Located in the Triangulum galaxy, Lehra is a cold, icy planet situated in a quadruple star system of mostly low-mass stars.
Composition & Atmosphere
Lehra is composed of 70% water ice and 30% silicate rock. The planet has four layers: an ice sheet, a subglacial ocean of water - home to thousands of lifeforms, the mantle and the core. The core is made of molten iron which powers the magnetic field. However, most lifeforms stay within the water ocean.
The atmosphere is mostly methane but with a small amount of nitrogen and even trace amounts of gases like carbon dioxide. At perihelion, Lehra's atmosphere is at its strongest pressure while at aphelion it's atmosphere partially collapses on to the surface with its weakest pressure.
Lehra is orbited by eight moons, three large moons and five captured asteroids in elliptical and inclined orbits. These asteroids are believed to be ancient comets that have lost up to 97% of their ice during the last eleven billion years. Only 3% of their ice, from the star system's formation, still exist on their surface.
The three largest moons have a small tidal effect on Lehra. The surface is raised by two feet (60cm) on a regular basis.
Lehra's surface is dotted with impact craters and, unsurprisingly, methane ice. Every impact crater dates back to at least 10 billion years ago, back to a period when the planet experienced a comet bombardment. Giant trenches also appear on the icy surface. Many scientists, about a decade ago, concluded that a subglacial ocean of water existed below the icy crust. Drilling units soon discovered microbes and entire ecosystems of plant life and animals.
Life exists within the subglacial ocean about 30 km from the surface. Due to the ice sheet, life in the ocean has no knowledge of outer space.