"Wyoming Stars" and "Midnight on the Rubicon":

For those of you interested in the technical aspects of this picture, it was created as follows:  First, I was traveling light, so regrettably I didn't bring my tripod. Because of this and because of the nature of time exposures, I had to build a tall stack of rocks on which to place the camera. The good thing about this was that I could hide the camera under the rocks to prevent theft during the night. I chose to shoot using a 20mm wide angle lens, and just managed to get both my campfire and truck in the shot. After opening the shutter (20mm f3.5, Provia 100 Slide) I then threw rocks at my campfire to excite sparks and flames while keeping me out of the exposing picture. I also used a small high-efficiency LED flashlight to emphasize certain areas of the photo (such as the Blazer and undercarriage and tires) by hiding behind a small bush for 30 seconds or so while pointing the light towards the target without getting in the shot myself. Hence the "invisible" light sources you might notice. As the camera exposed during the night, the stars did what stars do, and slowly moved around the earth (some argue that the Earth is actually revolving, but clearly they don't understand). These revolving stars create the interesting twisty thing in the sky.

Much to my horror, when I retrieved my camera in the morning, after exposing for about 6 hours, the whole camera and lens had a thick coating of ice over it. There evidently was a heavy frost that night, and the lens was completely obscured by ice. I was afraid the picture (or even the camera/lens) would be ruined, but instead, it merely created a little haze on the mountainside, and cool star trails that get dimmer and more diffuse as they twist. Because it was extremely cold, no moisture got inside the camera or lens, and the camera was easily dried off.  Note: There are no touch-ups on this photo.

Q:  Okay, so stars revolve around the Earth, but why are some of them blue, and others yellowish?

A:  I was amazed by the colors as well.  The amazing thing is that in the full size non-jpeg version of this pic, the colors are even more astounding and brilliant.  I have two theories as to what might cause it, and I suspect the real answer is a hybrid of the two (hopefully for humanity's sake, the second theory is more significant!).

Theory number one assumes that all stars are approximately the same color, and that as an object moves towards or away from the earth it causes a frequency shift in the light given by Observedfrequency=SpeedOfLight/((SpeedOfLight-ApproachVelocity) X ActualFrequency). Therefore, if a yellow star(600nm) appears blueish(550nm), it must be traveling towards us at about one tenth the speed of light, or 30,000,000 meters per second. Luckily, since Alpha Centauri (the nearest star system) is 4.3 light years from earth, even if it is one of the blue-shifted systems, and even if it is aimed just right, we still have at least 43 years before it will actually strike the earth at its given maximum speed of approach.  However, I wrote this over a year ago, so we may have less than 42 years left!  Hopefully Alpha Centauri is red-shifted and will just fly off into space where it belongs!

Theory number two is based on the assumption that Alpha Centauri will not strike the earth in 42 years, that stars and galaxies are not moving towards or away from the earth at great enough speeds to cause a visible color shift, and that stars simply have different burning temperatures. Yellow stars are running cooler, blue stars are running hotter...

Michael

Jim offers yet another perspective on the number of years remaining before oblivion:

Hi Michael,
Your second theory is the significant one. Both theories are correct, and all stars are red-shifted, in proportion to their distance (because the universe is spreading apart), but that effect is far less significant than the different temperatures of stars. Blue stars are whiter and red stars are cooler. Our nearest star (the one that would have foiled your picture had you not gotten up early that morning) just happens to be in the middle of the range - and white as a result. (Then again, I imagine if we evolved under another star, our perception of white would probably be shifted accordingly.) The thing that surprised me about your picture is that the colors are so well defined. I've looked at the stars plenty - but I haven't been able to make out the colors as well as in your picture, and most photos of the stars show them as white. Remember the film you used for that one!  (Editor's note: Provia 100 35mm Slide film, 20mm f3.5 for 6 hours.)
Jim Scarborough KE4ROH
jims@iname.com http://fly.hiwaay.net/~jimes

Renaud offers yet more insight into this seemingly inexplicable phenomena:

The reason for the difference in star color is that stars have different temperatures. Many stars (including the Sun) are yellow. Some are red (very old stars; cooler than ours), others are blue (very young and hot stars).  (Editor's Note: I prefer the young hot ones...)
Renaud Fortuner
http://perso.wanadoo.fr/renaud.fortuner/vitae1.html

Jon offers the "Big Drain" theory:

Really like "Wyoming Stars!". Oh, by the way, the earth is flat and the stars just spin around as they fall into that big drain...
Jon
vze249jf@verizon.net

John offers this feedback:

Your theory about star colours is not correct. Stars have a large range of colours which depends on, amongst other things age, size and chemical composition. A "Red Dwarf" is called this for its colour. You cannot tell the speed at which a light source is moving by looking at its colour because as the colours 'shift', new colours are 'shifted' into those colours etc etc. To determine 'colour shift', you have to break the light into a spectrum (using a spectrometer) then look for specific emission lines in the spectrum and see how much they have moved relative to a reference source.
John Pennifold
john.pennifold@capgemini.co.uk