A blue stat has a temperature many times greater than a red star, but the temperatures of the transparent gasses in glowing advertising signs are about the same, whether they emit red or blue light, Please Explain this.
2006-10-16 22:28:09 · 4 answers · asked by jun 1 in Science & Mathematics ➔ Astronomy & Space
Blue stars and red stars have vastly different temperatures, but essentially the same composition (hydrogen with a bit of helium in the outer layers), so their color is a function of the black body emission.
Advertising signs on the other had, have gas that is different in composition: neon glows reddish when excited by electricity, while argon glows blue; in this case it is not a function of the temperature, but of the composition. In some cases, a phosphor coating -- similar to the one used in color TV -- is added inside a tube so as to produce other colors, again not a function of the temperature, but of the composition.
2006-10-16 23:51:59 · answer #1 · answered by Vincent G 7 · 3⤊ 0⤋
The Star is simply hot and radiating a continuous spectrum that depends on its temperature in a way called black body radiation.
An incandescent lamp works the same way. If the lamp voltage is too low, the light is “warmer” or more red than usual.
Fluorescent lamps are different. The gas in fluorescent lamps actually is at a much higher temperature than the Sun's surface, but the gas is so thin that there isn't much heat. That is because temperature is energy per molecule but the total heat is related to the number of molecules, and there aren't so many in the lamp. Anyway, the hot plasma (electrically charged gas) in the lamp actually radiates ultraviolet light which hits phosphors that coat the inside of the glass tube and causes them to glow in different colors that are determined by the chemical makeup of the phosphor.
2006-10-17 10:24:41 · answer #2 · answered by campbelp2002 7 · 0⤊ 0⤋
The blue star is a main sequence star. The red star is probably not a main sequence star. The blue star is hotter and the red star is cooler. The blue star is a larger than average (larger than the sun) main sequence star. The red star is much larger than it was when it was younger, but you can't know if it is bigger or smaller or more massive or less massive than the blue star based just on color. If you knew that the two stars were the same age, then you could use that fact to determine that the red star is at least a bit more massive than the blue star.
2006-10-17 08:07:44 · answer #3 · answered by hkyboy96 5 · 0⤊ 0⤋
I can't explain it, sorry!!!!!!!!!!
2006-10-17 08:39:23 · answer #4 · answered by jeff g 4 · 0⤊ 1⤋