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Observations for 2026 September 22


We decided that we needed to get some sleep, so were not out in the Cage overnight. Instead, we arrived just before 06:00, while it was still dark. It was another cool day that started out cold, damp and foggy, but once it cleared around 10:00, it was actually nice, although the sun was rarely visible

Overnight nothing much had happened since the relatively strong Giant Hot Period that had allowed us to head in the night before. During the next 3-1/2 hours, we saw some short Bijou pauses, and the occasional Mastiff surge, but no visible water in Mastiff, and all the pauses were relatively short.

So I left to catch a Grand, in part to get out of the cage for a while. Grand cooperated, and I only had to wait an hour for the One Burst Grand eruption. There was absolutely no wind, so it was hard to see the activity through the steam.

2026-Sep-22 : 10:49:50 G1Q

 10:49:50	B1	--- d=11m43s
 10:49:52	Turban	0m02s
 10:52:57	Vent	3m07s
 11:01:33	P1	11m43s
 11:02:13	V&T Quit	12m23s

				     	ΣD=11m43s
	* * * * *
 09:36:20			d=03m16s	
 09:53:56	Int: 17m36s	d=03m40s	
 10:13:19	Int: 19m23s	d=03m57s	
 10:32:25	Int: 19m06s	d=03m45s	
		      Grand: 17m25s

After that, it was back to the Cage, where nothing continued to happen for the next 2-1/2 hours. We would get occasional Mastiff surges, and sometimes Bijou would pause, but the pauses were short and only once did Mastiff show water.

The big excitement/entertainment was having a bison appear near the trees in front of Oblong, and having it slowly make its way north. It passed right by the Cage, trailing lots of insects and a strong odor.

Bison passing by Bijou Cage, 2026 Sep 22.

Finally, at 14:43, we saw Bijou suddenly pause with Mastiff having a large surge. At that point the activity progressed in the way we usually get for a Standard Bathtub, until about three minutes in Feather started pulsating. Within a minute Feather was erupting to about 10 cm, at which point it stopped for several seconds before restarting and then coming back strong.

By then, Mastiff was near overflow, but it still took about two minutes for Mastiff to reach and begin to overflow. At this point, it became apparent that we were going to either get a strong Hot Period or maybe even an eruption. Mastiff then started surging, and then it too dropped and was quiet for a while.

More and more of the small platform vents began to erupt by this point. Catfish restarted, along with Bijou. Within seconds of Mastiff's restart it was erupting to 3-4 meters, higher than Giant's Cone. At the same time Giant was vertically surging to the top of the cone.

Mastiff erupted over five meters high for over a minute, with Giant's surging becoming stronger and more sustained. I would guess Mastiff reached twelve to fifteen meters at some point, although it was hard to see through the steam. Mastiff was so impressive that no one noticed that Feather's Satellite had started erupting at about the same time, something I had to see from a video replay.

By then I had abandoned the Cage for the walkway to the south, in order to see the start of Giant's eruption instead of getting drenched. The start was as quick as always, and Giant quickly got up to full height, measured to over 200ft. The only part of the Cage which got wet, based on the wet boards, was around the post where I had mounted my camera.

Since it was a daytime eruption, it was crowded in the Cage. Before I abandoned it, I think it had filled with a Chinese tour, with too many people trying to get their selfies. Back on the walkway, things were a bit more civilized.

After about 45 minutes we started getting restarts. First it was Feather, then the Satellite, and finally Posthole was seen for the first time in years.

14:43:15	Mastiff surge, Bijou already off
14:44:30	SW Vents spit
14:44:57	SW Vents erupt
14:46:07	Feather push, Mastiff at ovfl
14:46:28	Feather ovfl
14:46:56	Feather
14:47:01	Feather pause
14:47:09	Feather restart
14:47:27	Catfish erupting
14:48:10	Mastiff below ovfl
14:48:34	Masfiff ovfl
14:48:46	Cave erupting
14:49:34	Mastiff front surging to 1m
14:50:05	Mastiff erupting
14:49:47	Bijou restart, Catfish quiet
14:50:12	B-C vent erupting
14:50:22	Rust erupting, Mastiff ovfl only
14:50:49	Mastiff front to 2m, then quiet
14:51:39	Catfish restart
14:52:30	Mastiff start
14:52:34	Feather Sat. erupting
14:52:37	Mastiff to 3-4m
14:52:50	Mastiff 5+m front vent
14:54:01	Giant vertical above cone
14:54:09	Giant start of eruption

15:39:27	Feather restart
14:43:10	Feather Sat restart
14:51:48	Posthole erupting

At some point, someone seems to have deliberately and slowly lowered my camera, so it no longer was centered on the platform. I did manage to correct it when I had to change batteries. I stopped recording at about the time the eruption ended.

All of signs moved this eruption. I especially enjoyed how the attempt to block the Giant sign into place failed miserably. It can be seen rolling in my Hot Period video. The Mastiff sign ended up under the Cage.

Locations for four Giant Platform signs.
Location of Mastiff Sign

I left as the eruption ended because of what appeared to be nasty weather headed our way, rains which never happened. I also decided to not bother with Grand's upcoming eruption, so of course it not only has a short (less than seven hour) interval, but has two bursts.