Space Research Journal1819-3382xxxx-xxxxAcademic Journals Inc.10.3923/srj.2012.10.14El-HameedAfaf M. Abd 1201251The distance between two stations was supposed to be determined from two pairs of synchronous optical observations. In addition, the optical observations were studied and analyzed in combination with one laser measurement. The expressions for the error of this distance have been obtained" and "the minimum error conditions have been investigated.]]>Batrakove, Y.V.,1969Allan, D.W. and M.A. Weiss,1980Ekuma, E.C.,2007Eckl, M.C., R.A. Snay, T. Soler, M.W. Cline and G.L. Mader,2001Chu, H., Z. Xie, X. Xu, L. Zhou and Q. Liu,2011Gili, J.A., J. Corominas and J. Rius,2000Lambeck, K.,1968Liao, D.,1985Ibrahim, M., A.M. Abd El-Hameed and G.F. Attia,2011Kaloop, M.R. and H. Li,2009Hakli, P.,2004Martin, S. and C.H. Jahn,2000Yuan, X., C.X. Zhao and Z.M. Tang,2010Hanna, Y.S., M. Ibrahim and S.W. Samwel,2011Zhongolovitch, J.D.,1970