Brainstorming session for helium misestimation problems

[zhafen]

FH lessons issue 213.

[zhafen]

@zhafen, @CTarr schedule for a week from today

[zhafen]

Two weeks from today is when we actually need to schedule it, @zhafen , @CTarr .

[zhafen]

Correction: two weeks from today (observatory visit was pushed back).