BV photometry of a possible open star cluster pair NGC 7031/NGC 7086

TL;DR

This study uses CCD BV photometry to analyze two nearby open star clusters, NGC 7031 and NGC 7086, determining their ages and distances to assess if they form a true binary cluster, concluding they do not.

Contribution

The paper provides new photometric measurements and age-distance analysis to evaluate the binary nature of NGC 7031 and NGC 7086, clarifying their relationship.

Findings

NGC 7031 is approximately 224 million years old at 831 parsecs.

NGC 7086 is approximately 178 million years old at 955 parsecs.

The clusters are unlikely to be a true binary pair due to differences in age and distance.

Abstract

We present a CCD BV photometry of the possible binary open star cluster NGC 7031/NGC 7086. The aim is to confirm or disprove their common nature on the grounds of their age and distance. An age of 224 $\pm$ 25 Myr and distance 831 $\pm$ 72 pc was determined for NGC 7031 and 178 $\pm$ 25 Myr, 955 $\pm$ 84 pc for NGC 7086, respectively. Based on these differences in age and distance we conclude that the two clusters are most likely not formed together from one and the same Giant Molecular Cloud and thus are not a true binary cluster.