Why do things glow green in the dark?

I'm sorry if I sound stupid, but why can't 'glow in the dark' phosphorescence items glow blue or red or even white? Do they and I just happen to not know? What properties and fun experiments can I use and practice to make these things?
I appreciate your help.

2010-09-29T18:03:08Z

AlisonM ; Thank you for being the only helpful answer. Most other answerers aren't understanding what I was asking : /

But now I wish to know where I can get the glowing material for this so I can make it?

AlisonM2010-09-29T01:38:28Z

Favorite Answer

Glow sticks are not phosphorescent - their glow results from a chemical reaction not the absorption of light. However, according to wikipedia phosphorescent things do come in red and blue as well as green. I guess maybe the green stuff is just cheaper and less toxic than the rest!

http://en.wikipedia.org/wiki/Phosphorescence

Anonymous2010-09-29T07:16:30Z

They can glow different colors. I've seen blue, green, and red glow sticks. I think green is most common because the human eye can differentiate more shades of green than any other color (why night vision is in green).

?2010-09-29T07:15:58Z

Things can glow red, yellow and blue. Have you never been to a rave?

And you best answer for this is just to google it. or hope theres a science teacher online

eragon1man2010-09-29T07:15:41Z

you mean you havent heard the legend of the green monster of space? he only comes out in the dark and takes over the entity of an object with its green slime... watch out... it is said to be highly contagious slime so if youre holding something that glows green in the dark... drop before you turn green yourself!

jenisisgrafix2010-09-29T07:14:35Z

the ink form any highlighter (no matter the color) glows in the dark. also lemon juice does too.