the.com/brightness
the slider everyone cranks down at 3am and back up by noon.
means The quality or degree to which something gives off or reflects light, from a dim glow to a blazing glare.
from Rooted in Old English 'beorht' (bright, shining, clear) — a word with cousins across the old Germanic tongues, like Gothic 'bairhts.' Tack on the noun-making suffix '-ness' (also Old English, the same one quietly working in 'darkness' and 'kindness') and you get the abstract state of being bright. The 'gh' in the modern spelling is a ghost of a throaty sound English speakers stopped pronouncing centuries ago.
- unit
- measured in nits, named from Latin for shining
- sun's output
- about 1.6 billion nits at the surface
- phone limits
- screens hit 2000+ nits to beat sunlight
- perception trick
- eyes judge brightness by contrast, not absolutes
- star scale
- magnitude runs backward, brighter means lower numbers
sirius — brightest star in earth's night sky at magnitude -1.46
venus — brightest planet visible from earth, reaching magnitude -4.67
sun — brightest object in earth's sky at magnitude -26.74