International Space station:

Briefly explain the purpose of the International Space Station, and list the name of all countries involved in building and operating it. The ISS is almost complete. What is the name of the last module to be added and when will it be launched? Once completed, how long will it stay in operation and what are the deorbit plans for the Station?
2Mars Exploration Rovers (MER):

What are the main differences between Mars Exploration Rover (MER) and Mars Pathfinder missions? And what is the major discovery of Mars Exploration Rover (MER) mission.