COSI launched today, which means that SPIDER is coming up next. Unlike the usual zero-pressure balloons that are open at the bottom, they use a special pressurized balloon with a heavy valve plate on top to regulate pressure and avoid popping. This requires a smaller tow balloon to lift up the main balloon for inflation. A little over a week ago, they had a very unfortunate scrubbed launch after their fancy million-dollar balloon was out of the box and the tow balloon fully inflated. Due to extremely dense fog, that part of the process was invisible this morning, but the fog cleared up in time for us to see the launch. The lingering fog resulted in some spectacular light displays.

Waiting on the launch pad

Jon sets up some timelapse cameras
He has made several excellent videos

The Boss and COSI

The top of the balloon, fed through the spool

Inspecting the bottom of the balloon

Tow balloon inflation

This "small" balloon is needed to lift the top of the main balloon for inflation
COSI's special super-pressure balloon has a heavy valve plate on top

Tow balloon release

Cut away, launch scrubbed
Due to a change in wind direction. Will try again another day

Another day
We head out as the dense fog clears, and inflation of the main balloon is well underway

The balloon
And the tractor that's parked in our view

Early morning SPIDER team
Those that made it out before the roads were closed for the launch

Inflation complete. Tubes tied off

Mt Erebus pokes out of the fog beside the balloon

Ivan and the Balloon

Awaiting launch

Any time now

Balloon release

Rising

Awesome balloon eclipse
And giant shadow throughout the fog

Balloon mostly risen

The Boss needs to drive around a lot

Release

Away she goes

Rainbow launch
!!!

Fare well COSI!

Weird light cone forms after launch

Mt Erebus steam stream
Showing the winds at 4km alittude
Thanks for this ! Watching the Jan.1 launch !
That balloon Eclipse shot is great!