This cartoon shows what happens to stars that are about the same size as the sun.
As they get older, the star gets bigger and redder and cooler. The outer gas layers of the star blow off in a high speed wind. We can see this gas for a long time from the Earth. It is called a planetary nebula.
The inner part of the star is left behind. We call it a white dwarf. It is very hot and very small compared to a star. Only about the size of the Earth.
But the matter that makes up the white dwarf is like nothing you've ever seen before. If you took a piece of the white dwarf about the size of a marble, it would weigh as much as the largest elephant at the zoo.
Let's explore three different black bodies. The curves on the left tell us the color and brightness (intensity) of light given off by an equal-sized piece of black bodies with temperatures of 4000 Kelvin (3727 degrees Celsius), 6000 Kelvin (5727 degrees Celsium) and 8000 Kelvin (7727 degrees Celsius). These temperatures are typical of stars.
The color of the curve tells the color the black body would appear to the eye. The rainbow below the curve shows the position of the visible light band (light we can see) with respect to the light given off by these black bodies. The first thing to notice is though the light from the black bodies peaks at wavelengths we can see, much of the light given off is at wavelengths above and below our visual range.
The hottest black body (8000 K) produces mostly blue light and a lot more of it than the cooler ones. The height of the curve tells us how much light.
The coolest black body (4000 K) produces mostly red light. It is so dim compared to the hottest (blue) black body that it hardly shows up on the plot.
How do we use this information ... continue on to find out.
Let's explore three different black bodies. The curves on the left tell us the color and brightness (intensity) of light given off by an equal-sized piece of black bodies with temperatures of 4000 Kelvin (3727 degrees Celsius), 6000 Kelvin (5727 degrees Celsium) and 8000 Kelvin (7727 degrees Celsius). These temperatures are typical of stars.
The color of the curve tells the color the black body would appear to the eye. The rainbow below the curve shows the position of the visible light band (light we can see) with respect to the light given off by these black bodies. The first thing to notice is though the light from the black bodies peaks at wavelengths we can see, much of the light given off is at wavelengths above and below our visual range.
The hottest black body (8000 K) produces mostly blue light and a lot more of it than the cooler ones. The height of the curve tells us how much light.
The coolest black body (4000 K) produces mostly red light. It is so dim compared to the hottest (blue) black body that it hardly shows up on the plot.
How do we use this information ... continue on to find out.
Last modified prior to September, 2000 by the Windows Team
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