Yes, it is possible to access an instance variable from a static method without using a parameter but only if you can access it via something that is declared static. Example:
public class AnotherClass
{
public int InstanceVariable = 42;
}
public class Program
{
static AnotherClass x = new AnotherClass(); // This is static.
static void Main(string[] args)
{
Console.WriteLine(x.InstanceVariable);
}
}