Three months before the last transit of Venus this century.
“The transits are an interesting marker of mankind’s technological advances,” says Dr Thomas Widemann of the Observatoire de Paris. “In the eighteenth century, pendulum clock allowed accurate timings during a Venus transit – to measure the astronomical unit. In the 19th century, we had a new tool in photography. In the 21st century, we are able to observe the phenomenon from space and from Earth at the same time.”
Above, a photo of Venus at the point of egress – its exit from the face of the Sun – shot from the Roque de los Muchachos Observatory on the island of Las Palma in the Canary Islands during the last transit in 2004.
More about the Paris observatory’s preparations for this year here.