Missions & Experiments

Space missions and ground-based experiments that probe the cosmic microwave background and the early universe’s evolution.

How Do Galaxy Surveys Detect Baryon Acoustic Oscillations?

| Missions & Experiments |

Baryon acoustic oscillations (BAOs) are a fossil imprint of sound waves in the early universe, appearing as a subtle clustering pattern in galaxy distributions. Galaxy surveys detect this pattern by measuring the correlation function or power spectrum, revealing a characteristic scale that serves as a standard ruler for cosmic expansion. This guide explains the detection method, its cosmic significance, and the full timeline of cosmic evolution from the Planck epoch to today.

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What Are the Challenges of Observing the First Stars?

| Missions & Experiments |

The first stars, known as Population III, ended the cosmic dark ages and seeded the universe with heavy elements. Observing them directly is one of astronomy’s greatest challenges because they are extremely distant, faint, short-lived, and their light is redshifted far into the infrared. This guide explains the obstacles, the cosmic epochs that set the stage, and how missions like JWST are pushing the observational frontier.

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What Is the CMB-S4 Experiment? A Guide to the Universe’s First Moments

| Missions & Experiments |

CMB-S4 was a proposed next-generation ground-based observatory designed to study the cosmic microwave background and probe the universe’s earliest moments. Although canceled in 2025, its scientific goals and technical innovations continue to shape cosmology. This article explains the experiment, the cosmic epochs it would have explored, and why the CMB remains a cornerstone of modern astrophysics.

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How LISA Will Detect Gravitational Waves from the First Black Holes

| Missions & Experiments |

The Laser Interferometer Space Antenna (LISA) is poised to detect gravitational waves from the first generation of black holes—seeds of supermassive black holes formed in the early universe. This article explains how LISA will probe cosmic epochs from the Planck era to reionization, and why these observations will transform our understanding of structure formation.

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What Is the Simons Observatory? A Window into the Cosmic Microwave Background

| Simons Observatory |

The Simons Observatory is a next-generation cosmic microwave background experiment in the Atacama Desert, designed to probe the earliest moments of the universe—from inflation to the formation of the first stars and galaxies. Using a suite of small and large aperture telescopes, it maps the oldest light in the cosmos with unprecedented precision, targeting questions about the universe’s origin, composition, and evolution.

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