3d spaceshooter with 3 missions.Protect scientific facilities from alien attack.

3D spaceshooter with 3 missions. You just finished the space academy and are ready to join the Space Guards, an union for protecting scientific research of the cosmos. The first task is to protect the spacestation X5, which is directed by the brilliant young scientist Dr. Sophia Cardes. It sounded like an easy job, just pushing some asteroids around but suddenly an unknown enemy starts to attack. The second mission takes you to Skycity, a flying research project, hovering in the orbit. Because you did an excellent job at spacestation X5 you get an recommendation and finally a job at Skycity. It is under thread by several different spacecrafts of the enemy, whose motivations still are not clear. But it seems that they want to stop mankind from exploring the space. Finally the battle on Mars. The enemy attacks with tanks and later with airborne crafts too. It becomes clear that mankind is at war. Under all circumstances an evacuation is to be avoided but how long can you remain?