Monument

Monument of the XN-409 System was a A barren, rocky planet at the edge of the system's habitable zone. The planet's atmosphere is almost entirely nitrogen, and temperatures rarely rise above 0 degrees Celsius. Water exists on the surface, but usually in the form of frost. There are no life forms on Monument, but there are signs of past habitation; a number of rectangular obelisks have been found scattered across the surface, giving the planet its name. Nobody knows who built the obelisks or why.