Space themed birthday party for 8y/o

Hi,

I have an 8 year old who has absolutely immersed himself in everything cosmic. It's all he wants to discuss, watch and read. With his birthday on the horizon he made it pretty clear what sort of theme he would like for this small party we are hosting at home.

I think I've got the decor sorted with backdrops, hanging planets, outfits, etc but I am at a loss as to what sort of space/physics activities I could provide indoors for about 2 hours to around 10 children.

Any suggestions or ideas would be fantastic

Thank you