It was 1969 and Neil Armstrong had just become the first man to set foot on the moon.
The dome overlooks Mansfield
A space enthusiast placed a small advertisement in a local newspaper asking for people who were interested in astronomy.
A handful of men answered, resulting in the formation of the Mansfield and Sutton Astronomical Society.
More than 30 years later, the society now owns its very own observatory, overlooking Mansfield from one of the highest points in Nottinghamshire.
The domed Sherwood Observatory contains a 61cm mirror telescope, designed by retired car electrician Gordon Jones and built by society members.
The "home-made" telescope will take centre stage over the next week when people from far and wide visit to view Mars.
The so-called "Red Planet" will be making its closest pass to Earth in 60,000 years and National Astronomy Week has been timed to coincide with the phenomenon.
Observatories and astronomy groups across the world are hosting events to mark the occasion - although, at its closest, Mars will still be some 55,760,000km away on 27 August.
The Mansfield group is no exception. It is opening the observatory each night at 2100 BST, starting on Saturday.
People will be allowed to view Mars through various telescopes, including the huge Newtonian telescope in the observatory dome.
However Mr Jones, who acts as observatory director, warns people not to expect the spectacular views of Mars provided by interplanetary probes or the Hubble Space Telescope.
He says: "Unfortunately, Mars this time is fairly low in the sky, plus the fact there are a lot of dust storms taking place on Mars right now."
Being low in the sky means telescopes must look through more atmosphere, causing the image to distort, he says.
"The two factors combined are going to spoil the image a little."
Mr Jones says to expect a "fuzzy and blurry" image of Mars through telescopes.
WHERE TO LOOK (in the UK)
- Over the next week Mars rises in the SSE about 10pm
- Between midnight and 1am it should be due south
- It sets in the SSW about 5am
- It will be an orange light, brighter than stars
"But with a little luck we should see the polar caps, and perhaps a few dark areas."
Regardless, Mr Jones says he and the astronomy group's 60 members relish the chance to show off the observatory to the public.
"We are proud, every one of us, and there is nothing we like better then showing the general public around."
Recalling the lengthy construction process, Mr Jones says he broke down in tears when the original mirror, which he had ground by hand, was dropped and broken.
The telescope and dome, built between 1972 and 1986, sits on a block of land purchased for £50.
When not gazing into space, any visitor to the site has a breathtaking view over Mansfield.
"Many people say they would love to live up here," Mr Jones says.
However, the proximity to Mansfield can be a curse due to light pollution.