(Az-Zukhuruf) 43 : 84
وَهُوَ الَّذِي فِي السَّمَاءِ إِلَٰهٌ وَفِي الْأَرْضِ إِلَٰهٌ ۚ وَهُوَ الْحَكِيمُ الْعَلِيمُ
And He is the only Deity in heaven and the only Deity on the earth; and He is the Wise, the Knower.
Allah is the single Deity not only on the earth, but also on any planet in the universe. See explanation 23: 116-117; 28: 88; and 41: 5-7.