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.
Farmington, New Mexico. Farmington is a city in San Juan County in the US state of New Mexico. As of the 2013 population estimate from the United States Census Bureau the city had a total population of 45,426 people. Farmington (and surrounding San Juan County) makes up one of the four Metropolitan Statistical Areas (MSA's) in New Mexico.