NGC 2489

OPEN CLUSTER IN PUPPIS (THE STERN DECK)

(ra: 07h 56'/ dec -30º 04')

CLICK THE IMAGE FOR A HIGH RESOLUTION VIEW

February 2026, Home Backyard in Martinez, Buenos Aires, Argentina

DATA

TYPE: Open Cluster

Visual Brightness: 7.9

APPARENT DIAMETER: 8 arc minutes

DISTANCE: 4400 light years

IMAGE INFORMATION

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

CAMERA: QHY 183 MONO

MOUNT: SKYWATCHER NEQ6, OAG with QHY 5II Mono

FILTERS:  OPTOLONG LRGB Set

SKY CONDITIONS: Urban Skies. Bortle 9

EXPOSURES: LRGB (45,45,45,45) - all channels bin 1x1

OBJECT DESCRIPTION AND IMAGE SESSION

NGC 2489 is a relative bright open star cluster in the constellation of Puppis. This open cluster was discovered by German - British William Herschel on 30 December 1785. He listed it as VII 23 and noted a descrition: "A compressed cluster of pretty large stars, considerably rich...". Years later John Herschel observed the cluster from the Cape of Good Hope (h 3107). On 22 Jan 1835 (sweep 531) he recorded its description as ""...a round, pretty compressed cluster of stars 11..13th mag; 6th or 7th class; gradually brighter in the middle, pretty rich, 7' diameter.

CONICET presented a study confirming six red giants among its members, one of them being a spectroscopic binary.

Visible in the image above NGC 2489 we have Haffner 20 with a diameter of 1.8 arc minutes and visual magnitude of 11. The bluish star is SAO 198636 shining at magnitude 4,78 and to the left we have PX Puppis shining at magnitude 6.25