C89
NGC 6087
Properties
Position & Identifiers
Visibility
Set a location in User Settings to see visibility data.
Survey Image
Loading survey image…
About C89
Description
NGC 6087 is a bright open cluster in Norma, about 3,300 light-years away. It contains about 40 stars within 12 arcminutes, with the brightest member being the Cepheid variable star S Normae, which pulsates between magnitudes 6.1 and 6.8 over 9.75 days.
Observing Tips
A fine cluster for binoculars and small telescopes. The bright Cepheid S Normae stands out at the cluster's center. Monitoring its brightness changes over a week is a rewarding project. Best from southern locations in summer.
History
Discovered by Nicolas Louis de Lacaille in 1751 from South Africa. S Normae was discovered as a Cepheid variable by Roberts in 1895 and is one of the most accessible Cepheid variables for amateur observation.
Fun Facts
S Normae's membership in this cluster was crucial for calibrating the Cepheid period-luminosity relation, since the cluster's distance provides an independent distance measurement for the Cepheid — a key rung on the cosmic distance ladder.
Community Photos (1)
Credit: Roberto Mura. License: CC BY-SA 3.0. (Wikimedia Commons)
Skybred Mar 2, 2026