Sunspots can be so cold that water vapor ‘steam’ can even form within them! In 1995, astronomers Lloyd Wallace, William Livingston and Kenneth Hinkle at the National Solar Observatory in Tucson, Arizona worked with collaborators to obtain infrared spectra that proved that water molecules could exist in the umbral regions of some sunspots.
via NASA – Sunspots from A to B – solar magnetism
Water has been discovered on the surface of the sun in sunspots where it causes a sort of “stellar greenhouse effect” that affects the sunspot’s energy output.
“There’s a perception that the sun is too hot to form water on its surface, but we have proved that it exists in sunspots because they are cooler,” said Peter Bernath, a chemistry professor at the University of Waterloo.
Scientists from UW and the National Optical Astronomy Observatories in Tucson, Ariz., recorded evidence of water – – not in liquid form because the sun is too hot, but as vapor or steam — in dark sunspots.