I have noticed that TiPS may be very near 27:2 resonance - its groundtrack nearly repeats every 27 revs, or about every 2 days. Based on my search elset, the resonance is 27.0068:2; based on Rainer's, it is 26.9963:2. On page 196 of a A Tapestry of Orbits, Desmond King-Hele states that the first satellite analysed at 27:2 was the Aureole 2 rocket, but severe drag limited the value of the results. Perhaps the tether will in some way limit the usefulness of this object for geoid studies. bye for now