BOOMERanG experiment
The BOOMERanG experiment (Balloon Observations Of Millimetric Extragalactic Radiation and Geophysics) measured the cosmic microwave background radiation (CMB) during three sub-orbital (high altitude) balloon flights. The first was a test flight over North America in 1997. The two subsequent flights were over Antarctica in 1998 and 2003. It was the first experiment to make large, high fidelity images of the CMB temperature anisotropies. Together with experiments like Saskatoon, TOCO, MAXIMA, and others, the Boomerang data from 1997 and 1998 determined the angular diameter distance to the surface of last scattering with high precision. When combined with complementary data regarding the value of Hubble's constant, the Boomerang data determined that the geometry of the Universe to be flat (see [1] and [2]) , supporting the supernova evidence for the existence of dark energy. The 2003 flight of Boomerang resulted in extremely high signal to noise maps of the CMB temperature anisotropy, and a measurement of the polarization of the CMB.