Sidereus Nuncius
The first telescopes appeared in the Netherlands in 1608 when Middelburg spectacle-maker Hans Lippershey tried to obtain a patent on one. By 1609 Galileo had heard about it and built his own improved version. He probably was not the first person to aim the new invention at the night sky but his was the first systematic (and published) study of celestial bodies using one. One of Galileo's first telescopes had 8x to 10x linear magnification and was made out of lenses that he had ground himself. This was increased to 20x linear magnification in the improved telescope he used to make the observations in "Sidereus Nuncius".
Charles Husband
Husband worked with Bernard Lovell – the founder of the Jodrell Bank Observatory near Holmes Chapel in Cheshire – on the design and construction of the observatory's first large steerable radio telescope, the "250-ft telescope" (now known as the Lovell Telescope). After attempting to adapt military radar equipment to detect cosmic rays shortly after the Second World War, Lovell had realised that a much larger aerial would be required, and constructed a 66-metre diameter dish, limited by being static, before proposing the development of an even larger steerable telescope. The idea posed such formidable engineering challenges that the project had been declared "impossible" by other engineers, but Husband is reported to have concluded at their first meeting in September 1949, "It should be easy—about the same problem as throwing a swing bridge over the Thames at Westminster."