There are fewer people who have discovered a comet than those who have been to space.

While comets are now often discovered by amateurs—some analyze open images from scientific telescopes, some do it through their telescope.

https://en.wikipedia.org/wiki/Category:Discoverers_of_comets
https://en.wikipedia.org/wiki/List_of_space_travellers_by_first_flight

Even the first interstellar comet (which came to us from another star) was discovered by an amateur astronomer from Crimea using homemade telescopes.

https://en.wikipedia.org/wiki/Gennadiy_Borisov