographic surface map.
How big would Sirius look from five astronomical units?
At 5 AU, Sirius A spans 10.9′ across your sky — about 0.35 times the width of the full Moon. Light crosses that gap in 41.6 minutes.
The star is crossing from resolved surface to compact point source.
How big would Sirius look from twenty-five astronomical units?
At 25 AU, Sirius A spans 2.2′ across your sky — a small fraction of the width of the full Moon. Light crosses that gap in 3.5 hours.
Sirius reads as an intense point with a tight optical fringe.
How big does Sirius actually look from Earth?
At 8.6 ly, Sirius A spans 0.01 arcseconds across your sky — a small fraction of the width of the full Moon. Light crosses that gap in 9 years.
The brightest star in the sky, at the distance that makes it so. Still a point.
What Perigee calculates and what it renders
The apparent size is calculated, but the light, colour and environmental treatment are an authored visualization. Perigee does not model heat, radiation, gravity or tides.
How Perigee calculates apparent size