A prototype of the Soviet R-16 intercontinental ballistic missile exploded on the launch pad at the Baikonur Cosmodrome in the Kazakh SSR.

The R-16 was the first successful intercontinental ballistic missile deployed by the Soviet Union. In the West it was known by the NATO reporting name SS-7 Saddler, and within Russia, it carried the GRAU index 8K64.

The Nedelin catastrophe or Nedelin disaster, known in Russia as the Catastrophe at Baikonur Cosmodrome, was a launch pad accident that occurred on 24 October 1960 at the Baikonur Cosmodrome in Soviet Kazakhstan. As a prototype of the R-16 intercontinental ballistic missile was being prepared for a test flight, an explosion occurred when the second stage engine ignited accidentally, killing an unknown number of military and technical personnel working on the preparations. Despite the magnitude of the disaster, information was suppressed for many years and the Soviet government did not acknowledge the event until 1989. With more than 54 recognized casualties, it is the deadliest disaster in space exploration history. The catastrophe is named for the Chief Marshal of Artillery Mitrofan Ivanovich Nedelin, who was the head of the R-16 development program and perished in the explosion.

The Baikonur Cosmodrome is a spaceport operated by Russia within Kazakhstan. Located in the Kazakh city of Baikonur, it is the largest operational space launch facility in terms of area. All Russian crewed spaceflights are launched from Baikonur.

The Kazakh Soviet Socialist Republic, also known as Soviet Kazakhstan, the Kazakh SSR, KSSR, or simply Kazakhstan, was one of the constituent republics of the Soviet Union (USSR) from 1936 to 1991. Being located in northern Central Asia, the Kazakh SSR was created on 5 December 1936 from the erstwhile Kazakh ASSR, which was an autonomous republic of the Russian SFSR. It shared borders with its fellow Soviet republics of Russia, Kyrgyzstan, Turkmenistan and Uzbekistan, while also sharing an international border with the People's Republic of China.