The word "alighting up on" means to descend or come to a stop on a surface. Antonyms for this term include "ascending," which means to move or climb upward, and "flying," which means to move through the air with wings or an engine. Other antonyms include "taking off," which means to leave the ground and begin a flight, and "hovering," which means to stay in one place in the air without moving in any direction. Finally, "stopping" could also be considered an antonym, as it means to come to a complete halt, rather than simply landing or descending.