The surface and atmospheric conditions on Njord make life impossible planetside. Even on the frozen ammonia seas, the turbulent violent nature of the Njordan atmosphere in which one of the feared Methane Cyclones can develop and sweep across half the planet in 2 hours, effectively preventing even the existence of domed cities. The intense gravity on Njord also makes unprotected existence impossible. Consequently, there is no life on the planet of Njord. Only the mining crews from the orbiting moon of Heimdall ever set foot planetside and then only for brief, nerve-wracking workshifts. Thousands of miners die every year mining Tibanna gasses from the planetary surface. But because of the immense profits they might make, hundreds of miners continue to volunteer for the duty every day.
Njord would have been ignored if not for the abundance of Tibanna gas which is mined to keep the Imperial war machine of the Emperor's Hammer Strike Fleet operating efficiently. Tibanna gas is an extremely rare gas that is used primarily as a hyperdrive coolant and blaster/ion enhancer. When the gas is spin-sealed and frozen in carbonite, it is converted into a simple form that can be readily transported to where needed. The quality of the Tibanna gas on Bespin is legendary but has been tapped primarily by the New Republic after the Battle of Endor. However, the Emperor's Hammer is fortunate that the Tibanna gas is both abundant and also naturally spin-sealed by the chaotic and intense atmospheric pressures of Njord. Several corporate mining crews will sortie from Heimdall each day to perform the highly dangerous, but necessary and highly profitable collection operations.
Tyr is a small (2,000 km) geologically unstable moon of Njord. Its surface is intensely scarred with by craters from meteor impacts from the Frey Asteroid Belt. Its surface is also marked with many hydrogen volcanoes, perhaps the most fantastic and deadly sight in the System. When the temperature of trapped hydrogen beneath the frozen Ammonia and Helium seas becomes too high as it rises to the moon's surface, there is a massive fiery eruption as the hydrogen escapes and ignites under its own kinetic energy. The result looks like a ball of flame rising from the planetoid.
Several mining corporations have attempted to consolidate the hundreds of claims and stakes on the planet of Njord. But so far to no avail. There is too much money to be made. The mining operations are independently owned by various small corporations, families and even individuals. However, even this apparent organizational chaos is working remarkably well since the amount of military-grade Tibanna Ion and Blaster gases exported from Njord is at record levels.
Civilization on the barren, lifeless Heimdall is confined to one large, sprawling Spaceport/Mining City named Valhalla. This city is a marvel of modern engineering, a permanent city over 6 kms in diameter is completely and securely anchored into the underlying frozen methane seas. The city is completely self contained with impressive, state-of-the-art recirculation systems and self-contained hydroponics, technical, economic and living sections. Emergency repulsorlift generators have been placed throughout the support structure in case of increased geologic activity. The Tibanna gas collection, precipitation and refining plants of Valhalla are constantly running. Approximately 500,000 Human (Imperial) colonists, gas miners, technicians, guildsmen, administrators, etc. inhabit Valhalla.