MO HB1273

Repeals section 643.020 of Missouri law and creates two new sections (643.020 and 643.630) relating to light pollution control.

Adds "light" to the definition of "air contaminant" in Missouri's air quality regulations.

Creates the "Night Sky Protection Act" requiring the Air Conservation Commission to develop voluntary guidelines to reduce night sky luminance at Missouri protected places, including state parks, wilderness areas, national wildlife refuges, scenic riverways, and military training areas.

Establishes specific luminance reduction targets: by 2025, no protected place shall exceed twice natural nighttime sky luminance; by 2025, 90% shall not exceed 30% of natural luminance; by 2040, 90% shall not exceed 20%; and by 2055, 90% shall not exceed 10% of natural luminance.

Requires the commission to develop forecasts of night sky luminance over one, five, and ten year periods and annually report luminance measurements in microcandela per square meter to the Department of Natural Resources.