Stunning Photo by James Webb Transforms a Far Away Galaxy Into a Sparkling Christmas Ornament – ​​Teach Me About Science

This image is dominated by NGC 7469, a luminous spiral galaxy regarding 90,000 light-years across. (Credit: ESA/Webb, NASA & CSA, L. Armus, AS Evans).

Some 220 million light-years from Earth, something spectacular has just been photographed by the NASA/ESA James Webb Space Telescope (JWST): it is a brilliant galaxy that might be the perfect complement to the Christmas tree. The image shows NGC 7469, a luminous spiral galaxy regarding 90,000 light-years across that lies regarding 220 million light-years from Earth in the constellation Pegasus. Also partially shown at bottom left is its companion galaxy IC 5283.

To obtain this view, the MIRI, NIRCam and NIRspec instruments on board the telescope were used to obtain images and spectra of NGC 7469 in unprecedented detail. The astronomers explain that the image contains a series of details that have never been seen before, including very young star-forming clusters, as well as pockets of very hot and turbulent molecular gas, and direct evidence of the destruction of small dust grains at a few hundreds of light-years from the nucleus, demonstrating that the active galactic nucleus (AGN) is impacting the surrounding interstellar medium.

“NGC 7469 harbors an active galactic nucleus (AGN), which is an extremely bright central region dominated by light emitted by dust and gas falling into the galaxy’s central black hole,” ESA collaborators write. “This galaxy offers astronomers a unique opportunity to study the relationship between AGN and stellar activity, as this particular object hosts an AGN that is surrounded by a stellar ring at a distance of just 1,500 light-years.”

Studying this type of objects is not an easy task, they are generally surrounded by dust, which makes observation difficult. NGC 7469 is one of the best-studied AGNs in the sky, but the compact nature of this system and the presence of a large amount of dust have made it difficult for scientists to study it in detail. Now, with Webb, astronomers can explore the galaxy’s stellar ring, the central AGN, and the gas and dust between them; the infrared view of this new observatory allows easy penetration into dense clouds of gas and dust that was previously impossible.

NGC 7469 is quite special and striking. It features a six-pointed star that aligns perfectly with the heart of the galaxy, but it’s too beautiful to be real. The bright star in the center is actually an imaging artifact known as a diffraction spike, caused by the bright AGN and the physical structure of the telescope.

“Diffraction spikes are patterns produced when light bends around the sharp edges of a telescope. Webb’s primary mirror is composed of hexagonal segments containing edges once morest which light is diffracted, giving rise to six bright peaks. There are also two shorter, weaker spikes, created by diffraction from the vertical strut that helps support Webb’s secondary mirror.”

Webb orbits the Sun 1.5 million kilometers from Earth, at a place called the second Lagrange point. There, far from the interference of Earth’s light, Webb focuses his attention on the early universe, exoplanet atmospheres, and other science, using a deployable telescope almost 21 feet in diameter, regarding three times the aperture of Hubble with 2.4 meters.

See the image and detailed description in the ESA website.

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