Starlight is actually a mixture of all the colors of the rainbow, plus the wavelengths of light that our eyes can’t see, such as X-ray, ultraviolet, infrared, etc.

The color we perceive when we look at a star, for example the red of Antares or the blue of Rigel, merely means that it is that color that the star is sending the most of out into space.

So to answer your question, the answer is “yes.” It’s not only possible for a star to shine in different colors, all stars actually are shining in different colors. The giant star in the shoulder of Orion the Hunter, Betelgeuse, appears red because red is the wavelength of visible light it is sending the most of into space. Betelgeuse is also emitting light in blue, white and yellow wavelengths, but not as strongly it is in red.

A nice article on why stars have the colors they do can be found on the wonderful “Bad Astronomy” blog by Phil Plait. I recommend his blog entry “Why are there no green stars?” as a good place to find a more technical explanation of starlight.

The moon is “white” because it is reflecting sunlight. That’s not the same thing as “white hot.”

The temperature on the moon’s surface in sunlight is in fact a couple of hundred degrees Fahrenheit, but that’s nowhere near the several thousand degree temperature of the sun’s photosphere (the part of the sun that emits the light we see).

Is a red rose as hot as a red-hot fireplace poker? Of course not.

You can know the difference between reflected light from a rose and emitted light from a red-hot poker by studying the spectrum of light from the object in question. The same applies to the surface of the moon and stars.

You may post this, I would just like to know.

I take long daily morning hikes, usually starting off in the dark, so I often observe the moon and the early morning sun at the same time. It has always bothered me that if I note the position of the moon’s shadow and then draw an imaginary line to where the sun “ought” to be, it’s not there! Never!

In trying to explain this to myself, I can think of two reasons. First, there must be some light refraction caused by the atmosphere particularly when the sun or the moon is low in the sky. Second, visible light from the sun left its source earlier than simultaneously observed light from the moon; and meanwhile, sun, earth and moon have been in motion relative to each other.

Are these ideas sufficiently explanatory, or am I missing something?

Roger Vance