the astronomical magnitude scale.
poniższa skala jest podana jako pouczające narzędzie, aby dać ogólne pojęcie o tym, jak działa skala wielkości. Skala poniżej ma być z grubsza wizualna; wydajność wykrywania ludzkiego oka (dostosowana do ciemności) piki około 495 nanometrów, podczas gdy formalny pik fotoelektryczny V (przefiltrowane pasmo mające być zbliżone do wizualnego) wynosi około 550 nm; CCD mają tendencję do szczytowego około 700 nm., Podane przykłady nie są „dokładne”, ponieważ obiekty niebieskie są często mierzone z dokładnością lub 0,1 lub 0,01 magnitudo; na przykład Syriusz świeci przy V = -1,47 (Yale Bright Star Catalogue),a planeta Wenus zmienia jasność na ogół od magnitudo-4,5 do -3,7. Zauważ, że kometa o jasności 5 magnitudo nie będzie tak łatwa do zobaczenia jak gwiazda o jasności 5 magnitudo, ponieważ ta sama jasność, która jest skoncentrowana w punkcie Dla gwiazdy, jest rozłożona na powierzchni nieba dla komety rozproszonej o stosunkowo dużej komie.,
Magnitude Needed to see an object of this brightness* Examples -26 the sun -13 full moon -6 crescent moon -4 naked eye: easy even from large cities planet Venus -2 naked eye planet Jupiter -1 naked eye brightest star, Sirius; totally- eclipsed moon; C/1995 O1 (Hale- Bopp) near peak 0 naked eye: difficult if near bright summer evening star artificial lights but generally Vega; C/1996 B2 visible even from large cities (Hyakutake) at peak +1 naked eye: brilliant as seen from planet Saturn dark, rural areas +2 naked eye: difficult but visible from stars of Big Dipper small cities and suburbs; diffuse Halley's comet in objects such as comets may require 1986 near peak small binoculars from urban areas 3 naked eye: rural, suburban, small city faintest naked-eye binoculars: bright, urban areas stars visible from many smaller cities/inner suburbs; 4 naked eye: (outer) suburbs faintest naked-eye binoculars: cities (stars), suburban stars visible from areas (diffuse objects such as comets) many smaller cities/(outer) suburbs 5 generally binocular objects from urban moons of Jupiter and suburban areas; faintest naked-eye stars visible from "dark" rural areas located some 40 miles (60 km) from major cities 6 binocular objects from suburban areas; planet Uranus faintest naked-eye stars visible from "dark" rural areas located some 100 miles (150 km) from major cities 7 binoculars; faintest naked-eye stars brightest minor visible from "dark" rural areas planet (asteroid) located some 140 miles (200 km) from and about 1-2 major cities and some 30 miles (50 km) comets each year from nearest town of population 5000 or so 8 binocular objects; from urban areas, such planet Neptune objects may only be visible with small telescopes 10 from dark sky, objects visible with at any given 20x80 binoculars; from brighter sites, time, there are a larger telescope is needed usually a couple of comets this bright 11 general limiting visual brightness# of comets with a 15-cm-aperture reflector 12 general limiting visual brightness# of at any given time, comets with a 20-cm-aperture reflector there are usually a half dozen comets this bright 13 general limiting visual brightness# of comets with a 25-cm-aperture reflector 14 general limiting visual brightness# of Pluto at its brightest stars with a 20-cm-aperture reflector 15 general limiting visual brightness# of comets with a 50-cm-aperture reflector 19 general limiting photographic brightness# of comets with a 50-cm-aperture reflector 21 general limiting brightness of stars with a 60-cm-aperture reflector + CCD 22 general limiting brightness# of comets with a CCD and 150-cm-aperture reflector* naked-eye viewing assumes 20-20 vision (corrected or uncorrected)# from a dark, rural site; "visual" as compared to "photographic" or "CCD-detected"; "reflector" means "reflecting telescope"
ICQ