Wilhelm Struve discovered 7 NGC objects between 1824-26 while searching for double stars with the 9.6" f/17.8 Fraunhofer refractor at Dorpat (installed 1824). They are contained in his Catalogus novus generalis stellarum duplicium et multiplicium, Dorpat 1827 (the entries are desginated with S). Four objects are listed in the appendix (Nebulae detectae). Two objects are also contained in Auwers, William Herschel's Verzeichnisse von Nebelflecken und Sternhaufen, Königsberg 1862.

In nearly chronological order Struve's discoveries are: NGC 629 (#2 in appendix, Auwers 16), which is only a star group; the planetary nebulae NGC 6210 (#5) in Herkules and NGC 6572 (#6) in Sagittarius; NGC 6648 (#7, Auwers 41) in Draco, which is only a double star; NGC 2202 (S 885), an open cluster with a central double star in Orion; the open cluster NGC 6871 (S 2630) in Cygnus, and NGC 6873 (S 2631) in Sagitta, which is only a star group. Both objects contain a double star, measured by Struve. Don't disturb these Struve objects with those found by his son Otto Struve.

Obituary: AN 63, 241 (1864); MNRAS 25, 83 (1865), whis is identical with: Astron. Reg. 3, 89 (1865)