NGC 6809
E525476
NGC 6809 is a bright, relatively nearby globular star cluster in the constellation Sagittarius, notable for its loose structure and rich population of ancient stars.
Statements (46)
| Predicate | Object |
|---|---|
| instanceOf | globular star cluster ⓘ |
| absoluteMagnitudeV | about −7.6 ⓘ |
| age | about 12.5 billion years ⓘ |
| alsoKnownAs |
M55
NERFINISHED
ⓘ
Messier 55 NERFINISHED ⓘ |
| angularSize | 19 arcminutes ⓘ |
| apparentMagnitudeV | 6.3 ⓘ |
| belongsTo | Local Group NERFINISHED ⓘ |
| bestSeenFrom | Southern Hemisphere NERFINISHED ⓘ |
| bestViewingSeason | northern summer ⓘ |
| catalog | New General Catalogue NERFINISHED ⓘ |
| contains |
RR Lyrae variable stars
NERFINISHED
ⓘ
blue horizontal branch stars ⓘ red giant branch stars ⓘ |
| coreConcentration | low ⓘ |
| declination | −30° 58′ ⓘ |
| discoveredBy | Nicolas-Louis de Lacaille NERFINISHED ⓘ |
| discoveryYear | 1752 ⓘ |
| distanceFromEarth |
about 17,600 light-years
ⓘ
about 5.4 kiloparsecs ⓘ |
| galacticLatitude | −23.3 degrees ⓘ |
| galacticLongitude | 9.0 degrees ⓘ |
| galacticSystem | Sagittarius region of the Milky Way ⓘ |
| halfLightRadius | about 9 parsecs ⓘ |
| hasColorIndexBminusV | about 0.78 ⓘ |
| horizontalBranchMorphology | blue ⓘ |
| includedInCatalogue | Messier catalogue NERFINISHED ⓘ |
| locatedIn |
Milky Way
ⓘ
Milky Way halo NERFINISHED ⓘ |
| locatedInConstellation | Sagittarius NERFINISHED ⓘ |
| messierCatalogueNumber | 55 ⓘ |
| messierNumber | M55 NERFINISHED ⓘ |
| metallicityFeH | about −1.9 ⓘ |
| notableFor |
loose structure
ⓘ
rich population of ancient stars ⓘ |
| observationalType | non-core-collapsed globular cluster ⓘ |
| observedFrom | Cape of Good Hope NERFINISHED ⓘ |
| orbitalComponent | outer halo of the Milky Way ⓘ |
| rightAscension | 19h 40m ⓘ |
| spectralTypeDominant | G and K giants ⓘ |
| stellarPopulation |
Population II stars
ⓘ
old stars ⓘ |
| structuralConcentrationClass | XI ⓘ |
| structure | loose ⓘ |
| surfaceBrightness | low ⓘ |
| visibility | visible in binoculars under dark skies ⓘ |
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.