September 17th 1764 the birth of John Goodricke.
John
Goodricke 1764-1786, One of the Fathers of Variable Star Astronomy
This is the
story of John Goodricke, one of the most talented astronomers of all time. Deaf
from a very early age, he had a tragically short life but his contribution to
astronomy was immense.
The
Goodrickes were an English aristocratic family with an ancestral home, Ribston
Hall, near Knaresborough in North Yorkshire. John was born in Groningen,
Holland on September 17th, 1764 to Henry and Levina. Sadly, after an illness
early in his life, the infant John was found to be deaf.
In the early
1770s John’s parents returned to England and settled in York. The young John
was sent to Edinburgh to a school for deaf children run by Thomas Braidwood. We
have little information about this part of his life; it is possible he learnt
to lip read and probably to speak as well. Sign language had not yet been
devised. In 1778 he was sent to the Warrington Academy, a famous Dissenting school
which had no special provisions for children with disabilities.
It was at
the Warrington Academy that he developed a great interest in mathematics, science
and astronomy. After three years he left Warrington to live in the Treasurer’s
House near York Minster, now in the keeping of The National Trust. It was here
that his astronomical career was to begin. His astronomical journal started on
November 16th 1781.
A year earlier a distant cousin had also moved
to York. Edward Pigott lived with his father Nathaniel in a house that survives
to this day as No. 33 Bootham. Edward and his father were both astronomers.
Together John
Goodricke and Edward Pigott forged a partnership that would push back the frontiers
of astronomy. Not only would they make
discoveries but like true scientists they would try to explain them, and their
five year partnership would make York one of the astronomical centres of the
world.
The two
astronomers came together in 1781, a few months after William Herschel
discovered the planet Uranus from his home in the city of Bath. The scientific
community was abuzz with all things astronomical. They must have seemed an odd
couple; Goodricke, a deaf youth of just 17, and his older cousin Pigott who,
having spent much of his life living in France, liked to dress in the
flamboyant French style.
The Pigott’s
observatory has been described as the third best private observatory in England,
while Goodricke observed from a room in the Treasurer’s House using a small
telescope.
Pigott and
Goodricke knew of a star in the constellation of Perseus called Algol, or Beta
Perseus. The constellation depicts Perseus holding the head of the Medusa. Algol marks the eye of the Medusa.
As far back
as 1669 astronomers had noticed something odd about this star. It is what we
refer to today as a variable star, because it varies in brightness. The world
Algol means ‘The Winking Demon’. Goodricke
observed the star and recorded that it remained at its brightest for 2 days, 20
hours, 45 minutes, and then faded away for about 10 hours before recovering again
to its normal brightness. Goodricke’s observations came very close to modern
estimates, even though he had only his eyes and a clock to work with.
As Goodricke
couldn’t hear the clock ticking, a servant beat out the seconds with a finger
so he could accurately work out the time. Goodricke was obsessed by precise
timing. When he was observing Algol from the Treasurer’s House and Pigott was
doing the same from his observatory in Bootham a few hundred metres away, he
worked out that if they used the chimes of the bells in York Minster, they
needed to allow for the extra time it took for the sound to reach Pigott.
Goodricke
and Pigott correctly deduced that there was another body orbiting Algol, causing
the light to vary. They believed that it could be a planet; we know today that
it was another star. Today astronomers find planets around other stars using
the principles put forward by Goodricke and Pigott. Their ideas were over two
hundred years ahead of their time.
John
Goodricke was only nineteen in 1783 when he wrote to the Royal Society about
his observations and thoughts on Algol. He
was deaf and unknown outside of York, but Edward Pigott moved in the right
circles and knew everyone of importance in astronomy. He contacted his friend the
Astronomer Royal Nevil Maskelyne and soon Goodricke’s work was published.
The effect
on the astronomical community was electrifying. All over the country people
were observing Algol and Goodricke was awarded the Copley medal by the Royal
Society, the highest award they could give.
Goodricke
and Pigott had made a remarkable contribution to variable star astronomy and this
was just the start of their endeavours.
September 10th
1784 would become a night to remember in York, with not just one but two new variable
stars being discovered. Goodricke found Beta Lyra in the constellation of Lyra
(the Lyre), while Pigott was discovering Eta Aquila in the constellation of
Aquila (the Eagle).
The
indefatigable Goodricke was to discover another variable star, Delta Cepheus in
the constellation of Cepheus (the King), on October 24th 1784. This star is of
immense importance today as it is a prototype for the Cepheid type variables
which are used to determine how far away galaxies are. Goodricke could never
know of the importance of this star to astronomy.
More reports
were sent to The Royal Society. Astronomers in London must have wondered what
on earth was going on in York!
Goodricke’s short
life was nearly over. He was made a fellow of the Royal Society; a most
prestigious honour for someone so young, but never knew about his election
because he died on April 20th 1786, two weeks before the letter arrived. He was
only twenty one, and observing the night sky in the very cold conditions of the
time probably contributed to his death from pneumonia.
Pigott moved
to the city of Bath where he continued observing the night sky and in 1795 he
discovered the variable stars R Corona Borealis and R Scutum. I have christened
Goodricke and Pigott ‘The Fathers of Variable Star Astronomy’.
