| Invention or discovery | Date | Inventor or discoverer |
|---|---|---|
| Messier 2 | September 11, 1746 | Giovanni Domenico Maraldi |
| NGC 2156 | September 27, 1826 | James Dunlop |
| NGC 2159 | November 6, 1826 | James Dunlop |
| NGC 1916 | November 3, 1834 | John Frederick William Herschel |
| NGC 2162 | November 30, 1834 | John Frederick William Herschel |
| NGC 2231 | December 23, 1834 | John Frederick William Herschel |
| NGC 2173 | February 8, 1836 | John Frederick William Herschel |
| NGC 2190 | February 8, 1836 | John Frederick William Herschel |
| NGC 2209 | February 8, 1836 | John Frederick William Herschel |
| NGC 1754 | November 12, 1836 | John Frederick William Herschel |
| Palomar 6 | 1952 | George O. Abell |