MS/MS in Space true OBSOLETE A tandem mass spectrometry method in which product ion spectra are recorded in m/z analyzers separated in space. Specific m/z separation functions are designed such that in one section of the instrument ions are selected, dissociated in an intermediate region, and the product ions are then transmitted to another analyser for m/z separation and data acquisition. MS:1000335 MS This child of the former purgatory term m/z Separation Method was made obsolete.