SOLVED. Children kidnapped and sent into space [s]

[Ayla]

So It's about some little kids, I think the main character might be a little girl and it's a childrens/ ya book. It starts out with these kids whos dad is like this survival nut and always go camping and stuff and the girl almost dies from dehydration. Then they get kidnapped and sent into space where they have to perform these acrobatics for aliens and then it turns out the aliens are actually old people and it is underground not in space and them performing the acrobatics is keeping the old people young especially when one of them dies. The main character finds out and she becomes like a pet or something. I also remember for some reason that the author had a really long last name. I would love it if someone could help!!

[Kristina]

Ha, I think it is Galax-Arena by Gillian Rubinstein.

"Kidnapped from an Australian train station, Joella, Peter, and Liane are taken on a rocket to the Galax-Arena, where children stolen from Earth perform death-defying stunts for the amusement of the inhabitants of the planet Vexak"
". . .She becomes a pet to a Vexan who reveals to Joella that she is actually a frail old woman under grotesque alien makeup--and that they are still on Earth. . ."

[Ayla]

Yeah that is it I recognized the author imeadiately once I saw the name. Thanks for the help!

[Rainbowheart]

Galax-Arena for the link.