NASA Eyes Launching SPHEREx Sky-Mapping Mission in Early 2025

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The observatory will lend insight into what happened after the big bang, measure the glow of galaxies near and far, and search the Milky way for building blocks of life.

NASA and SpaceX are targeting late February 2025 for the launch of the agency’s next astrophysics observatory, SPHEREx. Short for Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer, SPHEREx will launch aboard a SpaceX Falcon 9 rocket from Vandenberg Space Force Base in California.

About the size of a subcompact car, SPHEREx will enter a polar orbit around Earth and create a map of the entire sky in 3D, taking images in every direction, like scanning the inside of a globe. The map will contain hundreds of millions of stars and galaxies, showing them in 102 colors (each a different wavelength of light).

Scientists will use SPHEREx’s all-sky map to achieve the mission’s three key science goals. The first is to shed light on a cosmic phenomenon called inflation, a brief but powerful cosmic event when space itself increased in size by a trillion-trillionfold less than a second after the big bang. The observatory will measure the distribution of hundreds of millions of galaxies to improve understanding of what drove inflation and of the physics behind this event.

The SPHEREx mission will also measure the collective glow from galaxies near and far, including light from hidden galaxies that haven’t been individually observed. This data will provide a more complete picture of all the objects and sources radiating in the universe.

Its third key science goal is to search the Milky Way galaxy for icy granules of water, carbon dioxide, and other essential building blocks of life. The mission will help scientists discover the location and abundance of these icy compounds in our galaxy, giving them a better sense of how likely they are to be incorporated into newly forming planets.

Launching as a secondary payload on the same Falcon 9 rocket as SPHEREx will be NASA’s PUNCH mission (Polarimeter to Unify the Corona and Heliosphere). Led by Southwest Research Institute’s office in Boulder, Colorado, and managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland, PUNCH is a constellation of four small satellites heading to low Earth orbit that will make global, 3D observations of the Sun’s corona to learn how the mass and energy there become solar wind.

NASA’s Launch Services Program, based at the agency’s Kennedy Space Center, manages the launch service for the SPHEREx and PUNCH missions.