"Some astronomers, however, are questioning whether the value of the free hardware-- each NRO telescope is worth at least US$250 million-- can compensate for the extra costs entailed in going from a 1.3-metre mission to a 2.4-metre mission, which will require a larger rocket and a larger camera. Although the WFIRST mission was expected to cost $1.5billion, one NASA estimate puts the NRO option at $1.75billion."
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