Ptolemy's Cluster

Ptolemy's Cluster is an observing target in Sco carried by the weekly Calendar.

Why it is here: The Calendar selected Ptolemy's Cluster as one of this week’s fixed-sky observing targets.

How to find it: Establish the preserved Sco constellation figure from its labeled reference stars, then use the target’s plotted position rather than searching for an isolated star.

Stellar finder for Ptolemy's Cluster

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