Abstract: In this paper researched the ground spectrum characteristics and star magnitude of spacial non-self-illumination object which is probed by Adaptive Optics System (AOS). The non-self-illumination object reflects sunlight into wavefront sensor system of AOS through atomsphere. The photon speed entering AOS's subaperture is also evaluated. In the contrast, compared the differences between sunlight-reflecting object and laser-illuminated object.