NGC 869 and NGC 884: A Double Open Cluster . ... Open clusters NGC 869 and NGC 884, however, are doubly impressive. Also known as "h and chi Persei", this unusual double cluster , shown above , is bright enough to be seen from a dark location without even binoculars. Although their discovery surely predates written history , the Greek astronomer Hipparchus notably cataloged the "double cluster ". ... NASA Web Site Statements, Warnings, and Disclaimers . NASA Official: Jay Norris. ...