Astronaut Walter Schirra featured in Tom Wolfe's book, The Right Stuff. Photograph: NASA/Getty

If fortune favours the brave, then there is something heartening as well as saddening in the news that Walter "Wally" Schirra has died of natural causes at the age of 84.

For Schirra was one of the Mercury Seven, the USA's original astronauts. He might well have perished in 1962, when he became the third American in orbit; or in 1968, when his Apollo 7 mission was the first to blast off in the wake of a launchpad-test fire that killed his Mercury cohort Gus Grissom and two others (Schirra was in the back-up crew); or long before NASA was even established, when he flew combat missions over Korea as a Navy pilot.

Inevitably, Schirra's death sends me back to The Right Stuff, Tom Wolfe's masterful account of the Mercury programme. It's a book I reread every so often, mostly for the sheer joy of it, but also as a reminder not just of the hope we used to place in science, but the pride we used to take in heroism.

And as The Right Stuff demonstrates, heroism is Wolfe's greatest subject. We tend to think of Wolfe as a satirical recorder of debased mores. With good reason: he's been at it since the 1960s. But satire without some kind of moral underpinning is mere sneering, and while Wolfe was deftly skewering those vanities he would eventually, and memorably, heap with magnificent disgust upon a great and crackling bonfire, he never failed to emphasise what he saw as the alternative. Through the 1960s and 1970s, even writing with a sharp and robust nib dipped in acid, he seemed to believe that those qualities which stood in opposition to solipsism, pettiness, conceit and cupidity - principally, that good-humoured, unshowy mettle which epitomised the Mercury Seven - were still to be found somewhere in the American psyche.

There is in this something of the sedentary scribe's vicarious worship of men of action; but then, why not? If Wolfe had been British, he might have turned his talents to lauding the Few of the RAF. Being American, and possessed of a uniquely American voice - one that combined droll distance with hectic, here-and-now immediacy - he focused his most gleeful adoration on his own country's airmen, both in military service and in space. Although anyone willing to hurtle along at lethal speeds in some terrible contraption, whether for duty, national pride or the sheer hell of it, and then act afterwards as if it were no matter at all, commanded his respect. His justly celebrated 1964 piece on Junior Johnson, the stock car driver, was titled The Last American Hero. It introduced the phrase "good ol' boy" to general use; and while those words may now hold less savoury connotations, there is no doubt Wolfe was serious about the "good" part.

But if Johnson really numbered, in Wolfe's view, among a dying breed, does this explain the increasing sourness of Wolfe's work over the years? It could simply be a natural consequence of getting older. Or perhaps his America deserves that ever more jaundiced eye. When one hears the cockpit recordings of US pilots involved in "friendly fire" incidents in Iraq, it's hard to imagine them hurtling perilously around the planet in a glorified soup can one December day, making this deadpan report to Mission Control: "I see a command module and eight smaller modules in front. The pilot of the command module is wearing a red suit." Followed by the strains of Jingle Bells on a smuggled harmonica. That was Wally Schirra, who - along with his Mercury fellows - found in Tom Wolfe the perfect chronicler.