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Bortle scale

The Bortle dark-sky scale (usually referred to as simply the Bortle scale) is a nine-level numeric scale that measures the night sky's brightness of a particular location. It characterizes the observability of celestial objects, taking into account the interference caused by light pollution. Amateur astronomer John E. Bortle created the scale and…

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Overview

Scale

Reception

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Map overview Semantic statistics

Bortle scale

Nodes26
Edges25
Triples26
Avg. degree1.92
Density0.076923
Components1

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Bortle scale

Top relations

related to Reception · 11
Bortle scale → All, Bortle, Energy, It, James Brodrick, LED, Ongoing, Some, SQM, The Bortle, US Department
related to External links · 8
Bortle scale → An, Bortle, Bortle Dark-Sky Scale, Bortle ScaleLight Pollution Map, John, Original, Sky, TelescopeDarkSky InternationalInteractive

Important terminology Word statistics

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Important terminology

bortle scale light pollution sky dark-sky objects amateur brightness classes sources nelm lighting night telescope naked-eye magnitude diffuse led darksky

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
the Milky Wayinstance ofdiffuse light sources0.80text
Messier objects are invisible to the naked eyeinstance ofdiffuse light sources0.80text
and fewer point light sources such as starsinstance ofdiffuse light sources0.80text
planets can be seeninstance ofdiffuse light sources0.80text
the zodiacal light are contrastfulinstance ofand faint diffuse light sources0.80text
brilliantinstance ofand faint diffuse light sources0.80text
M33 are more difficult to see than point light sources of the same visual magnitudeinstance ofDiffuse light sources0.80text
Bortle scalerelated to External linksOriginal0.60section
Bortle scalerelated to External linksJohn0.60section
Bortle scalerelated to External linksBortle0.60section
Bortle scalerelated to External linksSky0.60section
Bortle scalerelated to External linksTelescopeDarkSky InternationalInteractive0.60section

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