SPHEREx and PUNCH Missions Launched  

NASA’s SPHEREx & PUNCH Missions were launched into space together on 11March 2025 abroad a SpaceX Falcon 9 rocket.  

SPHEREx (Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer) mission aims to study the origins of universe and the history of galaxies, and to search for the ingredients of life in our galaxy. The SPHEREx Space Telescope or observatory will be a cosmic mapmaker. It will create a 3D map of the entire celestial sky every six months, providing a wide perspective to complement the works of James Webb and Hubble space telescopes that observe smaller sections of the sky in more detail.  SPHEREx will use spectroscopy to measure the distance to 450 million galaxies in the nearby universe whose large-scale distribution was influenced by cosmic inflation about 13.8 billion years ago. Inflation caused the universe to expand in size a trillion-trillionfold in a fraction of a second after the big bang. Spectroscopy can reveal the composition of cosmic objects, hence SPHEREx will survey Milky Way for hidden reservoirs of frozen water ice and other molecules, like carbon dioxide, that are essential to life. The mission will also measure the total collective glow of all the galaxies in the universe, providing new insights about how galaxies were formed and evolved over cosmic time.  

PUNCH (Polarimeter to Unify the Corona and Heliosphere) mission is made of four satellites. Aim of PUNCH mission is to study how the Sun’s outer atmosphere becomes the solar wind. It will make global, 3D observations of the inner solar system and the Sun’s outer atmosphere, the corona, to learn how its mass and energy become a stream of charged particles blowing outward from the Sun in all directions. The mission will explore the formation and evolution of space weather events such as coronal mass ejections, which create storms of energetic particle radiation that endanger spacecraft and astronauts. 

Both SPHEREx and PUNCH missions will operate in a low Earth, Sun-synchronous orbit over the day-night line (the fuzzy line that separates day and night, also called the terminator or the grey line or the twilight zone) so the Sun always remains in the same position relative to the spacecraft. The telescope of SPHEREx needs to be shielded from the Sun’s light and heat and the PUNCH satellites need to have a clear view in all directions around the Sun.  

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References:  

1. NASA Launches Missions to Study Sun, Universe’s Beginning. Posted 12 March 2025. Available at https://www.nasa.gov/news-release/nasa-launches-missions-to-study-sun-universes-beginning/  

2. SPHEREx. Available at https://www.jpl.nasa.gov/missions/spherex/ 

3. An All-Sky Spectral Survey. Available at https://spherex.caltech.edu/ 

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