Ptolemy Cluster
E472719
The Ptolemy Cluster is a bright open star cluster in the constellation Scorpius, easily visible to the naked eye and popular with amateur astronomers.
Statements (43)
| Predicate | Object |
|---|---|
| instanceOf |
Messier object
ⓘ
NGC object ⓘ deep-sky object ⓘ open star cluster ⓘ |
| age | about 200 million years ⓘ |
| angularSize | 80 arcminutes ⓘ |
| apparentMagnitudeV | 3.3 ⓘ |
| appearsAs | large, rich star field ⓘ |
| approximateNumberOfStars |
80
ⓘ
up to 100 ⓘ |
| bestSeenFrom | southern hemisphere ⓘ |
| bestSeenInMonth | July ⓘ |
| cataloguedIn |
Messier Catalogue
NERFINISHED
ⓘ
New General Catalogue NERFINISHED ⓘ |
| containsStarType |
A-type main-sequence stars
ⓘ
B-type main-sequence stars ⓘ giant stars ⓘ |
| declination | −34° 49′ ⓘ |
| discoveredBy | Claudius Ptolemy NERFINISHED ⓘ |
| discoveryNote | described by Ptolemy as a nebulous object near the stinger of Scorpius ⓘ |
| distanceFromEarth |
about 300 parsecs
ⓘ
about 980 light-years ⓘ |
| galacticLatitude | −19.0 degrees ⓘ |
| galacticLongitude | −3.3 degrees ⓘ |
| hasColorIndexBminusV | about 0.0 ⓘ |
| hasMessierNumber | M7 NERFINISHED ⓘ |
| hasNGCNumber | NGC 6475 NERFINISHED ⓘ |
| liesIn |
Milky Way
NERFINISHED
ⓘ
Scorpius OB association NERFINISHED ⓘ |
| locatedInConstellation | Scorpius NERFINISHED ⓘ |
| locatedNear | Galactic center direction ⓘ |
| namedAfter | Claudius Ptolemy NERFINISHED ⓘ |
| observedFrom | Earth NERFINISHED ⓘ |
| observedSince | antiquity ⓘ |
| observingInstrument |
binoculars
ⓘ
small telescope ⓘ |
| otherName |
Caldwell 88
NERFINISHED
ⓘ
M7 NERFINISHED ⓘ Messier 7 NERFINISHED ⓘ NGC 6475 NERFINISHED ⓘ |
| popularWith | amateur astronomers ⓘ |
| rightAscension | 17h 53m ⓘ |
| visibleToNakedEye | true ⓘ |
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.