The two GHOST spectra

This mosaic shows the two GHOST spectra of HD 222925, a remarkably bright, chemically complex star. This star is a prime example of the type of object that GHOST will investigate. 

The two GHOST spectra shown here, which were produced in the same single observation, measure light from around 350 nm to around 1015 nm. Light that is ‘bluer’ than 380 nm is ultraviolet and is invisible to our eyes. Light that is ‘redder’ than around 750 nm is infrared and is also invisible to our eyes. The dark lines in the rainbow are like the fingerprints of the gasses present in the star, including hydrogen, calcium, iron and gold. See this image comparison to see the most prominent features labeled.