Fundamentally, momentum conservation is linked to invariance under space translations. See Noether's theorem. If you want to find a system that does not conserve momentum you should look for situations where space is not uniform, e.g. balls rolling on the surface of a bowl, a planetary system (when the dynamics of the sun is neglected), etc.
Socorro is a city in Socorro County in the U.S. state of New Mexico. It is in the Rio Grande Valley at an elevation of 4,579 feet (1,396 m). In 2012 the population was 8,906.
Estancia, New Mexico. Estancia is a town in Torrance County, New Mexico, in the United States. As of the 2000 census, the town population was 1,584. It is the county seat of Torrance County. Estancia is part of the Albuquerque Metropolitan Statistical Area.