Onboard Nimbus 7, the TOMS instrument provided nearly fifteen years of reliable, global ozone maps.  This coverage is still being provided today by other TOMS instruments which highlights the international interest in monitoring global ozone trends. HALOE and GOME are other instruments which obtain global ozone profiles.  Unlike TOMS, which uses individual spectral signatures to measure ozone, these identify absorption features within selected spectral bands through a solar occultation technique (HALOE), and scattering and DOAS techniques (GOME). All of these missions exclude the polar night.