The invention relates to a deep space explorer acquisition phase 
celestial navigation method based on target object 
ephemeris correction. According to the method, firstly, a Martian explorer 
state model, a startlight angle navigation sub 
system measuring model and an X-
ray pulsar navigation sub 
system measuring model are built; then, the startlight angle and the X-
ray pulsar quantity measurements are respectively obtained; filtering 
estimation is performed to obtain the position and the speed of a 
detector in a heliocentric 
inertia coordinate 
system and a target object center 
inertia coordinate system; on the basis, a 
state model and a measuring model of target object 
ephemeris error are built; the quantity measurement about the target object 
ephemeris error is obtained through 
estimation state vectors of the startlight angle navigation sub system and the X-
ray pulsar navigation sub system; a Kalman filtering method is used for estimating the target object ephemeris error; the target object ephemeris error is fed back into a 
navigation system model; the position of a target object in the 
navigation model is corrected. The deep space explorer acquisition phase 
celestial navigation method belongs to the technical field of 
aerospace navigation, can be used for estimating the object ephemeris error and correcting the model error of the 
navigation system on line, and is applicable to the explorer acquisition phase.