NASA has published the first cosmic map generated using observations from its SPHEREx space telescope. In particular, these observations include 102 wavelengths in the near-infrared. What NASA has defined as 102 colors offer a wealth of different information about the observed objects, valuable in a variety of cosmological studies. The wealth of information is such that NASA treats them as if they had obtained 102 different maps.
The top image (NASA/JPL-Caltech) shows the complete map obtained, with infrared emissions generated mainly by dust (red) and hot gas (blue), key ingredients in the formation of new stars and planets.
Launched on March 11, 2025, the Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer (SPHEREx) space telescope aims to conduct an astrophysical investigation through global observation of the sky. Its spectroscope allows it to obtain information on the observed objects that can be used in various types of astronomical investigations.
Infrared emissions are the most common in the universe, which is why so many space telescopes specialize in observing in this electromagnetic band. Each instrument has specific characteristics designed to conduct certain types of studies: James Webb has unparalleled power and sensitivity, but its observations are focused on a small field of view, while SPHEREx was designed to map the sky and therefore have a much wider field of view. In the past, NASA conducted this type of mapping with WISE (Wide-field Infrared Survey Explorer), but SPHEREx offers many more colors, so much so that NASA mentions 102 maps, one for each detected color.
The cosmic map published by NASA was created using observations conducted over a period of about six months. This is already a significant achievement, but this is just the beginning. From its Sun-synchronous orbit, the SPHEREx space telescope circles Earth 14.5 times a day, capturing 3,600 images of a single strip of sky. Its field of view changes daily, and in six months it covers the entire sky. This means that, after completing its first global observation, it begins the next one. During its two-year primary mission, it’s expected to complete four scans and generate three more cosmic maps.
The combination of the various wavelengths detected allows for the generation of maps that reveal different details of the observed objects. These maps, in turn, can be combined with observations conducted with other instruments, sometimes operating in other electromagnetic bands, to obtain even more comprehensive information. The SPHEREx space telescope is already proving its worth, and the data collected is already being analyzed for various cosmological studies.
The bottom image (NASA/JPL-Caltech) shows the map without the dust and gas components, making stars and galaxies more visible.
