StartsWithABang (3485481) writes "From a true dark-sky site, the kind that was available to all of humanity for the first 200,000 years or so of our species' existence, the human eye can discern tens of thousands of stars, detailed features of the Milky Way and a handful of deep-sky nebulae. With the advent of the telescope, our reach into the Universe was greatly enhanced, as the increase in light-gathering power opened up orders of magnitude more stars and nebulae, and even allowed us to see a spiral structure to some nebulae beginning in the 1840s. But in all the time since then, the largest telescope ever developed is not even six times bigger than the largest from nearly 200 years ago. Yet the details we can observe in the Universe today aren't limited by what our eyes can perceive looking through our telescopes at all. The combination of astronomy and photography has changed our understanding of the Universe forever, and we owe the greatest advances to an 'amateur' you've probably never heard of: Isaac Roberts."