Planet Dossier: BethselaminCopy Anchor Link

"For instance, on the planet Bethselamin, which is a fabulously beautiful planet and gets visited by ten billion tourists a year, they are so worried about the cumulative erosion that any net imbalance between the amount you eat and the amount you excrete whilst on the planet is surgically removed from your bodyweight when you leave: so every time you go to the lavatory there it is vitally important to get a receipt."

— The Hitchhiker's Guide to the Galaxy, Chapter 8

Bethselamin is a fabulously beautiful resort planet that attracts ten billion tourists a year. Compiled in The Hitchhiker's Guide to the Galaxy by roaming travellers and researchers as a prime example of essential interstellar travel advice, Bethselamin is equally famous for its breathtaking scenery and its draconian anti-erosion customs enforcement.

The Cumulative Erosion Crisis & Surgical Departure AuditsCopy Anchor Link

With ten billion visitors arriving and departing annually, planetary authorities on Bethselamin are deeply worried about the cumulative erosion of the planet's mass if tourists leave weighing even slightly more than when they arrived:

1. Strict Mass-Balance Accounting: Upon departure, customs officials calculate the exact net imbalance between the amount of food and drink a visitor has consumed and the amount they have excreted whilst on the planet.
2. Surgical Bodyweight Removal: Any net positive imbalance between intake and excretion is surgically removed from the visitor's bodyweight when they leave the planet.
3. The Lavatory Receipt Mandate: Because every gram of excreted matter must be rigorously documented to avoid the departure scalpel, the Guide emphasizes that every time a traveller goes to the lavatory on Bethselamin, it is vitally important to get a receipt.