How to Determine the Distance to Very Distant Galaxies

In 1909 a Lowell Observatory astronomer Naehvesto Slipper said about examining the quality of the light from the mysterious nebulae. The only telescope he had was a relatively modest 24 inch instrument. With no fancy electronic gizmos of the sort astronomers have today all observations had to be done by hand and eye. He laboured away night after night often in freezing conditions recording the results on film. In those days an astronomers lot was not a happy one. Yet the compulsion that drives the slippers of this world is that dedicated toil in some small corner of a subject can unexpectedly come. And that is just what happened at Lowell Observatory. By 1912 Slipper had assembled enough data