TRÜMPLER 30

OPEN CLUSTER IN  SCORPIUS 

 (Image Centred at ra 17h:57.3m  / dec -35:19)

July 2014 - Home Backyard in Martinez, Buenos Aires, Argentina

DATA

TYPE: Open Cluster

Apparent magnitude: 8.8

Image FOV: 54 x 50 arc minutes

Distance: not found

IMAGE INFORMATION

SCOPE: 8" Orion Optics UK w/TeleVue ParaCorr working at f5.75 and 1150 mm fl

CAMERA: QSI 583 WS

FILTERS: Baader LRGB, 2" IDAS LPS for all channels

SKY CONDITIONS: urban skies

EXPOSURES: LRGB (30,30,30,30) all bin 1x1

OBJECT DESCRIPTION AND IMAGE SESSION

46 arc minutes to the southern east from the center of Messier we find TR 30. A small and controversial open cluster, discovered by Swiss astronomer R.J. Trümpler (1886-1956). The cluster could be unnoticed with small telescopes; but from a dark skies and through middle to big apertures  it looks interesting and very nice. It has an irregular shape with not much star concentration. Shinning at magnitude 8.8 and classified as III 2p contains around 20 members from magnitude 10 onwards. The are still discussions if TR 30 is part of Messier 7 or if it is an independent open cluster (*)

(*) Free translation form the Book Exótico Cielo Profundo / Chapter 5, Page 84 (3rd edition) by Rodolfo Ferraiuolo and Enzo De Bernardini.