Some tubes were kept sealed for all that time so that they could be studied years later.
NASA knew "science and technology would evolve and allow scientists to study the material in new ways to address new questions in the future," said Lori Glaze, director of the Planetary Science Division at NASA Headquarters.
The sample in question designated - 73001 - was collected by astronauts Eugene Cernan and Harrison Schmitt during the Apollo 17 mission in December 1972 - the last mission of the program.
To collect the rocks, a 35 cm tube and 4 cm wide tube had been hammered into the ground of Taurus-Littrow valley on the Moon.
Only two samples on the moon were vacuum sealed, and this is the first to be opened.
Possibly containing gases or even volatile substances (water, carbon dioxide, etc.).
And the aim is to extract these gases, which are probably only present in very small quantities, to be able to analyse them using spectrometry techniques that have become extremely precise in recent years.
In early February, the outer protective tube was first removed.
It was not itself revealed to contain any lunar gas, indicating that the sample it contained remained sealed.
Then on February 23, scientists began a weeks-long process aimed at piercing the main tube and harvesting the gas contained inside.
In the spring, the rock will then be carefully extracted and broken up so that it can be studied by different scientific teams.
The extraction site of this sample is particularly interesting because it is on the site of a landslide.
"Now we don't have rain on the Moon," said Juliane Gross, deputy Apollo curator. "And so we don't quite understand how landslides happen on the Moon."
According to Gross, researchers hope to study the sample to figure out what causes landslides.
Only three lunar samples will remain sealed after 73001. When will they in turn be opened?
"I doubt we'll wait another 50 years," said senior curator Ryan Zeigler.
"Particularly once they get Artemis samples back, it might be nice to do a direct comparison in real time between whatever's coming back from Artemis, and with one of these remaining unopened core, sealed cores," he said.
Artemis is NASA's next moon mission; the agency wants to send humans back to the Moon in 2025.
Large amounts of gas should then be collected, and the experiment currently being conducted helps to better prepare for it.