NGC 6755

OPEN CLUSTER IN AQUILA (THE EAGLE)

(Image centered at: ra 19 h:07 m / dec + 04º 13')

CLICK THE IMAGE FOR A HIGH RESOLUTION VIEW

August - 2024, Home Backyard in Martinez, Buenos Aires, Argentina

DATA

TYPE: OPEN CLUSTER

APPARENT DIAMETER: 15 arc minutes 

APPARENT MAGNITUDE (V): 7.5

DISTANCE: 8060 light years

IMAGE INFORMATION

INSTRUMENT: 6" ORION OPTICS UK (Ultra Grade Optics) w/Sky Watcher Coma Corrector (0.9x) working at at f4.5

CAMERA: QHY 183 MONO

MOUNT: VIXEN GDPX, OAG with QHY 5II Mono

FILTERS: BAADER LRGB Set Antlia HA 3nm filter

SKY CONDITIONS: urban skies - Bortle 8

EXPOSURES: LRGB (45,45,45,45)

OBJECT DESCRIPTION AND IMAGE SESSION

NGC 6755 is an open cluster of stars in the equatorial constellation of Aquila, positioned about 3° to the east of the star Delta Aquilae. It was discovered by the Anglo-German astronomer William Herschel on July 30, 1785 and is located at a distance of 8,060 light years from the Sun. NGC 6756 lies 30′ to the northeast of NGC 6755, with the pair forming a visual double cluster. However, they probably do not form a binary cluster system since they have different ages and are too distant from each other.

This cluster has a Trumpler class of II2r with a visual magnitude of 7.5 and it spans an angular size 15′. It has an estimated age of 250 million years, based on the main sequence turnoff. A total of 71 variable stars have been detected in the field of this cluster, of which 31 are eclipsing binaries, seven are pulsating variables, and 28 are most likely irregular variable red giants.