• 17332-000_17006152_Vanguard.jpg Vanguard 1, © Technisches Museum Wien
Collection Area
Traffic & Transport
Aviation and Aerospace

Vanguard I


In 1958 the United States launched its second satellite, Vanguard 1, into orbit and, for the first time, there were also six silicon solar cells on board. There was still a great deal of scepticism about the new technology prior to the launch, so tried-and-tested mercury oxide-zinc batteries were also sent up into space at the same time, just to be on the safe side. The batteries worked reliably and, after twenty days, they were depleted as expected. By contrast the solar cells exceeded all expectations. They supplied the on-board transmitter with electricity for six years, paving the way for the breakthrough of photovoltaic systems. They have been a reliable and, above all, weight-saving energy source in space travel ever since.

Vanguard 1 weighed a mere 1.5 kg and had a diameter of just 16.5 cm, prompting the then Soviet Premier Nikita Khrushchev to refer to it jokingly as ‘the space grapefruit’. That ‘grapefruit’ continues to circle the Earth on a stable orbit to this day and is only expected to decay from orbit around the year 2198. Vanguard 1 is now the oldest man-made object in space. Indeed, all three satellites launched before 1958 (Sputnik 1, Sputnik 2 and Explorer 1) crashed shortly after lift-off.

Inv.Nr. 17332
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