Star Cluster NGC 2516

This is a beautiful southern cluster of about a hundred stars, which fitted just nicely into the field of view.

Object Details:

NGC 2516, Caldwell 96.
Constellation: Carina.
Visual magnitude: +3.79
Apparent diameter: 30 arc-min. (about 1 Lunar Diameter).
Actual diameter: 11.6 light years.
Distance: 1,300 light years.
Altitude: 58° above Southern Horizon.


Exposure: 20 x 2 min, ISO 1000 (+ 6 dark, 10 bias).
Date: 2017-12-10.
Location: Leumeah
Light pollution: outer Sydney suburban.
Cloud: nil.
Moon: No.
Processing: Canon DPP > Deep Sky Stacker > GIMP.
Cropping: no.

Imaging telescope: Skywatcher Esprit 120ED Super APO triplet refractor.
Focal length: 840 mm, focal ratio: f/7.
Imaging camera: Canon EOS 60D.
Guiding camera: Orion StarShoot.
Guiding control software: PHD2.
Guiding accuracy: 0.5″ to 0.7″ rms approx.
Telescope mount: SkyWatcher EQ6-R.
Polar aligning: QHYCCD PoleMaster.
Polar aligning accuracy: 12 arc-min
Field flattener: yes; filter: no.

Observing Notes:

I spent a long time trying to align the telescope. One attempt was made at three-star alignment followed by several attempts at one-star alignment. The final accuracy was still poor but allowed me to pick this object in the 9×50 finderscope.

Image © R.Powell


Leave a comment or ask a question . . . .

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s