I know, it's after the fact. I meant to post here beforehand, but I had stuff going on.

Solstice was just here. Interestingly, there is a park in the Clear Lake, Texas, (near Houston and JSC) area that has been built for observing the sun's motions. It has some granite stones set up to form portals to mark the rising and setting points for solstices. It is not like Stonehenge, only 4 a pair of standing stones, no crosspieces. Still, it is interesting with a spartan leanness.

The monument has a large concrete area, with a central court that has a labyrinth marked in the pavement (no actual barriers, just markings). The court is ringed by 4 pair of small square stones at the 4 corners for NE, NW, SE, and SW. There are pavement divider marks (but no identifying markers) that align for the cardinal directions.

Some friends and I decided to check out the park on June 21. We got there, and there were about a couple dozen other people there to enjoy the monument. Unfortunately, we discovered that there was some sort of error in construction, and the sun didn't make it through the portal.

This park was supposed to have been constructed to match specifically for Houston. For some reason, though, it was off just a hair. The sun ended up behind one of the stones, not visible through the portal, when we stood in the proper place. Disappointing.

We have no word on if it worked for sunrise. There are stones in place for it, but no one was up to check it out. I almost did, but didn't make it.

Anyway, we had fun.

I did have one question - actually a verification. The monument has 4 pairs of stones, two on the North of the E/W line and two on the South - symmetrical. The summer solstice goes down in the more Northerly pair of stones. The juxtaposed set of stones would be the Southern pair on the East. But I think the sunrise should actually come up between the Northerly pair of stones, same as sunset. My rationale is that this is determined by the cant of the poles - in summer we're pointed more toward the sun so the sun goes higher in the sky. Daylight is longer, and the horizon points are farther North because of the tilt. The Winter solstice would have sunrise and sunset through the more southern pairs of stones. Am I correct?

Anyone in the Houston area wanting to check it out, it is located off Clear Lake City Blvd, just East of Hwy 3.

Correct, if I understood your description.

As to why the sunset alignment wasn't accurate, it could have been an error in construction (as you suggest). But there's another possibility.

A solstice doesn't last all day. There's only one moment when the Earth is actually at the solstice, and that was not right at sunset. The exact time of the solstice was 2:10PM CDT. Perhaps the spacing of the stones is so tight that a six-hour error is enough to put the Sun behind a stone rather than between the pair. If so, this means that it would be a rare occurrence for the device to work properly.

Another possibility is that you weren't exactly at the correct observation spot. That could be fairly critical, depending on the distance to the stones and separation between them.

You might want to visit the site again in the next few days, to see how far the sunset position has moved.

Sounds kinda like a piece of artwork that my college bought. It was a strange sculpture thats shadow at 10:00 am on the Spring Equinox was supposed to lay right on a pattern on the ground and a nearby wall.

The first spring, we all gathered to watch it. The shadow missed by a country mile. Turns out the designer didn't account for the fact that the college was at 40 degrees north, and he was at 32. :-?

Interesting comments. Someone who was there said he had been there the previous year and it didn't work then, either.

One possible suggestion was they didn't take into account the difference between true north and magnetic north, but I don't think that's the explanation. They also appeared to take the latitude into account.

The stone circle is about 130 ft diameter (from my fuzzy memory). The stones are 8 ft tall granite slabs. The gap between the stones is ~ 4 ft. There is a marked spot in the center of the plaza, but the viewing position is actually anywhere along the line from the correct portal to the portal 180 degrees across.

A close scrutiny of the pavement shows a divider line between concrete slabs that runs along the cardinal directions, plus divider lines in various other places. Of particular note is the divider lines that run along the direction between the two pairs of slabs for this viewing. The line does not quite go straight, but makes a minor bend in the middle from the easterly side to the westerly side. Someone suggested that the precision required was a little more than the construction crew put in for what is mostly just a park decoration. *shrug*

Is it Sylvan Rodriguez Park? The artist Dixis Friend Gay seems to have been the one to design it. She says she had help from the BA's friend, Sten Odenwald.

PS: Oops, just noticed:
The link I gave above says that the correct viewimg position is the center of the of the plaza: "When one stands in the center of the plaza, split stones mark the point on the horizon that the sun will appear to rise at the northern most point (about June 21) and the southern most point (about December 21) during the year. "

The stones are so far apart, I can't imagine that the different time of the solstice (the six hours Donnie B. suggested) could make that much of a difference.

Yes, that is the correct park. My buddy was trying to make a picture like the one shown. Notice the large stones on the near side, the person in the middle, and the small stones on the far side. The sun is overexposed so the glow blots out most of the far stones, but silhouettes the person. Notice that the camera is not at the center of the plaza (the "correct" viewing location), but lies along the line through the middle from the correct stones, which also aligns with the stones on the far side.

The reason for that position is because it isn't difficult to find an angle to view the sun through the stones, but viewing through two sets of stones only happens on the correct day. That works better for a picture, which can't show the correct standing position in the center of the plaza very well.

That picture shows it works for Winter Solstice, so it's only Summer that's not quite right.

The rising of the sun on the summer solstice does move a little, as Donnie B. suggests, because the actual solstice is a moment that can be early in the day or very late in the day--the solstice actually occurred on June 20, in the year 2000, in Houston.

However, the sun's rising position doesn't change that much from day to day at the solstice (it's "stopped and turning around"), but it looks like you are making an assumption that the view from the SW gap to the NE gap should line up with the rising sun on the summer solstice, and the view from NE to SW should line up with the setting sun on the winter solstice. I ran a couple checks, and that's not quite true--the angle seems off by a degree. Also, the Sun will move a degree in azimuth in just ten minutes, as it's rising.

The figures that you give (4 foot gap, 130 foot diameter) gives an angular gap of 4/65 radians, or about 3.5 degrees. So, maybe the artist had to make some astronomical concessions to make the whole thing symmetrical--if it is symmetrical as you say--but made the gap large enough to allow for winter/summer differences and the day-to-day differences that Donnie B. mentions.

However, when you stand at the edge of the circle, and sight across the entire field, the gap appears to be half that--4/130 radians, or only 1.75 degrees. Perhaps it works when you stand at the center, as it should, but you've narrowed the gap too much when you try to sight from one pair across to the other, for your photograph. If you stand back so that you can get the near pair in the photo, the situtation is even worse--you're even farther from the far gap. You could gain some leeway by moving left or right, but then it wouldn't be centered.

PS: I found a couple webpages from a Houston astro club that went out at the winter solstice and they found the artist in costume, following the maze. Maybe she was there at the summer solstice?