Earthlight

Even though many of Clarke's science fiction novels take place in rather similar futures—Earthlight, A Fall of Moondust, The Sands of Mars, Rendezvous with Rama—the human background is never quite the same and they do not form a series.

The trigger for hostilities is the publication of a research paper suggesting that the Moon may have previously unsuspected heavy metal resources which Earth proposes to monopolise.

The Earth government's intelligence agency suspects that confidential information concerning the exploitation of these mineral riches may be being leaked to the Federation and presses an accountant, Bertram Sadler, into service.

The rising political tension is accompanied by the observatory staff enjoying the good fortune of observing a nearby supernova explosion in the constellation of Draco.

A climactic battle between three Federation cruisers and the fortified mining installation ("Project Thor") is played out near Mount Pico close to the lunar observatory.

Many years later the commander of the Acheron writes his memoirs and reveals that information had reached the Federation from "One of Earth's most distinguished astronomers, now living in honoured retirement on the Moon".

The novel concludes with Molton enlightening Sadler and the reader as to the brilliant technical subterfuge with which he transmitted information, namely that he used the observatory's main telescope as a transmitter by placing a modulated ultra-violet source at its prime focus.

[2] Anthony Boucher praised the novel as a convincingly real, scientifically detailed story of the near future, yet infused with that sense of wonder and excitement that we sometimes think vanished from literature about the time our voices changed.

The space battle in Earthlight is the only time Clarke wrote such a scene, and it was intended as a specific homage to the attack on the Mardonalian fortress in chapter seven of E. E. Smith's Skylark Three.