'Interstellar glaciers': NASA's SPHEREx maps vast galactic ice regions

Interstellar ice as life's reservoir

One of SPHEREx's main goals is to map the chemical signatures of various types of interstellar ice. This ice includes molecules like water, carbon dioxide, and carbon monoxide, which are vital to the chemistry that allows life to develop. Researchers believe these ice reservoirs, attached to the surfaces of tiny dust grains, are where most of the universe's water is formed and stored. The water in Earth's oceans—and the ices in comets and on other planets and moons in our galaxy—originates from these regions.

"These vast frozen complexes are like 'interstellar glaciers' that could deliver a massive water supply to new solar systems that will be born in the region," said study co-author Phil Korngut, the instrument scientist for SPHEREx at Caltech in Pasadena, California. "It's a profound idea that we are looking at a map of material that could rain on nascent planets and potentially support future life."

How SPHEREx sees the invisible ices

Thanks to its spectral capabilities, SPHEREx can measure the amounts of various ices and molecules, such as polycyclic aromatic hydrocarbons, in and around molecular clouds, helping scientists better understand their composition and environment.

A three-color image of the CygX region constructed from SPHEREx mosaics. Credit: The Astrophysical Journal (2026). DOI:10.3847/1538-4357/ae5180

Water ice, shown as bright blue structures. Credit: NASA

Dark lanes of interstellar dust, shown in different wavelengths. Credit: NASA