Abell 1689 is a galaxy cluster in the constellation Virgo over 2.3 billion light-years away.

[4] It has the largest system of gravitational arcs ever found.

[5] Abell 1689 shows over 160,000 globular clusters, the largest population ever found.

[6] There is evidence of merging and gases in excess of 100 million degrees.

[5] The very large mass of this cluster makes it useful for the study of dark matter and gravitational lensing.