%0 Journal Article %T Modified Newton¡¯s Gravitational Theory to Explain Mercury Precession and Light Deflection %A Keli Kou %J Open Access Library Journal %V 8 %N 8 %P 1-9 %@ 2333-9721 %D 2021 %I Open Access Library %R 10.4236/oalib.1107794 %X By introducing relative speed of two objects into Newton¡¯s gravitational theory, Newton¡¯s gravitational formula can be modified as: F = GMm/r2(1 V2/C2). V is the relative speed between the two objects and C is the light speed. In order to test this formula, the paper uses it to calculate the Perihelion Precession of Mercury and light deflection near the Sun. The calculation result shows that Modified Newton¡¯s Gravity theory and General Relative theory have same accuracy to calculate planets orbit and light deflection. It also shows that the gravitational force between two objectives with high relative speed is a bit bigger than that with low relative speed. When this speed is up to light speed, the gravitational force is two times bigger than that with zero speed. %K MOND Theories of Gravity %K Mercury Precession %K Light Deflection %U http://www.oalib.com/paper/6760862