In September 2010, Venus will shine brilliantly in the western sky. Its size and phase will change dramatically as it `catches up' with the Earth.
This table provides simulated images and other data for Venus every Tuesday it is visible. Each date links to an image showing how Venus will look that day. The altitude column gives the angle between Venus and the horizon as seen from Honolulu at 19:00 HT (7:00 pm); each number is also a link to a map of the sky. Venus will be setting in the west; to get the best views of the planet, we need to observe it as early in the evening as possible. The diameter column gives the apparent diameter of the planet; note the rapid increase in size as Venus approaches the Earth. Finally, the phase column gives the angle between our line of sight toward Venus and the direction of sunlight falling on the planet. At the start of the semester, Venus is half-full, but a month later it will be a thin crescent.
Animation showing Venus as seen from the Earth from 31-Jul-2010 at 14:00 to 31-Oct-2010 at 14:00 HST (01-Aug-2010 at 00:00 to 31-Oct-2010 at 20:00 UT). Note the planet's dramatic change in apparent size and phase as it catches up with the Earth. Generated using Solar System Simulator (Courtesy NASA/JPL-Caltech).
Video clip showing Venus taken on 03-Oct-2010 at 15:00 HST. Gives a pretty good impression of how Venus looks in a small telescope on a windy afternoon.
Images of Venus taken every weekend from 26-Sep-2010 through 24-Oct-2010. Compare these images with the `Venus Approaching' animation above.
Resources for amateur and professional observers. Has links to ongoing observing projects.
Joshua E. Barnes
(barnes at ifa.hawaii.edu)
24 October 2010