Retinal Exposure to Reflected Sunlight

Author
Eric Smith, Impact Scientist
Review
Outside coalition, pending
Published
The Reflect Orbital team in clean-room suits beneath a crossed mirror rig

What a normal look at reflected sunlight does to the eye, and how we will measure it.”

Eric Smith, Impact Scientist

Eye

With the naked eye, a normal look does essentially nothing. That's what our working model says.

Essentially isn't a number. So we're writing down what we'll measure, inviting outside scientists to break the model, and committing to change the service if they find a hazard.

What we know
A normal look sits far below safety limits.
What we're testing
Optics, long looks, unusual pupils.
What we've committed to
Outside review. Change if a hazard is real.
The sun · about 0.5° The mirror · from the ground
Figure 1. Same light, a fraction of the size: the sun spans half a degree, the mirror is a point. Placeholder scale.

How Light Becomes a Hazard

Light harms the eye as a dose: brightness, image size on the retina, and time. Heat injures fast; blue light injures slowly. Both have published limits.

The eye defends itself: you blink, look away, your pupil narrows. Eclipse injuries come from staring past all of that.

Figure 2. Exposure against the limit: dose over time, log scales. The line is the published limit. Placeholder values.

The Edge Cases

Naked eye is the easy case. The work is in the cases nobody should try and someone will. The goal: a number of safe seconds we can stand behind.

Optics
An 8-inch telescope gathers about 800× the light of your pupil.
Tracking
Following it for 300 seconds.
Pupils
Dilated, medicated, or not responding.
Night eyes
Pilots and dark-adapted viewers.

Viewer

Pupil

Figure 3. Case browser: every case, including the close ones. Placeholder values.
Figure 4. Every case at once: seconds to the limit; hatched cells are past 60% of it. Placeholder values.

Who Checks Our Work

Vision scientists at Stanford and UC Berkeley will review the model, and we've asked them to be critical. We'll name them when they agree.

Every endpoint was written down before results. Each step gets a post.

Step 1. Working model
Done
Step 2. Reviewers named
About a week
Step 3. An answer
About a month
EndpointWrittenStatus
Heat dose, naked eye Sep 2026 Result in
Heat dose, with optics Sep 2026 In review
Blue light, 300 s tracked Sep 2026 In review
Unusual pupils Oct 2026 Written
Pilot glare Oct 2026 Written
Figure 5. Endpoint ledger: progress, not a press release. Placeholder endpoints and dates.

What Would Change the Service

[Draft] If a realistic case crosses the limit, we change the service before it ships.

Written before the results.

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