How many Astronomers does it take to change a light bulb? 1). Ten. One to change the bulb, and nine to argue how their own bulb gives better colour. 2). None. Astronomers aren't afraid of the dark!. 3). Two: one to change the bulb, the other to complain about the light pollution. 4). Only one, but you have to go to Hawaii to get the really good bulbs. 5). Three, plus or minus seventy-five. 6). 10^8, because astronomers love really big numbers ! 7). None, they wouldn't change it because it ruins their night vision. And finally, 8): Eight: 1 observational astronomer to measure luminosity and redshift of bulb 1 theoretical astronomer to calculate spherical co-ordinates of bulb 1 departmental head to write to PPARC, for project funds 1 astronomical engineer to design and build the bulb replacing satellite 1 starling SIG programmer to write satellite control and data reduction software 1 NASA mission control expert to arrange satellite launch and say "t-2 go for main engine start........" etc 1 remote observer to manipulate the satellites arm once in elliptical orbit around light bulb 1 Grad student to act as scapegoat in event of mission failure.