Hello Raul, outgassing I can understand, outgassing only in the direction away from the sun, I can't accept for several reasons. First of all, being on the side away from the sun, there is no heat buildup, therefore the surface on the side away from the sun is cold and stable. Also, on the side away from the sun, you should not be able to see anything even if thousands of tons of stuff were discarged you would not be able to see it until it moved out of the shadow cast by the comet. If the tail were made up of matter you should be able to see the shadow of the comet. since you can not see the shadow, the tail is not made up of matter.
If the tail is simple refraction of light, as I suspect, you would not see a shadow. Again, I refer back to the tail of light that apears on the back side of street lights in an Ice fog. If you were looking at fog crystals behind the light you would see the shadow cast by the shield above the street light.
Dan
Space/Science » in reply to Re: Comet Tails
Re: Comet Tails