This experiment grew out experience of the previous Tenerife Experiment with the need to go to smaller angular scales with greater sensitivity.

The Ramsden theodolite for the first time divided angular scales accurately to within a second of arc.

This angular scale corresponds to a multipole moment .

By the end of the year 2000 the experiment provided the most accurate measurements of the cosmic background radiation (CMB) fluctuations on small angular scales.

Thus, measurements of this angular scale allow an estimation of Ω.

This effect is the predominant source of fluctuations in the CMB for angular scales above about ten degrees.

As of 2010, several experiments to improve measurements of the polarization and the microwave background on small angular scales are ongoing.

The angular scale of the first peak determines the curvature of the universe (but not the topology of the universe).

The physics of how photons are scattered by free electrons (Thomson scattering) induces polarization anisotropies on large angular scales.

These measurements will determine the angular scale of the sound horizon for galaxies at different redshifts.