Webb and Hubble Combine to Create Most Colorful View of Universe

This panchromatic view of galaxy cluster MACS0416 was created by combining infrared observations from NASA’s James Webb Space Telescope with visible-light data from NASA’s Hubble Space Telescope. To make the image, in general the shortest wavelengths of light were color-coded blue, the longest wavelengths red, and intermediate wavelengths green. The resulting wavelength coverage, from 0.4 to 5 microns, reveals a vivid landscape of galaxies that could be described as one of the most colorful views of the universe ever created.

MACS0416 is a galaxy cluster located about 4.3 billion light-years from Earth, meaning that light we see now left the cluster shortly after the formation of our solar system. This cluster magnifies the light from more distant background galaxies through gravitational lensing. As a result, the research team has been able to identify magnified supernovae and even very highly magnified individual stars.

Those colors give clues to galaxy distances: The bluest galaxies are relatively nearby and often show intense star formation, as best detected by Hubble, while the redder galaxies tend to be more distant, or else contain copious amount of dust, as detected by Webb. The image reveals a wealth of details that are only possible to capture by combining the power of both space telescopes.

In this image, blue represents data at wavelengths of 0.435 and 0.606 microns (Hubble filters F435W and F606W); cyan is 0.814, 0.9, and 1.05 microns (Hubble filters F814W, and F105W and Webb filter F090W); green is 1.15, 1.25, 1.4, 1.5, and 1.6 microns (Hubble filters F125W, F140W, and F160W, and Webb filters F115W and F150W); yellow is 2.00 and 2.77 microns (Webb filters F200W, and F277W); orange is 3.56 microns (Webb filter F356W); and red represents data at 4.1 and 4.44 microns (Webb filters F410M and F444W).

This image of galaxy cluster MACS0416 highlights one particular gravitationally lensed background galaxy, which existed about 3 billion years after the big bang. That galaxy contains a transient, or object that varies in observed brightness over time, that the science team nicknamed “Mothra.” Mothra is a star that is magnified by a factor of at least 4,000 times. The team believes that Mothra is magnified not only by the gravity of galaxy cluster MACS0416, but also by an object known as a “milli-lens” that likely weighs about as much as a globular star cluster.

This side-by-side comparison of galaxy cluster MACS0416 as seen by the Hubble Space Telescope in optical light (left) and the James Webb Space Telescope in infrared light (right) reveals different details. Both images feature hundreds of galaxies, however the Webb image shows galaxies that are invisible or only barely visible in the Hubble image. This is because Webb’s infrared vision can detect galaxies too distant or dusty for Hubble to see. (Light from distant galaxies is redshifted due to the expansion of the universe.) The total exposure time for Webb was about 22 hours, compared to 122 hours of exposure time for the Hubble image.