How Huggins changed observational astronomy

Sir William Huggins was an English astronomer who revolutionised observational astronomy. By taking to spectroscopic methods and applying them to astronomy, Huggins handed astronomers with new tools to answer existing questions. A.S.Ganesh takes a look at how this self-taught astronomer went about his business...

A painting of the Great Comet of 1881.

The comet C/1881 K1 is a long-distance comet that was discovered in 1881. Also called the Great Comet of 1881 owing to the brightness at its last apparition, this comet was among the brightest to have made its appearance in the 19th Century. Not only that, the first photographic spectrum of a comet was also performed on this comet by the English astronomer Sir William Huggins.

Painting of Sir William Huggins by John Collier.

Born in London in 1824, Huggins was a self-taught amateur astronomer who turned out to make a difference in the field he chose for himself. In fact, his pull towards astronomy was so strong that it is believed that he sold his family’s London silk shop as a 30-year-old to devote himself completely to his growing interest.

He started by building himself a private observatory at Tulse Hill, London in 1856. Using this, he started taking observations and recorded them diligently. And when spectrum analysis made its way, Huggins was among the first to apply it to astronomy. His pioneering work in celestial spectroscopy, which involved the technique of splitting starlight into its various wavelengths, brought him fame in the 1860s.

Many firsts

Some of Huggins’ first observations helped him show that stars are composed of the same elements that occur terrestrially, be it in the Sun or the Earth. He was also the first to observe the emission lines in the spectra of nebulae, which enabled him to settle the debate regarding their composition.

By 1868, Huggins became the first to employ the Doppler shift of a star’s spectral lines to measure its radial velocity. This technical innovation turned out to be rather important in studying the universe – be it its structure or evolution.

A marriage and a partnership

Huggins married Margaret Lindsay in 1875 and the two worked together professionally as well. The fact that Margaret Huggins also had an interest in astronomy and scientific research worked to their advantage and she also made their work more systematic.

The Great Comet of 1881 gave the Huggins another first. On June 24, 1881, William made the first photographic spectrum of a comet when they turned their attention to this comet. William also discovered that the comet emitted cyanogen at violet wavelengths.

William was knighted in 1897, making him Sir William Huggins. By the time he died in 1910, he had done enough to make spectral analysis an invaluable tool in astronomy.

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The scare of 1910

It was mentioned that Huggins, in 1881, discovered that the comet emitted cyanogen, one of the cyanide group of chemicals, which can be lethal.

In 1910, months before Huggins’ death, this fact caused major panic among the public when it was known that the Earth would pass through the tail of Halley's comet.

While there was no real danger to life on Earth, claims by certain astronomers and sections of the media sparked anxiety throughout the world in the months leading to the comet’s approach.

The mass hysteria proved to be a dud as the comet passed by without any incident.