The project is truly an international effort, and the largest scientific instrument ever to be installed on the orbiting outpost.
It's called the Alpha Magnetic Spectrometer, and it's already stowed inside Endeavour's cargo bay, awaiting its chance to begin the search for dark matter and antimatter far away in the universe. Dark matter is unseen, unlike the stars, and makes up 90 percent of the universe we know so far.
Scientists will be able to study the information the AMS collects from galaxies millions of light years away, and based on theories of the origin of the universe, there must be an equal amount of matter and antimatter.
The project is the brainchild of Dr. Samuel Ting, of the Massachusetts Institute of Technology, who is heading a team from 60 international institutes from 16 countries under the umbrella of the U.S. Department of Energy.
"The space station, which is already there, has the power to support it," said Ting.
The AMS will also operate the first ever superconducting, cryogenic magnet in space, and will gather information on cosmic rays and the radiation they produce. That, in itself, is a major danger for astronauts headed to Mars. A spacecraft needs adequate protection, and the measurements made by the scanner hope to shed some light on what will be required.
The AMS will collect data 24 hours a day, 7 days a week, 365 days a year. Researchers on the ground will gather it, with hopes of determining the origins of our universe.
The shuttle will also be ferrying spare parts and a storage platform, items that will help the space station function past the year 2020.