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.
By the 2010 census, the number had grown to 32,013. It is part of the El Paso Metropolitan Statistical Area. The city is El Paso County's second-largest municipality, after El Paso. It has a council manager type of government with five city council members. Socorro is the 93rd largest community in the state of Texas.