
At sunrise, on the 6th of June the transit of Venus will be visible in the area where I live.
Getting up early is not an obstacle for me, but I suspect I won’t see that much of sun (just to not mention little Venus) on that day, since I suspect it will be a rainy day, or in the best case a very cloudy one.
So, if I can’t be able to see with my own eyes the passage of what might look like a little mincing mole on the face of the “Roi-Soleil”, the Sun King, I can at least try to imagine what these planetary transits might mean in the past times.
History is always a fascinating source of episodes, circumstances and anecdotes.
Getting up early is not an obstacle for me, but I suspect I won’t see that much of sun (just to not mention little Venus) on that day, since I suspect it will be a rainy day, or in the best case a very cloudy one.
So, if I can’t be able to see with my own eyes the passage of what might look like a little mincing mole on the face of the “Roi-Soleil”, the Sun King, I can at least try to imagine what these planetary transits might mean in the past times.
History is always a fascinating source of episodes, circumstances and anecdotes.

The possibility to utilise the transits of Venus to calculate the distance of the earth from the Sun was conceived at the beginning by an astronomer called Halley, the one who gave his name to the famous comet, just to see whom we are talking about. But astronomical rhythms are not always suitable for human ones…Halley never saw the transit of Venus over the sun, but he had planted the seed of the idea.
Nine years after Halley’s death, the transits of Venus expected in 1761
and 1769 provoked what we might call the first scientific globalization.

150 astronomers from different countries took long and perilous trips from India to Siberia, from U.S.A. to remote island of Pacific Ocean to check the time Venus needed to go through its passage over the sun.
Various famous characters of that time were involved in that enormous global experiment, as the mythical English explorer James Cook, Benjamin Franklin, King Georges III of England, the Empress Ekaterina of Russia and many others, besides them, a variegated mass of astronomers. Among them there was probably one of the most unfortunate and plagued by bad luck astronomers of all ages, the French Guillaume Joseph Hyacinthe Jean-Baptiste LeGentil de la Galaisière, whom I intend to offer at least this semi-serious tribute to, quoting his whole name.
It must be said that all the astronomers who bravely took all those long trips had various unexpected and not always positive vicissitudes.
A certain abbot Chappe, whose destination had decided to be Siberia, travelled for 3200 kilometres to reach a very remote Siberian town surrounded by Cossacks’ tribes and local Tatar inhabitants.
Another French astronomer, Pingré, who suffered with rheumatism and gout, sailed among pirates and hostile British ships to reach his destination, the island of Rodriguez and once he was there it was raining so heavily on the island that he could see only the last fragment of the exist of Venus from the disc of sun…
Various famous characters of that time were involved in that enormous global experiment, as the mythical English explorer James Cook, Benjamin Franklin, King Georges III of England, the Empress Ekaterina of Russia and many others, besides them, a variegated mass of astronomers. Among them there was probably one of the most unfortunate and plagued by bad luck astronomers of all ages, the French Guillaume Joseph Hyacinthe Jean-Baptiste LeGentil de la Galaisière, whom I intend to offer at least this semi-serious tribute to, quoting his whole name.
It must be said that all the astronomers who bravely took all those long trips had various unexpected and not always positive vicissitudes.
A certain abbot Chappe, whose destination had decided to be Siberia, travelled for 3200 kilometres to reach a very remote Siberian town surrounded by Cossacks’ tribes and local Tatar inhabitants.
Another French astronomer, Pingré, who suffered with rheumatism and gout, sailed among pirates and hostile British ships to reach his destination, the island of Rodriguez and once he was there it was raining so heavily on the island that he could see only the last fragment of the exist of Venus from the disc of sun…

But let’s come back to our LeGentil, the unluckiest of all. He had left
on 1760 to India, but he could never reach his destination, because Pondicherry in the meanwhile had been captured by British soldiers, so he missed the transit of 1761, because he could see it only from a ship and the rolling prevented him from taking all necessary
astronomical measurements. So he decided to take good advantage of the only chance he could still have and to remain in the area until 1769, the date of the other transit of the century.
Being - ironically for an astronomer- born probably under a bad star, LeGentil, who had nearly always enjoyed a very good and clear weather in his exotic place of temporary residence, had the most
cloudy day of all exactly on the 3rd of June of 1769 and, it’s useless to say it, he could not see absolutely anything in the merciless sky.
He had missed both his chances, nothing to do, but trying to go back home.
After various illnesses and troubles, 11 years after his departures, LeGentil managed to arrive back to Paris.
Do you think his bad fate had left him? Of course it had not…
When he was in Paris again at long last, he realized that he had been declared officially dead during his absence and his position at the Royal Academy of France had been taken by another person; his wife, considered widow, had married another man and all his patrimony had been sheared among various heirs.
on 1760 to India, but he could never reach his destination, because Pondicherry in the meanwhile had been captured by British soldiers, so he missed the transit of 1761, because he could see it only from a ship and the rolling prevented him from taking all necessary
astronomical measurements. So he decided to take good advantage of the only chance he could still have and to remain in the area until 1769, the date of the other transit of the century.
Being - ironically for an astronomer- born probably under a bad star, LeGentil, who had nearly always enjoyed a very good and clear weather in his exotic place of temporary residence, had the most
cloudy day of all exactly on the 3rd of June of 1769 and, it’s useless to say it, he could not see absolutely anything in the merciless sky.
He had missed both his chances, nothing to do, but trying to go back home.
After various illnesses and troubles, 11 years after his departures, LeGentil managed to arrive back to Paris.
Do you think his bad fate had left him? Of course it had not…
When he was in Paris again at long last, he realized that he had been declared officially dead during his absence and his position at the Royal Academy of France had been taken by another person; his wife, considered widow, had married another man and all his patrimony had been sheared among various heirs.

LeGentil didn’t lose his heart and with the same determined
consistence with which he had tried to see the transits of Venus, he insisted to get his Academic position and his patrimony back; wisely he decided it was not the case to insist to get back also the wife.
He was successful, at least once in his life, and he even found a new love (ah, maybe a side effect of Venus?), got married again at his turn and had a daughter and could enjoy still 21 years of serene family life.
Even blind fate can by chance be fair at the end…