Venus and Saturn

Venus is approaching Saturn and this evening the planets were separated by about one degree. Unfortunately I did not have my scope available since I am at my summer house. However, I got a good look through binoculars. The planets are close enough to get both in the same field of view. The full moon also put on a show with the illusion of a larger than normal moon hanging low in the sky as it rose over a shimmering silver reflection in the sea.

Occultation of Venus

Today I had a chance to do some daylight astronomy. Venus was scheduled to be occulted by the Moon at 17:01 local time (15:01) UTC. I started observing some two hours before. The proximity of the Moon to Venus was a good opportunity to observe the planet in daylight. The planet was easily visible to the naked eye as a small bright point to the South East of the 12% crescent Moon. The position was very high in the sky, at 17:00 it was at an altitude of almost 70.5 deg.

Slowly the Moon moved Eastwards, ever closer to the planet. Exactly on time, as I observed through binoculars out of my office window, Venus suddenly grew fainter and disappeared. By the time it was to reappear at 18:01, I was home and quickly set up the telescope to better observe and photograph the event. The planet reappeared in the area of the crater Humboldt. I was surprised to see how much brighter the planet is compared to the Moon's surface. The sight of the 44% planet next to the much larger 12% moon was spectacular.

One of the photos I took just after the reappearance is shown above. A larger version can be seen here .

Jupiter and Sagittarius

The main object of my session was to observe Jupiter, now at its maximum altitude to the South in the evening sky. The view of the giant planet was magnificent. The cloud bands were visible in some detail. The North Equatorial Bands were more pronounced and the South Polar Region was darker than the North. The Great Red Spot had just passed the central meridian and was moving to the West. The moons were all to the West, Io and Ganymede close to the planet, Europa further out and Callisto close to its greatest elongation.

I also viewed the nearby M4, which is close to the bright orange-red star Antares. I could resolve it with a magnification of 120 but unfortunately it is swamped by light pollution close to my South horizon.

With Sagittarius now well above the horizon, I took the opportunity of viewing some of its DSOs. The M8 Lagoon Nebula and the open cluster NGC6530 looked fantastic through the UHC filter with the dark lane in the nebulosity clearly visible.

Just above the Lagoon is the Trifid, fainter but visible through the UHC filter. I followed a trail through the Sagittarius star cloud M24 up to M17 the Omega (or Swan) Nebula. This is another magnificent nebula with some structure visible through the filter. I went up to M16. The cluster was visible but I found the Eagle Nebula, of Pillars of Creation fame, rather faint.

Other objects I viewed were the M27 Dumbbell Nebula, the M57 Ring Nebula and the M11 Wild Duck Cluster.

Omega Centauri

With the days getting longer and Omega Centauri (NGC 5139) culminating earlier, this is about the last chance to view the great globular cluster. I had never seen it but I had resolved to observe it this year. Having been foiled by cloud and light pollution I took the opportunity of today's cloudless albeit windy evening to go to the cliffs on the South of the island armed with a pair of binoculars. I arrived before 20:30 with culmination estimated to be at around 21:15. It was not yet dark with only Venus in the West and Jupiter in the East visible. As time passed the stars appeared; Arcturus overhead, Antares just to the West of Jupiter and Spica. The latter was important to me since Omega Centauri is to the South of it. By 21:15 the stars of Centaurus started to become visible low to the South. At first I could not see the cluster although I was sure of its position but at around 21:30 I observed it. Starhopping to it is easy. Menkent (theta Centauri) is a bright orange star almost directly south of Spica. Further South is phi Centauri which forms a distinctive triangle with mu and nu. Further South still is zeta Centauri, a +2.55 star. Omega Centauri is to the West of this star, the distance between mu and zeta being about the same as between zeta and omega. Next year I must take the telescope to view it better.

I also observed the other great globular M13 as a comparison, smaller but brighter because of its much greater altitude in the sky.