History

Until 1781, the known solar system consisted of six planets.  On March 13 of that year, astronomer William Herschel observed a faint object in the constellation Gemini and noted that it moved slowly relative to the background stars. First thinking it a comet, Herschel later correctly identified it as a …

In the summer of 1989, NASA’s Voyager 2 became the first spacecraft to fly by Neptune, its final planetary encounter. Managed by the Jet Propulsion Laboratory in Pasadena, California, Voyagers 1 and 2 were a pair of spacecraft launched in 1977 to explore the outer planets. Initially targeted only to …

Archaeological records show that astronomy is one of the first natural sciences developed by early civilisations all over the globe. Ancient astronomers could perform only limited investigations of the sky, using rudimentary aids to the human eye. Even so, humankind had already begun the measurement of the positions of celestial …

بداية  علم الفلك الحديث :   وضع أفلاطون القواعد لعلم الفلك الإغريقي ووضع أر سطو وفيثاغورس نظريات مركزية الأرض. فحوالي سنة 140 بعد الميلاد اقترح بطليموس الفلكي الاسكندراني في كتابه (المجسطي) تمثيلا شاملا للكون وهو تمثيل هندسي في طبيعته يضع الأرض مركزاً للكون ويجعل القمر والشمس والكواكب تدور حولها والنجوم …