Vault of Tomorrow
The Vault of Tomorrow, entered through the Chamber of the Ages, was a Horta facility on Janus VI, near level 23 of the Federation Janus VI colony. It was a hatchery and nursery where about a million Horta silicon nodule eggs were stored and watched by the mother Horta. 

In 2267, miners of the colony inadvertently destroyed thousands of eggs when opening up level 23, causing their mother to go on a murderous rampage throughout the colony. ()

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Structures