Using wget within perl

I want to wget several image files from a server at a time with the
same format. So, I am trying to write a perl script which calls wget
continuously, but with diffferent values of the variables. However,
when I use a system( "$foo")call, with $foo as the string with
variables, it doesn't seem to work, while if the wget command is used
at the terminal, it works just fine... Could anyone throw some light
on this matter?...The code is given below for reference...



#!/usr/bin/perl


$single = "http://casjobs.sdss.org/ImgCutoutDR6/getjpeg.aspx?
ra=18.87667&dec=-0.86083&scale=0.39612&width=400&height=400&opt=GST&query=SR(10,20)";

  system( "wget $single ")



After running this, I get the following error


sh: -c: line 0: syntax error near unexpected token `('
sh: -c: line 0: `wget
http://casjobs.sdss.org/ImgCutoutDR6/getjpeg.aspx?ra=18.87667&dec=-0.86083&scale=0.39612&width=400&height=400&opt=GST&query=SR(10,20)
'