Betelgeuse at closer distances
Betelgeuse is a red supergiant large enough that, placed at the centre of the Solar System, its surface would reach out past the inner planets. It is the clearest answer to the question of how close a star has to come before it stops looking like a point. The answer is: much closer than you would guess, because stars are extraordinarily far away.
- 1,050,000,000 km
- 20,000 hours
- star
How big does Betelgeuse actually look from Earth?
At 548 ly, Betelgeuse spans 0.04 arcseconds across your sky — a small fraction of the width of the full Moon. Light crosses that gap in 548 years.
At its true distance Betelgeuse is one of the brightest stars in Orion, and still a point.
How big would Betelgeuse look from one light year away?
At 1 ly, Betelgeuse spans 0.01° across your sky — a small fraction of the width of the full Moon. Light crosses that gap in 1 year.
Closer than any star actually is to the Sun, and still barely a disc.
How big would Betelgeuse look from a tenth of a light year?
At 0.1 ly, Betelgeuse spans 0.06° across your sky — about 0.12 times the width of the full Moon. Light crosses that gap in 36.5 days.
The point finally opens into something with a measurable width.
How big would Betelgeuse look from a hundredth of a light year?
At 0.01 ly, Betelgeuse spans 0.6° across your sky — about 1.2 times the width of the full Moon. Light crosses that gap in 3.7 days.
Comparable to a pass through the Oort cloud.
What would Betelgeuse look like inside the Solar System?
At 63 AU, Betelgeuse spans 6.4° across your sky — about 12 times the width of the full Moon. Light crosses that gap in 8.7 hours.
Perigee renders the apparent size and the light. It does not simulate what this would do to Earth.
At this distance, Earth would not survive. Enjoy the view.
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