June 30, 2015

Blackheath Observing – Conjunction of Venus and Jupiter

Jupiter and Venus Conjunction

Report by Rupert Smith

Following a successful FAS Members Solar Observing event at the ROG, we setup on Blackheath in preparation for the conjunction of Venus and Jupiter. The event started before the scheduled 9pm while the skies were still quite bright (and clear – more on that later!). Right from the start we had a large attendance with perhaps around 70 people plus over the course of the night. Many visitors had also bought telescopes, there being perhaps 20 available to view.

The first solar system object to appear was the 98% illuminated Moon, looking extremely large as it rose above the horizon in the still bright blue sky. Despite being almost fully illuminated, it did not disappoint and provided some early wow’s from the visitors with shadows cast of its more mountainous regions.

As the sky began to dim a little as we entered twilight, Venus began to appear above some annoyingly thickening cloud. Through a 100° eyepiece at 92x the crescent of Venus was clearly visible and joined to one side by the familiar shape of Jupiter, its cloud belts easily seen despite the still quite light twilight sky. Within the space of perhaps 15 minutes, Jupiter’s four Galilean moons also came into view to complete a picture that will not come close to being repeated for another 8 years.

Telescope set up on Blackheath

Soon, as if to warn us what was to come, heavier clouds began to obscure our view despite the Met Office’s assurances of a clear night. Typically to the East, where there was nothing of interest, it remained clear!

Despite the cloud, a new point of light had appeared to the south indicating that we would now be treated to the delights of Saturn. It did not disappoint. Despite being low in the sky, the favourable tilt of its rings delighted the many Saturn ‘newbies’ who got their first sight of this distant planet. Despite the still relatively bright sky, the Cassini division was visible, as was some of its colouring.

Unfortunately the cloud that had concluded our views of the Venus, Jupiter conjunction now moved east to obscure Saturn also. After much wishful thinking and the odd glimpse, Saturn was gone and it was time to conclude what had been a highly successful night for attendance. The clouds had one last parting gift for us though, as spots of rain began to fall!

All in all a very successful pair of events. We look forward to revisiting the Planets when we venture out on to the heath once more on Saturday July 11th!