At the moment, the earth-observation satellites which employ microwaves generally use short-wavelength radiation, because this provides more detailed images.
The new map is a smart byproduct of the European Space Agency (Esa) telescope's main mission which is to survey the Cosmic Microwave Background, or CMB - a pervasive but faint glow of long-wavelength radiation that comes to us from the very edge of the observable Universe.
The trick is to use metamaterials: materials that owe their characteristics to features of their structure that are smaller than the wavelength of the electromagnetic radiation.
Vitamin D is incorporated in the body when skin is exposed to sunlight of a certain wavelength but in the UK, during winter months, UV-B radiation can be insufficient to properly support vitamin D synthesis in the body.