Due to the dramatic technological progress of human beings, we have expanded the area of activity to space, and many space colonies have been constructed for living in space. We humans' immigration to space seemed to be all right. However, in space history X085, the 16th colony ORBIT farthest from the earth declared independence and launched an indiscriminate attack on the earth side. People born in space were dissatisfied with the difference in treatment with the earth side.
To protect the peace of space, the Earth Government has established the Space Defense Force ALTAIR. They succeeded in rejecting the ORBIT attack. However, the conflict between the two armies became deeper. In space history X122, an emergency warning sounded at the base of ALTAIR on the earth side. The re-armed ORBIT launched an attack on the Earth side again. Now, the battle for the fate of the earth and the universe begins!