- What are the pole angles X and Y?
- What is Universal Time (UT1)?
- How does the stellar angle theta (or Earth Rotation Angle) differ from GST?
- How much is the accuracy of precession/nutation improved by MHB2000 and corrections to the precession constant and obliquity rate over the current IAU models?
- What is the limitation on the accuracy of the new models?
- How can the existing nutation correction time series be converted to the new X, Y angles and vice versa?
