Two space science missions are promising, Steinhardt said. SNAP would find about 2,000 supernovae a year, enough to significantly close the error bars on calculations of the universe's rate of expansion. The mission is not yet funded. MAP may detect small variations in the amount of quintessence across the sky as seen in ripples in the microwave background, remnant radiation from when the universe was 300,000 years old. Chuck Bennett, a MAP project leader at NASA Goddard Space Flight Centre, is rather excited.
Quintessence makes very specific predictions.
To see if it is there or not is a no brainer. To get an exact value, well, that's a little harder. At issue is how well MAP can measure the factors in the quintessence equation, such as the mass density of the universe, its geometry and rate of expansion, and the neutrino contribution. Steinhardt certainly has a good track record. He was one of the originators of the inflation theory and predicted an accelerating universe back in 1995.