1970 in spaceflight 1970 in spaceflight Japan and China each launched their first satellites in 1970, bringing the total number of nations with independent launch capability to five. Apollo 13 was launched; after suffering an explosion in deep space it had to circumnavigate the moon and use the LM as a life boat. Apollo 13 was a successful disaster in which the crew survived. The Soviet space program continued its Luna program with Luna 17, which delivered the robotic Lunokhod 1 rover to the lunar surface, and Luna 16, which achieved the first unmanned lunar sample return. The Soviets also continued the success
Apollo program as a "life boat" to return to Earth. Another NASA review board was convened to determine the cause, which turned out to be a combination of damage of the tank in the factory, and a subcontractor not making a tank component according to updated design specifications. Apollo was grounded again, for the remainder of 1970 while the oxygen tank was redesigned and an extra one was added. The contracted batch of 15 Saturn Vs were enough for lunar landing missions through Apollo 20. NASA publicized a preliminary list of eight more planned landing sites, with plans to increase the mass