DR RAY CLARK & MERVYN GOFF / SCIENCE PHOTO LIBRARY. DR RAY CLARK & MERVYN GOFF / SCIENCE PHOTO LIBRARY.
Thermograph of a bunsen burner flame, showing variation in temperature throughout. Colour coding (see bar at bottom) ranges from blue (coldest regions) through green & yellow to red (hottest region). The hottest parts of the flame are seen in centre (red & yellow), with flame temperature decreasing towards the edges. The cooler green "spike" above the burner's nozzle (base of flame) indicates the stream of unburnt gas (ie methane) entering the flame.
Model release not required. Property release not required.