Be Prepared for the Transit of Venus: June 5, 2012

June 2012  :  Dave Huestis

This notice is a brief reminder about the rare transit of Venus that will be visible here on the evening of June 5. A more detailed account appeared last month, which can also be viewed at the Skyscrapers website (http://www.theskyscrapers.org). Following are the highlights of this event, the last one to occur until the year 2117.

Local circumstances calculated for Providence, Rhode Island:

  • June 5, 2012
  • Transit begins at 6:03:32 pm EDT — this event is called first contact when the disk of Venus will begin to encroach upon the Sun’s top left edge
  • Venus will continue to move “onto” onto the solar disk and its dark image will become silhouetted against the Sun
  • At 6:21:22 pm EDT, Venus will be entirely in front of the solar disk — this event is called second contact.
  • At this time the “black drop” effect can be observed with a telescope (a portion of Venus’ dark disk will seem like it is dripping towards the solar limb, or edge, like a teardrop)
  • Within a few seconds the effect will vanish
  • The transit’s progress will continue locally through sunset at around 8:17 pm EDT
  • Choose an appropriate site with an unobstructed western view to maximize your observation

How to safely observe:

  • When observing the Sun, observe caution as well
  • Do not stare at the Sun even while it is setting — ultraviolet and infrared can still damage one’s eyes
  • If you’ve never done any telescopic solar observing prior to this day, don’t start now
  • Only experienced observers using the proper methods or filters should be observing the Sun
  • Non-telescope methods — #14 welder’s glass or special solar eclipse glasses are safe to use
  • Do not use the eclipse glasses to look through a telescope — the concentrated sunlight will burn a hole through them instantly and severely damage your eye
  • Don’t use small glass or plastic filters that usually come with the small department store refractors — they can shatter (and have done so)
  • Do not use exposed film of any kind 
  • Don’t stare at the Sun even with sunglasses
  • Don’t risk your eyesight due to an oversight

Ladd Observatory in Providence and Frosty Drew Observatory in Charlestown  will be hosting transit of Venus observing sessions. Visit their websites for details, and cross your fingers for some clear skies. You won’t be able to wait around until the next one!