What’s the difference between a globular cluster and an open cluster?

1 NGC 6624 We’ll start with globular cluster NGC 6624 located in the northwest corner of the Teapot, 0.8° southeast of mag. +2.7 Kaus Media (Delta (δ) Sagittarii). Shining with an integrated magnitude

Galaxies come in all sorts of shapes and sizes. They can be broadly classified as spiral, elliptical or irregular, but each of these still leaves plenty of scope for variety. Take, for instance, the s

Stephenson 1 is a cluster that deserves to be better known. Delta (δ) Lyrae is a very wide (10-arcminute) and bright (mag. +4.3 and + 5.6) double star with a stunning colour contrast. It’s not a true

I’m responding to an article by Pete Lawrence in the April 2025 issue, titled ‘Flora crosses the Leo Triplet’ (Big Three, in the Sky Guide), which spurred me to have a look for this minor planet. I al

1 Jul 00:00 AEST (30 Jun, 14:00 UT) 15 Jul 23:00 AEST (13:00 UT) 31 Jul 22:00 AEST (12:00 UT) The chart accurately matches the sky on the dates and times shown for Sydney, Australia. The sky is differ

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