Here it is in a nutshell:
To begin with, Venus gets very close to the Pleiades once every eight years – and this is a sort of a warm-up to the Big Event – the transit of Venus across the face of the Sun on June 5. But a number of things excited me about this event, including:
- The mythology angle – the Seven Sisters meet the Goddess of Love!
- The distance angle – Venus is so much brighter, but think of how much closer it is – Venus is about four light minutes away, the Pleiades 400 light years. In 400 light years there are 210,240,000 light minutes – so that puts this beautiful star cluster roughly 52 million time farther from us than Venus.
- The 3D angle – seeing these two together – and knowing the above – really gives you a sense of three dimensions on a huge scale.
- The luck of the clouds angle – or aren’t “sucker holes” great!
- Oh yeah – and then there the whole motion thing – how the rotation of the Earth changes the position of the Pleiades – and Venus – a little each night – and how the revolution of the Earth – and, more important, that of Venus, also change quickly what we see. Venus going by the Pleiades gave us a good sense of the combined impact of these motions.
With any astronomical event like this your chances of seeing it are severely handicapped by the weather. I was hoping to see one night out of three. I saw it all three nighst – with a lot of luck!
The first night I took this picture after eight people had joined me at Driftway to observe Venus. I had asked them to come at 8 pm – the time the clouds were scheduled to depart according to the Driftway Clear Sky Clock. And darned if the Clock wasn’t right. It took them a full hour to disperse, but as soon as people arrived the clouds started to leave giving us peeks at Venus through what amateur astronomers like to call “sucker holes.” Actually, I find observing on an evening such as this through such holes kind of fun – and a good reminder that we live in a sea of air.
The second picture is all due to Eliza’s noisy alert. It had been clear all day – the night before it had been cloudy all day – and right at dusk it clouded over completely. I gave up. Figured I’d get to bed early and maybe in the morning it would be clear again as forecast. I was heading to bed at 9 pm when Eliza started barking wildly. We didn’t have a clue why, but I opened the front door, looked out, and there was Venus in a sucker hole! Wow! So I lucked out a second time. Three’s a charm 😉
And on April 4 – the third night – I was lucky once more. Clear all day – I set up scopes with high plans for the night – took a nap, and got up at 8:30. Mostly cloudy – as forecast, actually, but it wasn’t supposed to last. Still, this looked like the real thing. I did get a glimpse at Venus, though, and rushed into the house through the back door, grabbed my camera, went out the front door and started snapping as clouds climbed up towards Venus.
In the house 15 minutes later, I downloaded the pictures to the computer and saw I was out of luck. I caught Venus, but the Pleiades were already being obscured by the cloud. As I fiddled with the photos in IPhoto, Bren came in. “Venus is shining brightly in the west,” she said. Yep – but when I got out there the Pleiades had there own little cloud. I waited. The cloud went away and I got the last picture.
Is there a lesson here? Yes, certain weather patterns do give you these opportunities. I’ve seen them before, but I don’t know how to predict them. So the lesson is simple – keep looking up!