A story of live and astronomy told over the course of twenty years through the lives of two improbable best friends Thomas Hart, a journalist on the Essex Chronicle, and Grace Macauley (17),  small and plump, with skin that went brown by the end of Maym and who is “by nature a thief if she found a thing to be beautiful , but not hers”. worshipers at the Bethesda Baptist chapel in the small fictional Essex town of Aldleigh.  Thomas who is 50 and writes a column for the newspaper on scientific and astronomical topics, which brings him into connection with James Bower, curator of the local museum. The pair are kindred spirits although separated in age by three decades, from between their commitment to religion and their desire  for more. But their friendship is threatened by the arrival of love. Thomas falls for James Bower, who runs the local museum, and together they develop an obsession with the vanished nineteenth-century female astronomer Maria  Veda, said to haunt a nearby manor. Inspired by Maria, and the dawning realisation James make  not reciprocate his feelings, Thomas finds solace studying the night skies. Could astronomy offer as much wonder as divine or earthly love?

Meanwhile Grace meets Nathan, a fellow sixth former who represents a different, wilder kind of life. They are drawn passionately together, but quickly pulled apart, casting Grace into the wider world and far away from Thomas.

Enlightenment is an old-fashioned novel of ideas, riffing on science and religion, where people thresh around under heightened emotions – one experiences what he describes as “ecstatic misery” as these people live in a world where someone can, like a comet, disappear and then reappear decades later.

Grace loves Nathan, and Thomas loves James in a complicatedly. His nature was an affront to god, brought up in church, he is torn:” Do you think you lose your faith, because your faith does not want you? That would ne easy. Worse, James is happily married  and does not love Thomas in return. The two men are brought together by their discovery of letters from a local astronomer Maria Vaduva, who went missing in the late 19th century. Their encounters take place under there transit – and perhaps the influence – of the Hale-Bopp comet as it makes its approach to Earth in early 1997. The heaven of religion and the heavens filled with stars each make claims on the characters their “bodies moved by forces not possible to resist”.

Enlightenment is about how human connect, how they find meaning -with strong dialogue  where these people live in a world where passions last for implausibly long times.

In time, the mysteries of Aldleigh are revealed, bringing Thomas and Grace back to each other and to a richer understanding of love, of the nature of the world, and the sheer miracle of being Alive.

Enlightenment by Sarah Perry, Jonathan Cape £20/ Mariner $28, 400 pages.