> Helium hydride (HeH), a combination of helium and hydrogen, was spotted some 3000 light-years from Earth by an instrument aboard the airborne Stratospheric O

> Helium hydride (HeH), a combination of helium and hydrogen, was spotted some 3000 light-years from Earth by an instrument aboard the airborne Stratospheric Observatory for Infrared Astronomy (SOFIA), a telescope built into a converted 747 jet that flies above the opaque parts of Earth’s atmosphere. Not quite. The paper makes it clear that what was actually observed was HeH+: > Here we report observations, based on advances in terahertz spectroscopy8,9 and a high-altitude observatory10, of the rotational ground-state transition of HeH+ at a wavelength of 149.1 micrometres in the planetary nebula NGC 7027. https://www.nature.com/articles/s41586-019-1090-x https://www.nature.com/articles/s41586-019-1090-x