English scientist who studied the spectra of solar prominences and
sunspots. Through his pioneering work in spectroscopy, he discovered
the existence of helium.
Lockyer was born in Rugby, the Midlands, and began as an amateur astronomer.
In 1869 he founded the scientific journal Nature, which he was to edit
for 50 years. He was director of the Solar Physics Observatory in South
Kensington, London, 1890-1911.
In 1869 Lockyer attached a spectroscope to a 15-cm/6-in telescope and
used it to observe solar prominences at times other than during a total
solar eclipse. Although Lockyer had been the first to think of it, the
same idea had occurred to French astronomer Pierre Janssen, then working
in India, and they simultaneously notified the French Academy of Sciences
of the same result. Later they worked together, Janssen providing the
observations of the Sun's spectrum that led to the discovery of helium.
Lockyer also developed the theory that Stonehenge is oriented towards
the direction in which the Sun rises at the time of the summer solstice.
From the gradual change in position of the solstitial sunrise, he calculated
that the monument must date from 1840 BC, plus or minus 200 years -
later confirmed by radiocarbon dating.