Not just deep-space probes; Dragon, Orion, and I think Starliner all use hypergols. Plenty of satellites do as well, though I think there's a trend towards usin

Not just deep-space probes; Dragon, Orion, and I think Starliner all use hypergols. Plenty of satellites do as well, though I think there's a trend towards using various sorts of electric propulsion. Really, the big misprediction of the book (looking at chapter 13, "What Happens Next") is that it doesn't consider missiles (and some upper/deep-space stages) moving to solid propellant; but it's a book about liquid propellants, so I'm not too surprised.