Königsberg Observatory (left) where Friedrich Wilhelm Bessel made the first successful distance measurement to a star other than the Sun ( Credit : Wikipedia).  The Gaia satellite (right) which has determined the distance to millions of stars to high degree of accuracy ( Credit : ESA/ATG medialab; background: ESO/S. Brunier).  By Dirk Goës BSc(CompSc) UOW, MSc(Astronomy) Swinburne The observation phase of the European Space Agencies (ESA) groundbreaking Gaia mission ended on

A short explanation An image from a video visualisation of the expanding and accelerating universe ( Credit : NASA's Goddard Space Flight Center Conceptual Image Lab).  By Dirk Goës  BSc(CompSc) UOW, MSc(Astronomy) Swinburne About me: I have been a member of the Sydney City Skywatchers for two years.  I am a member of the committee and am responsible for maintaining and improving the Skywatchers website.  I recently graduated with a Master of Science (Astronomy) from Swinburn