The ISS is scheduled to be completed in 2011. The station is expected to be operational for another 10 years after that. Crews of astronauts will exchange out during that time. However, how that will happen is still unclear. The U.S. space shuttle fleet is being retired next year after 30 years of service. NASA's plans for returning to the Moon aboard the new Orion CEV spacecraft have been placed on hold as the Obama administration has cancelled the program. Although the Orion CEV spacecraft itself is still being developed, the Ares launch vehicle was cancelled. So, the future of the U.S. manned space program is uncertain at this time. NASA continues to develop new rocket technology to replace the shuttle. But exactly when this will be ready is unknown.
Once the shuttle fleet is retired, the United States will have no way of putting astronauts into space for a while. So, manned missions to the ISS will have to be transported using the Russian Soyuz spacecraft and resupplied using the Progress supply ships.
The ISS is not without its problems. With any machine as large and complex as the ISS, equipment breaks down and requires maintenance. However, given the projected price tag (more than $100 billion), many people have asked the question, "Is the ISS worth the money?" The criticism surrounds these basic points:
- Is the science information gained worth the high price tag?
- The ISS has little purpose in the future of space exploration. Critics have said that it exists to give the shuttles some place to go and the shuttles exist to service the ISS. The ISS isn't a launch platform to the moon, Mars or planets, no new rocket technology is being developed aboard it, and it does not fit into any long range plans of space exploration.
- The ISS budget diverts funds away from highly successful unmanned space probes and space telescopes, which produce valuable scientific information.
- The ISS budget diverts funds away from other manned space projects like missions to the moon or Mars.
Only time will tell about the benefits and costs of the ISS. In the meantime, it remains a marvel of space construction and the longest manned space mission undertaken.