Editing Foundation and Earth (section)

===Part V: Melpomenia===
The crew now visit [[List of minor Foundation universe planets#Melpomenia|Melpomenia]], the third and final Spacer coordinate they have, where the atmosphere has become reduced to a few thousandths of normal atmospheric pressure. Wearing space suits, they enter a library, and find a plaque listing the names and coordinates of all fifty Spacer worlds.  On the way back to the ship, they notice a moss has begun to grow around the seals of their space suits, and just in time, surmise that the moss is feeding on minuscule leakages of carbon dioxide. Thus, they are able to eradicate the moss with a blaster and heavy UV-illumination so that no spores are unintentionally carried off the planet. They then plot the Spacer worlds, which form a rough sphere, on the ship's map and conclude that the location of Earth must be near to the center of the sphere. This area turns out to have a binary star system.