The goal is to look for evidence of something called inflation that would have happened less than a billionth of a billionth of a second after the Big Bang. Proof of this would be the way galaxies are positioned in the universe, and SPHEREx will help scientists to map them in 3D relative to each other. Then they can study these charts for patterns that are potentially caused by inflation. At the same time, the instrument will help to find out how the first galaxies formed the stars.
The space telescope will also scan the stars in its own galaxy for water ice and frozen organic molecules, the building blocks of life on Earth. The idea is that water ice attaches to dust grains in gas clouds around galaxies. The stars form inside these clouds, then the planets form from the remains of matter that surround them. “The ice in these disks could seed the planets with water and other organic molecules,” NASA wrote. “In fact, the water in Earth’s oceans probably started out as interstellar ice.”
Prior to Phase C, the SPHEREx team had to perform a preliminary design review and prove to NASA that they could actually build it. The team will spend 29 months finalizing the design and construction components, before moving on to the next phase when they are assembled and tested. SPHEREx is set to launch in a window between June 2024 and April 2025, if all goes according to plan – which is not, of course, a given.