We haven't travelled aboard for a while, but humans on Earth haven't set foot on one particular destination - the Moon for almost 50 years! Recently, to prepare for a return to the lunar surface, NASA finally opened a precious "souvenir" brought back to Earth by Apollo 17, the last manned mission to the Moon in 1972.

The Apollo astronauts collected segments of rocks and soil from the Moon's Taurus–Littrow Valley and then sealed the sample in a vacuum tube on the Moon before returning it to Earth. Of course, unboxing the preserved sample wasn't as simple as opening a packing bag! The tube didn't only contain soil and rock fragments. A small amount of volatiles that evaporates readily at normal temperatures might have been preserved together in the tube. The technology at the time wasn't advanced enough to fully study the sample so the tube was left unopened for nearly 50 years. With new technology developed as time progresses, specialised tools would be developed to minimise sample loss while opening the containers, and they would study the material in more advanced ways. This was finally done in 50 years' time. An "Apollo Can Opener" was specially designed by ESA's to puncture the sample tube and then capture gases as they escape.

Apart from the US's lunar returning Artemis missions, India, Japan, South Korea, and the UAE will also launch their probes to the Moon this year. It has been almost 50 years since the last human landed on the lunar surface. Unsealing the time capsule in 2022 is not only commemorating the historic missions, but analysing the sample will also be beneficial to future explorations.