Bussard Ramjets: Possible but Impracticable

The Bussard ramjet won’t work as well as you think it could. A new study does the math on John Fishback’s contribution to the ramjet—gathering protons from the interstellar medium for the ramjet’s fusion drive via a magnetic scoop—and concludes that while it’s physically possible, there are substantial constraints: the cut-off speed is lower than expected, limiting the effects of time dilation, and the magnetic field would have to be something like 4,000 km wide and 150 million km long in order to work. In other words: for certain very preposterous values of physically possible. [Universe Today]

Further Reading on the Apollo Program

Apollo 11

We marked the 50th anniversary of Apollo 11 last week, which means that the next step is to put all our moon-landing related nostalgia away until the next milestone anniversary, or until another of the remaining Apollo astronauts dies.1

If, on the other hand, all this attention has piqued your interest in the moon landings, the Apollo program, and the history of crewed spaceflight generally speaking, I have some suggestions as to what you should watch and read next. There are, of course, plenty of books and documentaries on this subject, but these will give you a general overview, with increasing levels of detail.

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