NGC 1365 (MIRI Image - Annotated)

This image of the nearby galaxy NGC 1365, captured by Webb’s Mid-Infrared Instrument (MIRI) shows compass arrows, scale bar, and color key for reference.

The north and east compass arrows show the orientation of the image on the sky. Note that the relationship between north and east on the sky (as seen from below) is flipped relative to direction arrows on a map of the ground (as seen from above). At the lower right is a scale bar labeled 8,000 light-years, 30 arcseconds. The length of the scale bar is approximately one-fifth the total width of the image. Below the image is a color key showing which MIRI filters were used to create the image and which visible-light color is assigned to each filter. In this image of NGC 1365, blue, green, and red were assigned to Webb’s MIRI data at 7.7, 10 and 11.3, and 21 microns (the F770W, F1000W and F1130W, and F2100W filters, respectively).

Scientists are getting their first look with the NASA/ESA/CSA James Webb Space Telescope’s powerful resolution at how the formation of young stars influences the evolution of nearby galaxies. NGC 1365, observed here by Webb’s Mid-Infrared Instrument (MIRI) is one of a total of 19 galaxies targeted for study by the Physics at High Angular resolution in Nearby Galaxies (PHANGS) collaboration.

As revealed by the MIRI observations of NGC 1365, clumps of dust and gas in the interstellar medium have absorbed the light from forming stars and emitted it back out in the infrared, lighting up an intricate network of cavernous bubbles and filamentary shells influenced by young stars releasing energy into the galaxy’s spiral arms.

Webb’s exquisite resolution also picks up several extremely bright star clusters not far from the core and newly observed recently formed clusters along the outer edges of the spiral arms.

Additionally, the Webb images provide insights into how the orbits of stars and gas vary depending on where they form, and how this results in the population of older clusters outside the inner ring of star formation.

NGC 1365 is a double-barred spiral galaxy that lies about 56 million light-years away from Earth. It’s one of the largest galaxies currently known to astronomers, spanning twice the length of the Milky Way.

MIRI was contributed by ESA and NASA, with the instrument designed and built by a consortium of nationally funded European Institutes (The MIRI European Consortium) and NASA’s Jet Propulsion Laboratory, in partnership with the University of Arizona.

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