The Odyssey is one of the great works of ancient Western literature, written eight centuries before the birth of Christ and four centuries after the fall of Troy.

Generations of classicists have pored over the many lines of Homer's epic description of the long journey taken by the hero Odysseus to his home island of Ithaca.

Now two scholars have found evidence to support the idea that one line, in the poem's 20th book, refers to a total solar eclipse that occurred on April 16, 1178 BC - the day when Odysseus returned home to kill his wife's suitors. If true, this would date the fall of Troy itself to precisely 1188 BC.

It takes Odysseus 10 years to reach Ithaca after the 10-year Trojan war. During his time away, his young son, Telemachus, has grown into a man and his faithful wife, Penelope, is besieged by unruly suitors.

The Odyssey is the story of a long and great journey involving the beautiful nymph Calypso - who enslaves Odysseus for seven years as her lover - helpful divinities such as Athena and vengeful gods such as Poseidon.

Odysseus eventually escapes from Calypso, survives a shipwreck where all his compatriots are drowned and is befriended by the Phaeacians, a race of skilled mariners who finally deliver the hero safely to Ithaca, where he takes on the guise of a beggar.

It is during this later phase of The Odyssey that Homer is said to make reference to a total solar eclipse. The key phrase comes in a speech by the seer Theoclymenus, who foresees the deaths of the unruly young men who sought the hand of Penelope while Odysseus was away. It ends with the words: "The Sun has been obliterated from the sky, and an unlucky darkness invades the world."

The idea that The Odyssey refers to a total solar eclipse, when the Moon blocks out the Sun completely was first suggested by ancient scholars, but it was only in the 1920s that astronomers were able to calculate that such an eclipse over Greece around that time could only have taken place on April 16, 1178 BC.

But few people were convinced that the passage in The Odyssey was actually a reference to a mythical total solar eclipse, never mind a real one. It might just have been poetic licence. But two modern astronomers believe they have convincing evidence to support the April 16 eclipse by analysing other passages in the poem that refer to four other astronomical events that are known to occur quite independently of one another.

Instead of looking at when a solar eclipse occurred in history, as other astronomers had done, they investigated the timing of a new moon, the simultaneous appearance of two stellar constellations in the evening sky, and appearances of the planets Mercury and Venus. All four phenomena are mentioned in The Odyssey which gave Constantino Baikouzis, of the Observatorio Astronomico de La Plata in Argentina, and Professor Marcelo Magnasco, of the Rockefeller University in New York, another way of checking the date when Odysseus is supposed to have returned to his home on Ithaca to kill his wife's suitors.