Colonel Brian Duffy

Colonel Brian Duffy is a veteran of four space flights, he has logged a total of 40 days, 17 hours, 34 minutes and 59 seconds in space.  He was a pilot of two shuttle missions and the commander of another two.  Who better than to start this page.   I was lucky enough to ask my question in person to Colonel Duffy at Kennedy Space Centre.  

In weightless conditions convection, one of the three methods of heat transfer, cannot occur.   Have you ever noticed any effects of this in space?

Colonel Duffy gave two examples.   Firstly light bulbs don't last as long as they do on Earth.   With gravity the air surrounding the bulb is heated up and convects away the heat.   In weightless conditions this can't happen so the bulbs get far hotter, evaporating their filaments and reducing their lifespan.

Colonel Duffy's other example happened when he was having breakfast on the ceiling.   He reasoned that he would have to have breakfast on the floor for most of his life and should therefore take the opportunity for upside down dining whilst he had it.   On the other side of the cabin a crew member used an oven to heat up a snack.   A minute or more later Colonel Duffy got a shock, he was hit in the face by an invisible bubble of hot air.   When the crew member had grabbed his snack out of the oven he had also pulled out the hot air which had slowly moved across the cabin towards the unsuspecting astronaut.   The air was unable to rise up and spread out by convection as it would have done on Earth.