This introductory chapter briefly recalls the advent of the total eclipse of the Sun, on June 30, 1973, to be observed onboard the supersonic aircraft Concorde-001, which is the subject of Part I of this book. Humans have observed total solar eclipses since millennia, but only in 1912 and afterwards began to do it from aircrafts. The understanding of the faint light, briefly appearing around the eclipsed Sun during total eclipses and called the corona, was slow but fertile. Although a detailed description of the science of the corona is presented in Part II of this book, Chapter 1 outlines some of its current and basic understanding. At sunrise on the same day, far to the west in Dutch Guiana (now Surinam), the tree frogs of the species Hyla calcarata began to chorus, despite the unusual time of day. For indeed, it was there on the equator that the great dark disk formed by the Moon’s shadow on the surface of the Earth, surrounded by penumbra, began its race toward the east, moving at a speed of more than 2000 km an hour relative to the ground, soon to cross the African coastline. Astronomers, who know how to predict not just the occurrence, but all the details of these eclipses, had explained how this one would be total at every point on the Earth that the shadow would sweep past and partial in each region falling only in the penumbra. Better still, in Africa, total obscurity would last, exceptionally, for 7 min, and the sky would be so dark that the stars would be visible even at mid-day. This record length would make it the eclipse of the century, as announced by the media. By around 10 o’clock in the morning, the black indentation had grown to block out almost half of the Sun’s disk. Slowly, a great white bird began to move across the tarmac at Las Palmas airport to position itself on the runway. Fitted out with a bright red survival suit—standard dress for test flight crew members, in case they need to be fished out of the sea—I found myself aboard Concorde 001 F-WTSS, the prototype of the future supersonic passenger aircraft to be flown by Air France and British Airways, with seven other astronomers. At the controls, André Turcat, the famous pilot who had directed all the test flights of this plane since 1969, and Jean Dabos, both kitted out with the same survival gear. The four other men making up the crew were ready at their posts: “Sierra Sierra, ready for takeoff,” announced the control tower. To within a second of the planned time, the beautiful aircraft took off into the trade winds, accompanied by the roar of its four jet engines, flying to meet the shadow of the Moon somewhere above the barren deserts of Mauritania.

Eclipses and Humankind

章节
发表日期：

2025年

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Pierre Léna,
Serge Koutchmy

摘要

This introductory chapter briefly recalls the advent of the total eclipse of the Sun, on June 30, 1973, to be observed onboard the supersonic aircraft Concorde-001, which is the subject of Part I of this book. Humans have observed total solar eclipses since millennia, but only in 1912 and afterwards began to do it from aircrafts. The understanding of the faint light, briefly appearing around the eclipsed Sun during total eclipses and called the corona, was slow but fertile. Although a detailed description of the science of the corona is presented in Part II of this book, Chapter 1 outlines some of its current and basic understanding. At sunrise on the same day, far to the west in Dutch Guiana (now Surinam), the tree frogs of the species Hyla calcarata began to chorus, despite the unusual time of day. For indeed, it was there on the equator that the great dark disk formed by the Moon’s shadow on the surface of the Earth, surrounded by penumbra, began its race toward the east, moving at a speed of more than 2000 km an hour relative to the ground, soon to cross the African coastline. Astronomers, who know how to predict not just the occurrence, but all the details of these eclipses, had explained how this one would be total at every point on the Earth that the shadow would sweep past and partial in each region falling only in the penumbra. Better still, in Africa, total obscurity would last, exceptionally, for 7 min, and the sky would be so dark that the stars would be visible even at mid-day. This record length would make it the eclipse of the century, as announced by the media. By around 10 o’clock in the morning, the black indentation had grown to block out almost half of the Sun’s disk. Slowly, a great white bird began to move across the tarmac at Las Palmas airport to position itself on the runway. Fitted out with a bright red survival suit—standard dress for test flight crew members, in case they need to be fished out of the sea—I found myself aboard Concorde 001 F-WTSS, the prototype of the future supersonic passenger aircraft to be flown by Air France and British Airways, with seven other astronomers. At the controls, André Turcat, the famous pilot who had directed all the test flights of this plane since 1969, and Jean Dabos, both kitted out with the same survival gear. The four other men making up the crew were ready at their posts: “Sierra Sierra, ready for takeoff,” announced the control tower. To within a second of the planned time, the beautiful aircraft took off into the trade winds, accompanied by the roar of its four jet engines, flying to meet the shadow of the Moon somewhere above the barren deserts of Mauritania.