Preliminary orbital control strategy for LISA

The proposed Laser Interferometer Space Antenna (LISA) mission design presently employs three spacecraft in heliocentric orbits with low inclinations and eccentricities, and equal initial mean longitudes. The resulting configuration forms an equilateral triangle whose sides (the arms of the interferometer) remain nearly constant in length, approximately 5 × 10⁶ km over each revolution; however, some active control is required to assure more precise formation-flying. This paper presents the results of numerical studies to determine a thrust history that maximizes the time between firings while reducing the range-rates between spacecraft, thereby reducing problems with Doppler shift in the interferometry.