Friday, February 19, 2010

Seaside Sunsets and a Conjunction!

More on our trip to San Diego last weekend... On Sunday, Sweetie's Day (14 February), we walked a LOT, and by the time we returned "home" to Pacific Beach, I got horizontal to help reduce the swelling in my knee while Melinda and Carolyn went walking down the beach and searched for adult beverages. I noticed with the exceedingly clear skies there might be a very nice sunset and indeed there was! The only telephoto I had was a 200mm zoom with 1.4X telextender, and I shot from our room on the 3rd floor. By sunset time, the Girls were in the bar on the ground floor, but likely within a few dozen yards of me. Melinda had her 300mm zoom and shot a wedding party out on the beach, with the sunset behind, zoom setting unknown. But what is truly amazing is the stark difference in the sunset appearance from the 8 meters of vertical difference between us. Hers is a standard sunset with an oval sun, but from 2 floors higher, an inversion layer split the sun and two slivers set! Here are my photos - click to enlarge!

And here are a few of Melinda's with no evidence of the inversion layer.

What I think is happening is that from my elevated position, a layer of cool air over distant pacific waters (that wasn't visible from Melinda's position) produced an inferior mirage that produced a second sliver of the sun near the ocean horizon. I've seen similar effects from high elevations like Kitt Peak while looking through an inversion layer and evidently they are not too uncommon.

In my nearly daily scan of astronomical events going on, I found there was to be a conjunction that evening. In the last few weeks, Jupiter has been falling towards the evening twilight, and Venus is coming out of the solar glare, and they were to converge with crescent moon Sunday night. We hadn't packed binoculars, which would have been very useful. The other disadvantage we had was that we were literally at sea level, far below the clear desert air we usually enjoy in Tucson. But with the clear skies, we were optimistic.

But as the twilight darkened, We spotted no points of light or skinny crescents in the west. I thought I saw a flash just above where the sun had set, so I used my camera and telephoto to take a shot - sure enough there was Jupiter, and to it's right was the thinnest of lunar crescents, and Venus was even visible below Jupiter. I went on to see Jupiter only 4 or 5 times, but never saw it's companions visually. I went on to take a half dozen images to stack and bring them out more clearly, but was definitely a tough observation from San Diego. Shown is a crop of the stacked image - click to enlarge. The ocean is at bottom - perhaps I should have started earlier before Venus was so low. Fortunately, David Harvey in Tucson had better conditions and recorded them more clearly.

I think one more California post to come!

1 comment:

Anonymous said...

What cool pictures!! It's crazy how a couple stories changes a shot!

FYI... The guy above is saying something like: Share friends first, share happiness second.