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How did WMAP and Planck measurements help determine the age and shape of the universe?

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Astronomy Hubble Space Telescope, photographed by the space shuttle Discovery.

The Wilkinson Microwave Anisotropy Probe (WMAP) and the Planck satellite were instrumental in advancing our understanding of the universe by mapping the cosmic microwave background (CMB) with unprecedented precision.123

By measuring minute temperature fluctuations in the CMB—which represent density variations in the early universe—these missions allowed scientists to analyze the conditions present approximately 380,000 years after the big bang. Through these observations, researchers were able to accurately determine the age of the universe to be 13.8 billion years and map its composition, including the proportions of dark matter, dark energy, and atoms.1432

While WMAP provided foundational data on these cosmic parameters, the Planck satellite, launched in 2009, mapped the CMB with even greater sensitivity and higher angular resolution. This enhanced detail enabled scientists to refine measurements of the universe's structure and evolution, including the study of gravitational lensing and the Sunyaev-Zeldovich effect, which further constrained models regarding the geometry and expansion of the universe.123