1 янв 1890 г. - Reflectors were recognized
Описание:
40 inches was close to the maximum feasible aperture for refracting telescopes. If telescopes with significantly larger apertures were to be built, they would have to be reflecting telescopes.Добавлено на ленту времени:
Дата:
1 янв 1890 г.
Сейчас
~ 135 г назад