Ritual Unicorn Sacrifice

Yesterday was a double-occasion: Suren’s birthday, and the first time that we filled the cryostat with liquid nitrogen. To celebrate, and to appease the temperamental cryogenic gods, we performed the ritual sacrifice of a unicorn (pinata). The liquid nitrogen is used to pre-cool everything before we switch to the even colder liquid helium.

In the week leading up to this point, we had to test for leaks in our vacuum vessel (and had no leaks!), pump it out to thermally isolate the different temperature stages, and test all of our cryogenic gear.

Outside of cryostat progress, we also completed the second run of the Bemco thermal/vacuum test chamber, built the gondola frame that will carry everything in flight, and started testing some of our calibration equipment.

Big vacuum manifold

For alternately pumping out the vacuum vessel, and purging with dry nitrogen

Testing windows

On top of the cryostat. The windows are quite thin, so we check frequently to see how they're holding up

Turbo pump

The collection of vacuum equipment in front of Lloro grows

Leak testing

We reach low enough pressures to start searching for any leaks. In the leak checker manifold first

Bemco debugging

You know things are going "well" when the oscilloscope comes out

Gyro box

Inside the box of gyroscopes, which caused a lot of problems (though the main problem was us being tired and confused)

Sho sorts sun shield spars

The gondola frame

Was fully assembled over in the east highbay

Jared assembles and tests the TRPNS

Our main polarization calibration device

Bunny suit gensturing

Who's inside?

The cat

Discovered one day that climbing up on the cars can stop people form leaving

Elle and Suren take a break

More TRPNS assembley

("Thermal Rotating Polarized Near-field Source")

And its finished state

Cryo/vacuum gear to test

Before we can start filling with liquid nitrogen

One of the two leak checkers stopped cooperating

So Simon and Suren peek inside

Extra thick vacuum window

To help protect the new flight window we installed this run

Big Pumpin'

We reach low enough pressure to install our more powerful turbo pump

Final state for Bemco run 2

For thermal/vacuum testing of all the gondola motors and pointing sensors

Oops!

The "empty" box that I'd stacked star tracker components on top of had bubble wrap inside. Which inflated and toppled things in vacuum.

Installing the new flight hard drives

Now that they've survived two runs of thermal/vac testing

Flight computer modifications

Empty Bemco

As we finish cleaning up the space

Reaction wheel assembly

Can proceed now that the reaction wheel motor, at the center of the gondola frame, has been freed from the Bemco

Early shift

Sunrise and the moon, as a few of us arrive early to prepare the first liquid nitrogen fill

The launch pad

And surrounding, recently mowed fields

First liquid nitrogen fill!

As Suren, Corwin, and Elle start cooling Lloro down

Reaction wheel motor installation

Takes a bit of wrestling to align

Installing the spokes and weights

Leveling the reaction wheel

With the digital protractor

The unicorn

Arrived mysteriously one night last week. Does it know what's coming?

Un-safety glasses

Elle modified some glasses to be a festive blindfold

SImon pulls the strings

Suren winds up

Armed with our biggest wrench

Looking cool in his glasses

The final blow

And sweet, sweet candy guts

Aftermath