Issued in 1973, this commemorative stamp from Grenada marks the 100th Anniversary of the World Meteorological Organization (WMO), founded in 1873. The dynamic design combines classical mythology and modern science, featuring Helios, the Sun god, driving his chariot above a diagram illustrating the Earth’s solstices and equinoxes around the Sun. The WMO emblem with centenary dates reinforces its international scientific significance. Printed in rich multicolour tones, this issue is sought after by collectors of meteorology, astronomy, UN agencies, and thematic science material, as well as Caribbean commemoratives.