The cheese 'space' flight bid was made to mark the 40th anniversary of the Moon landing
Members of a Somerset-based cheesemakers group hoping to make the first space flight by a piece of Cheddar say they have lost track of it.
At 0400 BST a weather balloon was launched 18.6 miles (30km) into the upper atmosphere, carrying a capsule containing a 300g wedge of Cheddar.
But the organisers' GPS tracking system has stopped working and now they need help to find the cheese once it lands.
They say it could land anywhere between Pewsey in Wiltshire and Hertfordshire.
Dom Lane, of Shepton Mallet's West Country Farmhouse Cheesemakers group, told BBC Wiltshire: "We've been tracking the trajectory and the current prediction is that it could land anywhere from here in Wiltshire to Hemel Hempstead.
"The GPS isn't coming through on the web so we might need listeners' help to find it because we're not sure where it is at the moment."
It was expected that the balloon would burst at the edge of space, leaving the capsule to float back to the ground on a parachute.
The bizarre mission is to mark the 40th anniversary of the Moon landings.
In 2007 the group used a webcam to allow internet users to watch a traditional round of Cheddar mature live on the web over the course of a year.
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