NASA's SPHEREx Mission Begins Mapping the Universe's Hidden History in Infrared

A NASA spacecraft is painting the cosmos in colors invisible to the human eye, capturing the universe’s history in unprecedented detail. The Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer, or SPHEREx, began its science mission on May 1, 2025, after launching in March. Orbiting Earth, it scans the entire sky, producing around 3,600 images daily to create a three-dimensional map of galaxies and stars.

Unlike telescopes that focus on specific cosmic targets, SPHEREx sweeps across every direction, collecting data in 102 infrared wavelengths. This approach allows scientists to explore vast questions, from the universe’s earliest moments to the ingredients that might spark life in distant star systems. The mission, managed by NASA’s Jet Propulsion Laboratory, promises to deliver insights over its 25-month survey.

The project’s ambition lies in its scope. By observing hundreds of millions of galaxies and over 100 million stars in the Milky Way, SPHEREx aims to unravel mysteries about cosmic inflation, galaxy evolution, and the chemical foundations of life. Its data, freely available to researchers worldwide, could redefine how we understand the universe’s past and future.

Yet, the mission operates in a complex landscape. NASA’s budget faces scrutiny, with debates over funding priorities and the role of private space ventures. SPHEREx’s success could hinge on sustained support, even as it builds on decades of international collaboration and open science.

SPHEREx’s primary goal is to investigate cosmic inflation, a rapid expansion that occurred a fraction of a second after the Big Bang. This event, when the universe grew a trillion-trillionfold, shaped the distribution of matter we see today. By mapping galaxies in 3D, SPHEREx will trace subtle patterns in their positions, offering clues about those fleeting, formative moments.

The mission’s infrared spectroscopy separates light into distinct wavelengths, revealing details about distant galaxies’ distances and compositions. This technique transforms flat sky maps into dynamic models, showing how the universe’s structure evolved over billions of years. Scientists hope these maps will clarify the physics of inflation, an event driven by energies unlike anything observed since.

Beyond cosmology, SPHEREx examines the collective glow of all galaxies, even those too faint to see individually. This glow, shifting over cosmic time, reflects the universe’s changing landscape. Researchers will use these measurements to study how galaxies formed and grew, connecting the universe’s infancy to its modern expanse.

Closer to home, SPHEREx turns its gaze to the Milky Way, hunting for water, carbon dioxide, and organic molecules in stellar nurseries. These compounds, essential for life, are thought to have seeded Earth’s oceans through ancient comets and meteorites. By mapping over 9 million interstellar clouds, the mission will reveal how these materials form and spread.

Recent studies have found nitriles, key building blocks for RNA, in molecular clouds at the Milky Way’s heart. SPHEREx’s survey could confirm whether such molecules are common across the galaxy, supporting theories that life’s ingredients are widespread. This work builds on decades of astrobiology research, from NASA’s Viking missions to modern Mars rovers.

The mission’s findings could reshape our understanding of habitability. By identifying regions rich in life-essential chemistry, SPHEREx may guide future searches for habitable worlds, complementing missions like the upcoming Habitable Worlds Observatory.

SPHEREx’s launch comes amid debates over NASA’s budget, set at $25.4 billion for 2025 but facing potential cuts. Some policymakers advocate focusing on deep space exploration, like the Artemis program, over broad scientific missions. Others highlight NASA’s economic impact, with $75 billion in output and 305,000 jobs supported in 2023, driven by programs like SPHEREx.

Supporters of scientific research argue that missions like SPHEREx drive innovation, from biotechnology to AI, with benefits rippling across industries. Critics, however, question the immediate returns of astrophysics compared to pressing terrestrial needs, proposing greater reliance on private space companies to share costs and risks.

International collaboration underpins SPHEREx, with contributions from South Korea and Taiwan alongside U.S. institutions. This global approach, seen in projects like the International Space Station, spreads costs and expertise, but geopolitical tensions and budget constraints could challenge future partnerships.

SPHEREx’s data will be publicly accessible through NASA’s Infrared Science Archive, aligning with the open science movement. This approach, rooted in projects like the Sloan Digital Sky Survey, empowers researchers worldwide to explore the mission’s findings, fostering discoveries in cosmology, stellar physics, and beyond.

The mission’s legacy will extend through its integration with other observatories, like the Nancy Grace Roman Space Telescope, set to launch later this decade. Together, they will deepen our grasp of the cosmos, proving the value of sustained investment in exploration.

As SPHEREx scans the sky, it embodies a human drive to understand our origins and place in the universe. Its maps, rich with data, will spark questions and answers for generations, bridging the vastness of space with the curiosity that propels us forward.