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Observations for 28 July 2012

Turns out I was wrong about the next Grand eruption. Thanks to a sub-six hour interval, Grand was able to erupt on what was probably the last Turban before the moon set. The eruption itself was 3 seconds short of 13 minutes, but was perhaps still the best possible one burst Grand eruption.

Dawn Fog #1 Dawn Fog #2
Dawn fog in the Upper Basin
Even with the short intervals, Grand is finding it hard to erupt twice at night. The next eruption window began well before sunrise, and this time featured a 36 minute Turban interval on which Grand started. It not only managed to have two bursts totaling about eleven minutes, but also Vent & Turban continued following the eruption.

With nothing much to do, I decided to check out the time of first overflow. It's been a long time since I paid much attention to it, since in never really changed, but with these short intervals, wondered if that might have some bearing. What I saw was inconclusive.

Where in the past I've assumed a 4-1/2 hour refill, today it took 3h53m. It took only two Turban eruptions for the crater to go from empty. Then it got a bit weird. West Triplet started, so I decided I'd wait until WT ended, and get a possible Rift start. Turban erupted early during that time, so not surprised that Triplet ended without a Rift. But out at Grand, while I didn't see a Turban eruption, I did see a full pool pouring out water and maybe even some waves. At about 4-1/4 hours after the previous eruption. Finally, the pool subsided and Turban erupted at 37m20s, which was even longer that the earlier delay overflow that turned into the eruption.

Only missed a Turban eruption, and was curious to see what would happen next. Grand ended up with a moderately long interval of just less than seven hours, and erupted on the seventh Turban following the heavy overflow. Interesting co-incidence there. None of the preceding Turban eruptions showed anything remotely like they were leading into an eruption, either.

So that meant were were almost certainly going to get another four-Grand day, with three of them in daylight. Or maybe not, as Grand had a delay which pushed the eruption back five Turban eruptions and gave us a nice moonlight eruption instead.

The entertainment preceding the eruption was a paper plate which had blown into the runoff channel below Turban the day before during the storm. This time a strong wind suddenly came up out of nowhere and move the plate closer to Grand. A second gust pushed it right into Grand's pool, where if floated around. Unfortunately, this all occurred after sunset, so after a bit the plate was no longer visible. It did not appear floating down the runoff to New Orleans during the eruption either, so it must out there somewhere. Will have to look for it tomorrow.