37.5 technology – named for the optimal human body core temperature (in celsius) and the optimal relative humidity level (by %) – uses active particle technology to maintain a desirable microclimate next to the wearer’s skin. Using activated carbon sourced from coconut shells and volcanic sand, 37.5 has an array of apparel partners, including Adidas and Asics, not to mention the US military – and now ESA’s Couture in Orbit. Founder and Chief Technology Officer Dr Gregory Haggquist tells his story.