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Pinwheel Galaxy

The Pinwheel Galaxy (also known as Messier 101, M101 or NGC 5457) is a face-on, counterclockwise intermediate spiral galaxy located 21 million light-years (6.4 megaparsecs) from Earth in the constellation Ursa Major. It was discovered by Pierre Méchain in 1781 and was communicated that year to Charles Messier, who verified its position for inclusion in…

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Structure and composition

Milky WayAndromeda GalaxyH II regionsStar formationSuperbubbles
13 related topics

Supernovae and luminous red nova

SupernovaeMax WolfMilton HumasonType II supernovaSN 2011fe
12 related topics

Companion galaxies

NGC 5204NGC 5474NGC 5477NGC 5585UGC 8837
7 related topics

Discovery

William HerschelLord RosseNewtonian reflectorBinoculars
4 related topics

Key facts & relationships

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Apparent magnitude (V)
7.9
Apparent size (V)
28.8′ × 26.9′
Constellation
Ursa Major
Declination
+54° 20′ 56.220″
Distance
21.6 ± 0.28 Mly (6.644 ± 0.087 Mpc)
Heliocentric radial velocity
241 ± 2 km/s

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Overview

Discovery

Structure and composition

Companion galaxies

Supernovae and luminous red nova

Advanced semantic analysis

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Map overview Semantic statistics

Pinwheel Galaxy

Nodes53
Edges52
Triples59
Avg. degree1.96
Density0.037736
Components1

How this topic connects Entity context

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Pinwheel Galaxy

Top relations

related to External links · 38
Pinwheel Galaxy → April, Articles, Astronomy Picture, Astrophoto, Astrophotography, Avet, Bonnell, Brady Haran, Constellation Guide, Day, Deep Sky Videos, Dhillon, DSS2, Galaxy, GALEX, Hydrogen, IRAS, M101, March, May
see also · 10
Pinwheel Galaxy → Coma Berenices, Face-on, Galaxy, Hydra, List, Messier, Pisces, Southern Pinwheel GalaxyMessier, Spiral, Triangulum
Apparent magnitude (V) · 1
Pinwheel Galaxy → 7.9
Apparent size (V) · 1
Pinwheel Galaxy → 28.8′ × 26.9′
Constellation · 1
Pinwheel Galaxy → Ursa Major
Declination · 1
Pinwheel Galaxy → +54° 20′ 56.220″
Distance · 1
Pinwheel Galaxy → 21.6 ± 0.28 Mly (6.644 ± 0.087 Mpc)
Heliocentric radial velocity · 1
Pinwheel Galaxy → 241 ± 2 km/s
Number of stars · 1
Pinwheel Galaxy → 1 trillion (1012)
Redshift · 1
Pinwheel Galaxy → 0.000804

Important terminology Word statistics

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Important terminology

m101 galaxy type pinwheel ii discovered messier spiral sn ngc constellation stars telescope hubble large mag february companion also diameter

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Pinwheel GalaxyApparent magnitude (V)7.91.00infobox
Pinwheel GalaxyApparent size (V)28.8′ × 26.9′1.00infobox
Pinwheel GalaxyConstellationUrsa Major1.00infobox
Pinwheel GalaxyDeclination+54° 20′ 56.220″1.00infobox
Pinwheel GalaxyDistance21.6 ± 0.28 Mly (6.644 ± 0.087 Mpc)1.00infobox
Pinwheel GalaxyHeliocentric radial velocity241 ± 2 km/s1.00infobox
Pinwheel GalaxyNumber of stars1 trillion (1012)1.00infobox
Pinwheel GalaxyRedshift0.0008041.00infobox
Pinwheel GalaxyRight ascension14h 03m 12.5441s1.00infobox
Pinwheel GalaxySize252,000 ly (77.31 kpc) (diameter; 4050 Å high surface brightness level)1.00infobox
Pinwheel GalaxyTypeSAB(rs)cd HII1.00infobox
Pinwheel Galaxyrelated to External linksSEDS0.60section

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