Lightcurve data for Europa has been very hard to interpret, so much so for a long time its period of rotation was in dispute (5 and a half, or 11 hours?) despite many observations. It has now been determined that Europa is a prograde rotator, but the exact direction in which its pole points remains unclear. The most detailed analysis indicates that it points either towards about ecliptic coordinates (β, λ) = (70°, 55°) or (40°, 255°) with a 10° uncertainty . This gives an axial tilt of about 14° or 54°, respectively.