Last month’s wonderful pre-dawn ballet of Mercury, Venus, Mars and Jupiter was at best difficult to see for most of us city dwellers.

If you would like to see a day by day simulation of the entire month of May’s celestial flash mob, google: “The four planet dance of 2011” (with quotes), which will get you to a Sky & Telescope article detailing the event.

Scroll to the bottom of the page and click on Click here to view a 700-kb movie and enjoy.

You will need to have Apple’s Quicktime to view the movie.

If you don’t have it, google: apple +quicktime to be directed to a download site. The program is free.

–Roger Linnett