Artificial circumzenithal and circumhorizontal arcs
  We revisit a water glass experiment often used to demonstrate a rainbow. On a closer look, it also turns out to be a rather close analogy of a different kind of atmospheric optics phenomenon altogether: The geometry may be used to faithfully reproduce the circumzenithal and the circumhorizontal halos, providing a missing practical demonstration experiment for those beautiful and common natural ice halo displays. 
Markus Selmke, Sarah Selmke
physics.ao-ph physics.optics