NASA has signed up to join the European Space Agency's (ESA's) Euclid mission, a space telescope due to launch in 2020 and designed to investigate dark matter and dark energy.
Euclid will be placed in an orbit around the sun-Earth Lagrange point L2: a location where the gravitational pull of the sun and Earth precisely equal the force required for the Euclid spacecraft, to stay relatively stationary as seen from the sun.
Here, it will spend six years mapping the locations and measuring the shapes of up to two billion galaxies across more than one-third of the sky.
"NASA is very proud to contribute to ESA's mission to understand one of the greatest science mysteries of our time," says John Grunsfeld, associate administrator for NASA's Science Mission Directorate at the agency's Headquarters in Washington.
NASA will contribute 16 state-of-the-art infrared detectors and four spare detectors for one of two science instruments planned for Euclid.It's also nominated three US science teams for the Euclid Consortium, an international body of 1,000 members who will oversee development of the instruments, manage science operations, and analyze data.
Euclid will map dark matter, believed to account for about 85 percent of the total amount of matter in the universe. It was firstpostulated in 1932, but still has never been detected directly. Dark matter interacts with ordinary matter through gravity and binds galaxies together.
Euclid will use two techniques to study the dark universe, both involving precise measurements of galaxies billions of light-years away. The observations, says the team, will yield the best measurements yet of how the acceleration of the universe has changed over time, providing new clues about the evolution and future of the cosmos.