I could hardly believe my eyes when I stumbled on the report in the Royal Astronomical Society’s archive. It transported me to 1:30am, 2nd September 1859, when the clipper ship Southern Cross was 84 days out of Boston and sailing in a living hell. Hailstones from above and waves from all around whipped the deck. When the wind-lashed spray fell to leeward, the crew noticed they were sailing in an ocean of blood.
Lifting their eyes skyward, they saw the reason for the pitching seascape having turned deepest red. Even through the clouds, the heavens were wreathed in an all-encompassing crimson glow, as if some terrible conflagration had engulfed the Earth.
It was a giant aurora, an unexplained phenomenon in the 19th century, whose eerie luminescence usually graced the polar skies. Most of the world had been gripped by the aurora that night. As it appeared, telegraph equipment burst into flames and compasses spun uselessly. Global communication and global navigation had been paralysed – and no one knew what had caused it.
For the next five years I unearthed one eyewitness report after another and researched the scientific efforts made by people to explain what had happened that night. One man stood out: wealthy amateur astronomer Richard Carrington, who happened to see an unprecedented solar explosion that preceded the gigantic aurora. He wrestled with the scientific establishment to prove the link between that explosion and the aurora on Earth. Then it hit me.
It hit me as powerfully as the aurora had hit the 19th century world. The global aurora had been a tipping point for astronomy. No longer were astronomers content to chart the position of the stars for navigation. Now, they wanted to understand the celestial objects, what they were and how they could affect us. This was the true birth of astrophysics, the branch of astronomy practiced by most of today’s astronomers.