Real weather, simulated observations

We're nearing the end of the altiplanic winter here in the Atacama, which means (fingers crossed) we should get back to observing soon.  The other night we were very productive with observations, but last night was somewhat of a different story.  Snow at the array meant we were shut down for the night, limited to running the antennas in "simulation mode", which means we can test the software and the observing scripts, but the antennas only pretend to be observing (they're not supposed to actually move if there might be snow/ice on the surface).  So, the weather wreaked havoc on the observing plan, but it did bring some pretty dramatic (and admittedly incredible) scenes in the afternoon.  I tried to document it all.

(1) Sand storm -- In the time it took me to walk from my room to the control room, the sand storm blew by, probably about 10-20 km, which means it was moving about 60 km/hr (from my very rough estimates).  It fortunately didn't arrive all the way to the OSF (fortunately, because I hear the sand is impossible to dislodge from your ears, face, clothes, etc).  I wanted to capture the whole scene, because to the north was a thick cloud of sand, but to the south was still sunny and clear.  Above is the 360 panorama I patched together.  If you google something like "Atacama sand storm", you will see that this must be rather common after all, and produces plenty of intense scenes.

(2) Rain(bow) -- Every time it rains here, we head outside, just to feel the cool moisture on our skin.  Someone usually comments about how this should be the "driest place on earth".  Well, it did rain here, but it passed in less than 5 minutes.  Clouds in the direction of the antennas is not a good sign for the night, but at least the rain left behind a full rainbow.

(3) Cloudy (bad) sunset (good) -- Again, astronomers may regret to say that some cloud cover produces the most gorgeous sunsets.  Well, if we can't be observing, at least we can appreciate the beauty.  Here I was enjoying the sunset with one of the other astronomers on shift. 

(4) Snow vs. antenna -- An antenna makes the ~30 km journey from the OSF (3000 m elevation) to the AOS (5000 m elevation) very slowly and carefully, aboard the specially designed antenna transporter.  Any sign of weather, and the move is cancelled.  This afternoon, along with all of the other crazy weather that blew in, some snow arrived at the high site before the antenna, and the transporter was forced to turn around.  We (the astronomers and array operators) at least made lemonade from the lemon-y weather, and hung around to enjoy the show as the antenna was returned to its temporary home near the control building, where it will wait out the bad weather.  Check out more photos (uploaded on Picasa), and the video I took, but maybe it's better in fast-motion.  In case you're interested, the transporter has 28 wheels that can move independently, and can place the 100 ton antenna on its station with 1 mm of accuracy!!  The driver makes most of the journey in the cab, but for the final moves, the transporter is operated with a remote control (it seems sort of like a really exciting video game).   

... All of this exciting weather ultimately shut us down.  These were the most "real" things that happened, all within about 1 hour this evening, before we headed inside for the night of observing in "simulation" mode.  So, enjoy the photos and the dramatic stories now, and I hope that I won't have anything more to report of this nature in the future!!