There is more than one irony, I think. NASA, for its own purposes, has defined life: a self-sustaining chemical system capable of Darwinian evolution.
Somebody (several somebodys) has raised the issue of a fetus – is it alive by NASA definition – and the political and ethical issues the question arouses. Let me simply observe that no life (of which we know) is sustainable in an environment that is not suitable for that life’s existence. So, a human fetus is no more in an environment suitable for its sustenance than any other life-form. And, in many instances anyway, I’m not sure what “Darwinian evolution” (micro? macro? natural selection?) has to do with a definition of life.
I think it probably has to do with the successful communication of genetic information from one generation to the next, that is also capable of adapting to environmental changes. By that standard, I suppose one could write a computer virus that is also "alive."