Q&A: X-ray Astronomy
Yes. The ability of the transmission gratings on Chandra to make
fine distinctions between the energies of the X-rays from an
object makes it possible to identify sharp peaks or lines in the
spectrum due to ions of oxygen, silicon, iron, etc. if they are
present. By comparing the observed energy or wavelength of these
peaks with the corresponding values observed in the laboratory,
the red shift can be measured.