What are some important ways that eastern europe is different from western europe?

Western europe contains countries where the borders are larger, whereas eastern europe, with the exception of russia, has more smaller, divided countries, as well as the west having more wealth due to the USSR damaging the east. The east also has a larger Roma population, as well as being more ethnically slavic, and religion wise is more likely to be Orthodox Christian unlike the largely Catholic or Protestant west

The answer is the magnetosphere.