Tom Tee posted:Maybe the helium car could make it up to space??
What is the gross weight difference between an empty helium car and a full helium car?
Believe it or not, there was a debate about it years ago in the NMRA Bulletin. I don't recall the details, but yes, a helium transport car weighs more loaded than empty. When helium is compressed, it loses its buoyancy.
After all, helium (or hydrogen) isn't upsidaisium.
Rusty