located about 825 light years (about 253 parsecs) from Earth,
approaching at a speed of 28 km / [s]. The diameter is approximately
7 light years. The observed brightness is 4.6 M. According to various
estimates, the age of the cluster is 230 to 300 million years. M39
contains about 50-100 stars.
Under good seeng, the cluster can be seen with the naked eye. In most cases, small binoculars are enough for observation. To find it in the sky, you must first locate the brightest star of the Swan constellation – Deneb, then Rho Cygni, 4m bright, about 9 ° E , The cluster is located 3 ° N and 1/4° W of this star.
Photos (March 2019) taken in Zwardoń. A standard place for PTMA Katowice gather.
Equipment: Canon EOS 6D, Sky-Watcher 200/1000 [mm] on EQ6 Pro.
Composition: APP (4 best frames + Flat + Bias)
Processing: GIMP v2.10.14 + add-ons (Linux)
Lights: 4 x 118 [s], ISO-1600;