DOWNLOAD ORION'S FREE SOLAR ECLIPSE VIEWER'S GUIDE

Cart
0

{"closeOnBackgroundClick":true,"bindings":{"bind0":{"fn":"function(){$.fnProxy(arguments,\'#headerOverlay\',OverlayWidget.show,\'OverlayWidget.show\');}","type":"quicklookselected","element":".ql-thumbnail .Quicklook .trigger"}},"effectOnShowSpeed":"1200","dragByBody":false,"dragByHandle":true,"effectOnHide":"fade","effectOnShow":"fade","cssSelector":"ql-thumbnail","effectOnHideSpeed":"1200","allowOffScreenOverlay":false,"effectOnShowOptions":"{}","effectOnHideOptions":"{}","widgetClass":"OverlayWidget","captureClicks":true,"onScreenPadding":10}

 224 of 263 
Constellation In Focus: Cassiopeia
Constellation In Focus: Cassiopeia

Cassiopeia is one of the easiest constellations to spot during the autumn and winter months; its big "W" shape rotates overhead each night. Apart from being a generally pretty area to scan in binoculars, there are some terrific sights to pick out.

9,000 light years away sits NGC 457, a 6th-mag open cluster known as the Owl Cluster. NGC 559 a 9.5-mag open cluster is about 2.5° from NGC 663 a 7th-mag open cluster seen in binoculars.

Cassiopeia is also the area of sky where Tycho's Supernova of 1572 appeared slightly to the west of Kappa Cassiopeiae, changing the appearance of the sky for six months and cementing Copernicus' 1543 rebuttal of Ptolemaic theory; in that year Copernicus died and his great work De revolutionibus orbium coelestium was published, overturning the established doctrine that the Earth was at the center of the universe. Unfortunately, nothing is visible to amateur astronomers but the site is of obvious historic interest.

December 2005

Details
Date Taken: 05/24/2011
Author: Sean O'Dwyer
Category: Astronomy

{"closeOnBackgroundClick":true,"bindings":{"bind1":{"fn":"function(event, startIndex, itemCount, newItems) { QuickLookWidget.assignEvents(newItems); $(\".Quicklook > .trigger\", newItems).bind(\"quicklookselected\", function(event, source, x, y) { OverlayWidget.show(\'#_widget1717944363040\', event, source, x, y); }); }","type":"itemsloaded","element":".PagedDataSetFilmstripLoader > .trigger"},"bind0":{"fn":"function(){$.fnProxy(arguments,\'#_widget1717944363040\',OverlayWidget.show,\'OverlayWidget.show\');}","type":"quicklookselected","element":".Quicklook > .trigger"}},"effectOnShowSpeed":"","dragByBody":false,"dragByHandle":true,"effectOnHide":"fade","effectOnShow":"fade","cssSelector":"ql-category","effectOnHideSpeed":"1200","allowOffScreenOverlay":false,"effectOnShowOptions":"{}","effectOnHideOptions":"{}","widgetClass":"OverlayWidget","captureClicks":true,"onScreenPadding":10}