Occultation of Venus

Monday 18th June 2007

After the Sun and Moon, Venus, as I'm sure you know, is the third brightest natural celestial object in the entire sky (unless a nearby supernova were to go off!). So unlike the recent difficult daylight occultation of Saturn, on May 22, you will have a much better chance with this event which takes place on Monday, June 18, due to the brilliancy of Venus (m(v) -4.0). The Moon at the time of the occultation is a 3.7-day-old waxing crescent, and Venus itself presents a broader crescent showing a phase of 0.44. Venus at the time is just a couple of weeks past its greatest elongation east of the Sun, and lies some 45° away from the latter; therefore sunlight will not be a problem. Neither will it be a danger, because of the angular separation distance noted above. This event can be observed with the naked eye, given a clear, transparent sky, but binoculars are obviously better. With a high magnification binocular, you may just possibly be able to detect the planet's phase, if the binoculars are firmly fixed and well focused. Incidentally, if you have never seen Venus with the naked eye in daylight before, now is your chance to do so. The Moon will help you! Simply find the Moon, quite easy to do in a clear sky, and look just two "Moon widths" (1°) to the lower left of the crescent at around lunchtime on the 18th. With any telescope, of course, the occultation will be truly spectacular against the daylight sky!

Disappearance

Reappearance

The following table lists the times of disappearance of the planet at the Moon's dark limb (DD), and the reappearance at the bright limb, in the vicinity of Mare Smythii, near the Moon's eastern limb (RB). The table lists 14 UK cities, one of which should be near you. Don't forget to add an hour to the times given in order to obtain the local time of each event. If you want more detailed information, specifically for your location, do drop me an e-mail specifying where you live. Any observation reports, timings, and/or images will be gratefully received at the same address: jonvran@aol.com, and will be put up on the Occultation Section's web pages.

Peter Grego intends to do a web cast (www.lunarobservers.com) of the occultation from his location near Birmingham, so if you have cloudy skies where you are, there is another chance to see the event courtesy of the Lunar Section.