posted on Dec, 18 2010 @ 12:05 AM
Originally posted by realeyes
But that says it's a new feature, the battery powered heater in the gloves. What about the first model? No one lost any fingers to frostbite? The
first photo just looks like an long cuffed heavy duty work glove. The second looks more like it belongs with the suit, Notice how thick the gloves
fingers are compared to the guys fingers. Looks like something I wear to hunt when it's 8 degrees out and my hands still freeze. Isn't space around
-300 or something like that?
That first photo is the same kind of glove in the second, I assure you.
Astronaut Michael E. Fossum, STS-121 mission specialist, inspects Reinforced Carbon-Carbon (RCC) Detailed Test Objective (DTO) box hardware during
a training session at Johnson Space Center. Fossum used a glove from a training version of the Extravehicular Mobility Unit (EMU) spacesuit.
Yeah, the heater is (relatively) new, added for comfort during the long spacewalks involved in space station construction. Temperature doesn't work
quite the same in a vacuum as it does here on the surface of the Earth. There are three methods of heat transfer: convection, conduction, and
radiation. Convection is when heat is transfered from an object to a gas or fluid in contact with it. This is primarily how a radiator in your house
heats the air. Air moves over the hot radiator and becomes warmer, moving on and making room for new, colder air to move in and be heated. Obviously
that's not a factor in the vacuum of space. Conduction is when heat is transfered from an object to another solid object in direct contact, without
movement of the medium as in convection. Like if you hold the end of a metal rod and put the other end in a flame, you will eventually get burned as
the heat conducts along the rod. Again, not a big problem in space as the suits and gloves are well insulated, preventing direct contact between the
occupant and other objects. Finally, radiation is when heat is transfered by electromagnetic waves. When items are heated, they emit photons in the
infrared range. When these photons impact an object, the energy is transfer to the object in the form of heat. This is how the sun heats the earth,
and is the type of heat transfer that must be dealt with in space. It is also the most inefficient method of transferring heat (which is why your
double-walled thermos with a vacuum between the walls can keep your coffee so hot for so long).
Any object above absolute zero emits infrared radiation. In the shade in space, it won't be receiving any substantial incoming infrared radiation
from the sun, so as it continues to emit it's own radiation, it will cool down. In the sun, it will be receiving copious amounts of infrared
radiation from the sun, so it will heat up. But the insulation on the suits will slow both the rate at which the heat is lost and gained. Since
radiation is all they have to worry about, it's not like submerging your gloved hand in liquid nitrogen, since there you will be dealing with
Inside the suit, the temperature is well regulated. And the gloves do have some air bladder space to allow circulation of the regulated air inside
the suit. So while the models without the battery heaters might have resulted in some cold, achey hands, it wouldn't be enough to cause any
edit on 18-12-2010 by nataylor because: (no reason given)