From the wiki[0]: "It is believed to be the first compound to have formed in the universe"
They created the molecule under space conditions:
"The experiment was carried out at the Cryogenic Storage Ring (CSR) at the MPIK in Heidelberg — a globally unique instrument for investigating molecular and atomic reactions under space-like conditions [...] They found that, contrary to earlier predictions, the rate at which this reaction proceeds does not slow down with decreasing temperature [...] Since the concentrations of molecules such as HeH⁺ and molecular hydrogen (H2 or HD) played an important role in the formation of the first stars, this result brings us closer to solving the mystery of their formation."
They created the molecule under space conditions:
"The experiment was carried out at the Cryogenic Storage Ring (CSR) at the MPIK in Heidelberg — a globally unique instrument for investigating molecular and atomic reactions under space-like conditions [...] They found that, contrary to earlier predictions, the rate at which this reaction proceeds does not slow down with decreasing temperature [...] Since the concentrations of molecules such as HeH⁺ and molecular hydrogen (H2 or HD) played an important role in the formation of the first stars, this result brings us closer to solving the mystery of their formation."
[0]: https://en.wikipedia.org/wiki/Helium_hydride_ion#Interstella...