NASA's SPHEREx space telescope launched into orbit by a SpaceX Falcon 9 rocket

NASA's SPHEREx observatory is now in space for a two year year mission to create a 3D map of the entire celestial sky. The telescope left the ground on top of a Falcon 9 rocket from a launch pad in California, four years after NASA announced that a SpaceX flight will launch the mission, along with NASA's PUNCH (Polarimeter to Unify the Corona and Heliosphere) microsatellites. SPHEREx separated from SpaceX's vehicle at 12AM Eastern time on March 12 and will remain in low Earth orbit, where it will maintain a position relative to the sun that will remain the same throughout the year.

Every 98-minute orbit the observatory makes will allow it to view a 360-degree strip of the sky in both optical as well as near-infrared light. The telescope can capture more 360-degree strips as the Earth moves around the sun, enabling it to map the entire celestial sky within six months. SPHEREx was designed to image the entire sky every six months in two years, with its goal being to create a 3D map of over 450 million galaxies. The telescope will also image and gather information on over 100 million stars in the Milky Way.

SPHEREx's map is bound to be colorful: It will separate infrared light emitted by the stars and galaxies into 102 individual colors using a technique called spectroscopy. NASA likens it to the "way a prism splits sunlight into a rainbow." The agency says observing the objects in different colors will reveal various properties about them, such as their composition. For galaxies, their colors could help scientists determine their distance from our planet. The data SPHEREx provides will give scientists information about what happened right after the Big Bang and could provide evidence of cosmic inflation, or the rapid expansion of the early universe. SPHEREx will shed its telescope lens' protective cover in four days and will start its science operations in a little over a month once its temperature has cooled down. 

Meanwhile, the four PUNCH satellites, which will also take on a Sun-synchronous orbit, will map the sun's corona by taking polarized white-light images of the celestial object. It will gather data to help us better understand how the corona turns into solar wind, which could lead to accurate predictions of space weather events affecting spacecraft orbiting the Earth.