[pytness]

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."

[0]: https://en.wikipedia.org/wiki/Helium_hydride_ion#Interstella...