A switch-out of the magnet for a much anticipated particle physics experiment on the International Space Station will force NASA to delay the final flight of the space shuttle until at least November, and change which orbiter and crew will fly the final space shuttle mission. The $2 billion Alpha Magnetic Spectrometer was scheduled to head to the ISS in July of this year, but recent thermal vacuum tests showed the superconducting magnet that was originally planned to power the experiment would have only worked 2-3 years. An ordinary magnet, which doesn’t need to be super-cooled will last for a decade or more – and given the ISS has been given a longer life, it seems to be the best option. “I don’t think it’s correct to go there for three years where there is a chance to do physics for 18 years,” said Dr. Samuel Ting, AMS Principal Investor, in an article in the New York Times.
NASA officials said today they still are evaluating the exact day in November, as they must schedule the mission to fit around other resupply and crew flights to the ISS, with the Russian Progress and Soyuz vehicles.
The AMS is designed to search for various types of unusual matter by measuring cosmic rays, and will help researchers study the formation of the universe and search for evidence of dark matter and antimatter.
Changing the magnet means the AMS won’t arrive at Kennedy Space Center before August and shuttle workers need time to get the payload ready to fly inside the shuttle’s cargo bay.
The upcoming flight of the shuttle Atlantis (STS-132) remains on schedule for launch no earlier than May 14. But Endeavour was scheduled for the AMS flight in July, which will now move to no earlier than November. Discovery’s STS-133 flight (bringing up the Leonardo MPLM as a permanent storage module) stays on the schedule for September 16. So while the schedule changes, numerical order is restored!
Another possible change to the shuttle schedule would be if the decision to fly what is called STS-335, the Launch On Need mission, a shuttle ready to go as a rescue ship for the last scheduled mission. Many shuttle supporters say since Atlantis would be ready to fly that it should fly. No decision has yet been made, however.
Even if the final flight or flights get delayed into 2011, funding is not a problem, as Congress anticipated possible delays and provided funds for shuttle operations into early next year.
Liquid helium would have been used cool the superconducting magnet’s temperature to near absolute zero. But tests showed the helium would dissipate withing 2-3 years, leaving the seven-ton experiment useless. The ISS has been extended to at least 2020, and possibly as long as 2028.
Sources: New York Times, Orlando Sentinel