It's 2 days after the winter solstice & things are turning ugly... 2 huge cold fronts on the way - starting with ferocious winds exceeding 120km/h!
There's only 1 thing to do: go outside & play, of course :) Ockert, getting blasted in the process, took this movie of Eben & Amanda "wind-surfing" behind SALT!
The 3 lunatics then set about circumnavigating the dome - Eben clockwise, Ockert & Amanda anti-clockwise. Their trajectories closely resembled those of protons being flung out of a particle accelerator & all earned style points for their creative decelerations - ouch ;)
Meanwhile, an alarming scene unfolded in the lounge: a mechanical engineer dabbling in electronics... This photo carefully conceals the individual's identity.
Having attached our fancy new adjustable LED, we got a wavefront measurement of M5 (0.1 waves RMS). With that, the M5 test's fully commissioned :)
In this test, a pinhole placed at M5's one focus is imaged at the mirror's other focus. What's really neat is to remove the wavefront camera & look down through the hole in the super-structure platform & see the pinhole "floating" in mid air! We used a small flat mirror to make it a little easier to photograph the image of the pinhole.
The bull's eye on the CGH can only be seen with a microscope so it won't allow us to centre the CGH when we do the system test. But it can be used to set up crosshairs which will be visible to the interferometer, so Amanda kindly donated two 50 micron strands to the cause & Francois's making good progress with that...