  Fundamental changes are taking place in the way we do astronomy. In twenty
years time, it is likely that most astronomers will never go near a
cutting-edge telescope, which will be much more efficiently operated in service
mode. They will rarely analyse data, since all the leading-edge telescopes will
have pipeline processors. And rather than competing to observe a particularly
interesting object, astronomers will more commonly group together in large
consortia to observe massive chunks of the sky in carefully designed surveys,
generating petabytes of data daily.
  We can imagine that astronomical productivity will be higher than at any
previous time. PhD students will mine enormous survey databases using
sophisticated tools, cross-correlating different wavelength data over vast
areas, and producing front-line astronomy results within months of starting
their PhD. The expertise that now goes into planning an observation will
instead be devoted to planning a foray into the databases. In effect, people
will plan observations to use the Virtual Observatory. Here I examine the
process of astronomical discovery, take a crystal ball to see how it might
change over the next twenty years, and identify further opportunities for the
future, as well as identifying pitfalls against which we must remain vigilant.
