In one of its less-reported actions last week, Nasa's LCROSS lunar mission last week gave Douglas Adams's Hitchhiker's Guide to the Galaxy the extra-planetary exposure it has always deserved. A Twitter feed from the satellite sent crashing onto the moon's surface on Friday channelled the voice of an improbably created sperm whale that discovers itself hurtling towards a different outer-space collision in Adams's much-loved story.

Published 30 years ago, the classic novel features two missiles, aimed at Zaphod Beeblebrox's spaceship the Heart of Gold, turned into a whale and a bowl of petunias by the vessel's Improbability Drive (at an Improbability Factor of 8,767,128 against). The whale spends the last few minutes of its life pondering its existence – "Ahhh! Woooh! What's happening? Who am I? Why am I here? What's my purpose in life? What do I mean by who am I?" – before it crashes into the surface of the planet Magrathea.

As Nasa's LCROSS spacecraft travelled towards the moon at more than 9,000 kilometres per hour on Friday afternoon, it tweeted in the whale's words: "And what's this thing coming toward me very fast? So big and flat and round ... it needs a big wide sounding name like 'Ow', 'Ownge', 'Round', 'Ground'! ... That's it! Ground! Ha! I wonder if it'll be friends with me?"

Then it crashed into the moon, unfortunately failing to produce the 10km plume of dust and rock which could have been scanned for evidence of frozen water. Nasa made no mention of Adams's bowl of petunias, which thought only "Oh no, not again" as it tumbled towards Magrathea.

"Many people have speculated that if we knew exactly why the bowl of petunias had thought that we would know a lot more about the nature of the universe than we do now," wrote Adams in 1979.

The 30th anniversary of The Hitchhiker's Guide has also been marked with the publication of a sixth book in Adams's series, written by children's author Eoin Colfer with the blessing of Adams's widow, Jane Belson, and published today. And Another Thing ... picks up from where Adams's Mostly Harmless ended, and has been heralded as a triumph despite initial trepidation from fans. "Colfer has pulled off the near-impossible," wrote Euan Ferguson in the Observer. "It's faithful to Adams's humour and, more important, it's also got his rhythm, the cadences and the footfalls that made his style so often (badly) imitated."

"Fans can put away the axes right now, because he has done a fine job," wrote Lisa Tuttle in the Times. "I haven't read anything in a long time that made me laugh as much as the battles on Planet Nano involving the elderly super-rich, their personal trainers and a sect of cheese-worshippers who cry, 'You will bring Edamnation down on us all!'"