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NERVA XE in an engine test stand
NERVA XE in an engine test stand

The Nuclear Engine for Rocket Vehicle Application (NERVA) was a rocket engine development program intended to establish a technology base for nuclear thermal rocket systems for space missions, as this promised to be more efficient than chemical rockets. NERVA was a joint effort of the Atomic Energy Commission and NASA, and was managed by the Space Nuclear Propulsion Office (SNPO). NERVA was considered a successful program in that it met or exceeded its program goals and demonstrated that nuclear thermal rocket engines were a feasible and reliable tool for space exploration. At the end of 1968 the SNPO deemed that the latest NERVA engine, the XE (pictured), met the requirements for a human mission to Mars. It had strong political support but was canceled by President Richard Nixon in 1973. Although NERVA engines were built and tested largely with flight-certified components and were deemed ready for integration into spacecraft, they never flew in space. (Full article...)

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Part of the façade of the Unité d'Habitation of Berlin

The Unité d'Habitation of Berlin is a 1958 apartment building located in Berlin, a seminal example of modernist architectural design. Designed by Swiss-French architect Le Corbusier, it embodies the principles of his concept of unité d'habitation, an innovative response to post–World War II urban-housing challenges. The building is distinguished by its functionalism and efficiency. It encompasses 530 modular residential units, distributed across seventeen floors. The exterior façade, seen here in 2021, is characterized by the employment of rough-cast concrete, with colors designed by Le Corbusier together with the painter Fernand Léger.

Photograph credit: Matthias Süßen

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