| Invention or discovery | Date | Inventor or discoverer | Type |
|---|---|---|---|
| NGC 2860 | March 17, 1884 | Édouard Stephan | astronomical radio source |
| NGC 2922 | March 18, 1884 | Édouard Stephan | astronomical radio source |
| NGC 2766 | March 22, 1884 | Édouard Stephan | spiral galaxy |
| NGC 3864 | March 23, 1884 | Édouard Stephan | spiral galaxy |
| NGC 2987 | March 25, 1884 | Édouard Stephan | spiral galaxy |
| NGC 2971 | March 26, 1884 | Édouard Stephan | spiral galaxy |
| NGC 3542 | March 26, 1884 | Édouard Stephan | radio galaxy |
| NGC 4239 | April 1884 | Carl Frederik Pechüle | elliptical galaxy |
| NGC 3040A | April 6, 1884 | Édouard Stephan | lenticular galaxy |
| NGC 1213 | October 14, 1884 | Lewis A. Swift | low-surface-brightness galaxy |
| NGC 1212 | October 18, 1884 | Lewis A. Swift | lenticular galaxy |
| NGC 1264 | October 19, 1884 | Guillaume Bigourdan | low-surface-brightness galaxy |
| NGC 1259 | October 21, 1884 | Guillaume Bigourdan | lenticular galaxy |
| NGC 1283 | October 23, 1884 | Guillaume Bigourdan | elliptical galaxy |
| NGC 7459 | October 26, 1884 | Lewis A. Swift | interacting galaxies |
| NGC 1121 | November 9, 1884 | Lewis A. Swift | lenticular galaxy |
| NGC 975 | November 9, 1884 | Lewis A. Swift | lenticular galaxy |
| NGC 1265 | November 14, 1884 | Guillaume Bigourdan | elliptical galaxy |
| NGC 1271 | November 14, 1884 | Guillaume Bigourdan | elliptical galaxy |
| NGC 946 | December 12, 1884 | Édouard Stephan | lenticular galaxy |
| NGC 903 | December 13, 1884 | Édouard Stephan | lenticular galaxy |
| NGC 904 | December 13, 1884 | Édouard Stephan | elliptical galaxy |
| NGC 1178 | December 17, 1884 | Guillaume Bigourdan | star |
| NGC 1517 | December 23, 1884 | Édouard Stephan | spiral galaxy |
| NGC 3736 | 1885 | Ralph Copeland | spiral galaxy |
| NGC 927 | January 18, 1885 | Johann Palisa | spiral galaxy |
| NGC 2514 | January 19, 1885 | Édouard Stephan | spiral galaxy |
| NGC 2484 | January 21, 1885 | Édouard Stephan | lenticular galaxy |
| NGC 2638 | January 21, 1885 | Édouard Stephan | lenticular galaxy |
| NGC 1297 | February 1885 | Edward Emerson Barnard | lenticular galaxy |
| NGC 2357 | February 6, 1885 | Édouard Stephan | spiral galaxy |
| NGC 2424 | February 6, 1885 | Édouard Stephan | spiral galaxy |
| NGC 2393 | February 7, 1885 | Édouard Stephan | spiral galaxy |
| NGC 2406 | February 7, 1885 | Édouard Stephan | elliptical galaxy |
| NGC 2407 | February 7, 1885 | Édouard Stephan | lenticular galaxy |
| NGC 2411 | February 7, 1885 | Édouard Stephan | elliptical galaxy |
| NGC 2540 | February 10, 1885 | Édouard Stephan | spiral galaxy |
| NGC 2617 | February 12, 1885 | Édouard Stephan | spiral galaxy |
| NGC 2398-1 | February 22, 1885 | Édouard Stephan | spiral galaxy |
| NGC 2581 | March 7, 1885 | Édouard Stephan | spiral galaxy |
| NGC 2657 | March 7, 1885 | Édouard Stephan | lenticular galaxy |
| NGC 3553 | March 13, 1885 | Guillaume Bigourdan | lenticular galaxy |
| NGC 4166 | March 15, 1885 | Wilhelm Tempel | lenticular galaxy |
| NGC 3007 | March 16, 1885 | Édouard Stephan | lenticular galaxy |
| NGC 4155 | April 6, 1885 | Lewis A. Swift | elliptical galaxy |
| NGC 3908 | April 10, 1885 | Lewis A. Swift | brightest cluster galaxy |
| NGC 2892 | May 11, 1885 | Lewis A. Swift | elliptical galaxy |
| NGC 1077 | August 16, 1885 | Lewis A. Swift | spiral galaxy |
| NGC 1086 | August 20, 1885 | Lewis A. Swift | spiral galaxy |
| NGC 1224 | August 20, 1885 | Lewis A. Swift | lenticular galaxy |
| NGC 389 | September 6, 1885 | Lewis A. Swift | lenticular galaxy |
| NGC 2523 | September 7, 1885 | Edward D. Swift | spiral galaxy |
| NGC 2544 | September 7, 1885 | Lewis A. Swift | spiral galaxy |
| NGC 2550 | September 7, 1885 | Lewis A. Swift | spiral galaxy |
| NGC 804 | September 7, 1885 | Lewis A. Swift | lenticular galaxy |
| NGC 933 | September 11, 1885 | Lewis A. Swift | spiral galaxy |
| NGC 746 | September 12, 1885 | Lewis A. Swift | low-surface-brightness galaxy |
| NGC 935 and IC 1801 | September 18, 1885 | Lewis A. Swift | interacting galaxy |
| NGC 801 | September 20, 1885 | Lewis A. Swift | spiral galaxy |
| 252 Clementina | October 11, 1885 | Henri Joseph Anastase Perrotin | asteroid |