If you have to leave your house unoccupied, say during a vacation, it can leave you very worried about what could go wrong. Now imagine if that "house" were orbiting the Earth!

That's the problem facing the organization that operates the International Space Station. It began last week with the explosion of an unmanned Russian supply rocket [pictured at left]. That rocket is very similar to the one used to ferry astronauts to and from the Station. Russia's space agency (Roscosmos) announced on Monday that the explosion was caused by a problem with the spaceship's third stage. The investigation is continuing, but weather problems and limited equipment in the isolated area where the rocket went down are hampering the probe.

The six-person crew on the Station has return craft at hand, so they can come home safely. But re-staffing the Space Station may be difficult. Three of the astronauts were scheduled to return later this month, when replacements were to be launched. That flight will likely be postponed until the problem with the Russian rocket can be repaired. The remaining crew is scheduled to return to Earth in November. Weather problems at the remote site where Russian rockets are launched may prevent sending new crew members until next spring, if the flights are delayed too long.

NASA is currently de-comissioning the retired Space Shuttle fleet, before turning them over to museums around the country, and has no other craft available to send astronauts to the Station.

The agency that operates the Space Station says it could be controlled from Earth for a while, as long as nothing goes wrong on board [and such breakdowns are not uncommon]. It says its first priority is that of the current crew, then the Station and any future astronauts scheduled to go there.

I'm no scientist, but maybe NASA should keep a Shuttle available for just such emergencies. Some museum would be dissappointed, but it would be a little more security for astronauts. What's your take on all this? Let us kno