Ptolemy or optical factors and those caused by judgmental factors. He offered an obscure explanation of the sun or moon illusion (the enlarged apparent size on the horizon) based on the difficulty of looking upwards. There are several characters or items named after Ptolemy, including: [[File:Ptolemaeus - Quadripartitum, 1622 - 4658973.tif|thumb|"Quadripartitum", 1622]] [[Category:Ptolemy| ]] [[Category:100 births]] [[Category:170 deaths]] [[Category:1st-century Romans]] [[Category:2nd-century Romans]] [[Category:2nd-century philosophers]] [[Category:2nd-century poets]] [[Category:Egyptian calendar]] [[Category:Ancient Greek astrologers]] [[Category:Ancient Greek astronomers]] [[Category:Ancient Greek mathematicians]] [[Category:Ancient Greek music theorists]] [[Category:Astrological writers]] [[Category:Claudii]] [[Category:Egyptian astronomers]] [[Category:Egyptian mathematicians]] [[Category:Epigrammatists of the Greek Anthology]] [[Category:2nd-century people of Roman Egypt]] [[Category:Ancient Greek geographers]]
Mount Ptolemy (Antarctica) fixing positions on the Earth's surface. Mount Ptolemy (Antarctica) Mount Ptolemy () is an isolated block mountain with four main summits, the highest rising to 1,370 meters. It lies close north of the Traffic Circle on the northwestern side of Mercator Ice Piedmont, Antarctic Peninsula. First observed by Finn Ronne and Carl Eklund of the U.S. Antarctic Service, 1939–41, from their sledge route through the Traffic Circle. Surveyed by Falkland Islands Dependencies Survey (FIDS) in 1947. Named by United Kingdom Antarctic Place-Names Committee (UK-APC) after Claudius Ptolemy (2nd century AD), Egyptian mathematician, astronomer and geographer, who introduced the system of