ALMOST 250 years ago, a young and profoundly deaf astronomer by the name of John Goodricke leaned out of a window at York's Treasurer's House and made a series of observations which helped change the way we understand the universe.

Goodricke, still a teenager, noticed that a star named Algol was slowly 'winking' - dimming then brightening again. He measured the period of the 'wink' - and his findings were reported to the Royal Society.

Goodricke subsequently observed two more 'variable stars' - β Lyrae and δ Cephei . They're a class of stars known today as 'Cepheid variables' . And by comparing how bright they are with how long it takes them to dim and then brighten again, astronomers can work out how far away they are - and so how big our universe is.

Goodricke was recognised in his day with the award of the Copley Medal and, in 1786 at the age of just 21, election to the Royal Society. Sadly, he died soon afterwards - possibly from a chill caught as a result of 'exposure to night air.'

But now, more than 230 years after his death, the brilliant young astronomer is to be recognised again - with a new York Civic Trust blue plaque.

An earlier bronze plaque was put up in 1952. But the Trust says that by today's standards the wording was 'inaccurate and disrespectful'. A group of anonymous donors raised funds for the Trust to commission a replacement, which will be unveiled tomorrow at Treasurer's House.

Civic Trust heritage officer Joshua Scarlett said Goodricke was remembered today not only for his discoveries in astronomy, but also as a pioneering figure in Deaf heritage. "There has been tremendous interest from deaf and hearing-impaired people about this new plaque to a real science superstar," he said.

The Trust will livestream the unveiling at 1pm tomorrow from Treasurer’s House. The event will be signed by British Sign Language in a Yorkshire first.