Things are either forbidden by the laws of physics or possible, so yeah it is physically feasible. But it is not within the bounds of reality because the cores

Things are either forbidden by the laws of physics or possible, so yeah it is physically feasible. But it is not within the bounds of reality because the cores for those two reactors are millions of dollars and the weights don't include the shielding necessary to operate without dying. Those space reactors are indeed awesome. Nuclear has a rich future in space in almost all possible scenarios where humans continue to exist.