Infrared radiation is detected from the moon by Charles Piazzi Smyth from the peak of Guajara on Tenerife. He uses a thermocouple (a device which converts heat into electric current) to detect infrared light from the full moon. Piazzi also tests observations at different altitudes and shows that better observations are obtained at higher altitudes. This is the first indication that our atmosphere absorbs some of the infrared radiation from space.