Today’s Astronomy Picture of the Day features a view of Mauna Kea’s shadow on the sky, just at the tail end of last week’s lunar eclipse:
I couldn’t help but be reminded of our visit to the summit in April 2005, just at sunset, when I took this similar (but decidedly less cool) photo:
Atmospheric Optics explains why most mountains’ shadows look triangular when viewed from their summits.
Losing a tree to last weekend’s Santa Ana winds means there’s no more shade in the afternoon. Not an issue most of this past week, but Sunday was both sunny and hot, and with the window closed and the blinds open, all that heat went straight into the living room.
On the other hand, it does have its compensations:
Friday, September 28:
Adding to the mish-mash of photo sources on here, this is a still frame from a video clip taken out the window of the car. It wasn’t supposed to be a video clip, but my camera has a sliding switch for selecting photo/video/review, and it has a tendency to shift while in a pocket or bag. *grumble*
I stepped out of the office last Thursday (September 27—it was a good week for interesting late-afternoon skies) and saw this view to the west.
The clouds glowing as if from within, and the curved bands as if the whole set had been dragged across the sky, reminded me a bit of pictures of reflection nebulae.
Friday was the first rain we’d seen in over a month. By evening, the trailing edge of the storm was starting to cross central Orange County, and I actually drove back into the cloud cover to pick Katie up from work. We ended up stopping for dinner, and got back on the road around sunset.
At sunset, there were clouds above us, rain in the east, and clear skies to the west, showing a bright orange sun. We looked to the east, and saw a huge rainbow. It was extremely high—it looked like it ought to be an entire circle, even though I knew it couldn’t be more than a semicircle. That doesn’t come through in the one photo that came out, since it’s a matter of perception: neither of us had ever seen a rainbow centered at the horizon before. It was also faint (I had to increase the contrast on this photo), and very red.
Google Images pulls up some nice pictures when you search for rainbow sunset. I particularly like this one at Flickr, which also shows spoke-like rays. Atmospheric Optics’ rainbow section is also worth a look, especially for some of the odd kinds of rainbows that aren’t often seen.
