The Korea AeroSpace Administration and the Korea Astronomy and Space Science Institute (KASI) on the 19th released the first all-sky map video captured by the space telescope SPHEREx, jointly developed with NASA. The video is significant as the "first space map" made by dividing the entire sky into 102 infrared wavelengths for spectroscopic observation.
SPHEREx was launched on Mar. 12 this year and began full-scale observations on May 1. It then scanned the entire sky for about six months to complete the all-sky map. Because the light SPHEREx captures is in the infrared range invisible to the human eye, the released video visualizes the observations by converting them into visible colors.
The video shows in color the infrared traces of celestial bodies and matter captured by SPHEREx. Light from stars appears in blue, green, and white tones; hot hydrogen gas appears mainly in blue; and cosmic dust appears in red.
The method of producing the all-sky map is also unique. As SPHEREx orbits Earth about 14.5 times a day, it crosses the North and South Poles, passing over the polar regions. Each day it takes about 3,600 images along ring-shaped swaths of the sky, and as Earth revolves around the sun, the field of view shifts slightly. Repeating this process for about six months completes a 360-degree mosaic video that stitches together the entire sky.
The core of the observations is spectroscopy. SPHEREx uses linearly variable spectral filters specially designed for six detectors to measure 102 wavelength bands simultaneously. The all-sky data obtained this way is expected to be widely used for major science missions, including unraveling cosmic history, studying the formation and evolution of galaxies, and exploring water and ice linked to the origin of life.
The mission is led by NASA's Jet Propulsion Laboratory (JPL), and an international team including 10 institutions in the United States and the research team of Jeong Ung-seop at KASI will participate in data analysis. During SPHEREx's primary two-year mission, the joint team plans to conduct three additional all-sky surveys and build a "sensitivity-enhanced 3D integrated map" by combining the data. The dataset will be released for free use by both scientists and the general public.
Shawn Domagal-Goldman, acting head of NASA's Astrophysics Division, emphasized the scale and potential of SPHEREx data and said it will open opportunities for new discoveries to researchers worldwide. Kang Gyeong-in, head of the space science exploration division at the Korea AeroSpace Administration (KASA), also said, "Based on SPHEREx observation data that Korea participated in, domestic researchers will be able to play key roles on a range of topics, including not only cosmic ice but also active galactic nuclei and small solar system bodies."