Polaris (star)
Surprisingly, considering its relative nearness, its distance is not yet known for certain. Many recent papers calculate the distance to Polaris at about 434 light-years (133 parsecs). However, some suggest it may be as much as 30% closer. If correct, this would be especially notable because Polaris is the closest Cepheid variable to Earth. Its physical parameters are critical to the whole astronomical distance scale.