Leo P (NIRCam image)

This image from the NASA/ESA/CSA James Webb Space Telescope shows a portion of the Leo P dwarf galaxy (stars at lower right represented in blue). Leo P is a star-forming galaxy located about 5 million light-years away in the constellation Leo. A team of scientists collected data from about 15,000 stars in Leo P to deduce its star formation history. They determined that it went through three phases: an initial burst of star formation, a “pause” that lasted several billion years, and then a new round of star formation that is still continuing.

The image from Webb’s NIRCam (Near-Infrared Camera) combines infrared light at wavelengths of 0.9 microns (represented in blue), 1.5 microns (green), and 2.77 microns (red). The stars in Leo P appear blue in comparison to the background galaxies for several reasons. Young, massive stars that are common in star-forming galaxies are predominantly blue. Leo P also is extremely lacking in elements heavier than hydrogen and helium, and the resulting “metal-poor” stars tend to be bluer than Sun-like stars. A bubble-like structure at bottom center is a region of ionized hydrogen surrounding a hot, massive O-type star.