The James Webb Telescope has changed our understanding of the universe in less than a year of its scientific operations as it marks its first anniversary in the vacuum of space. The spacecraft has beamed back a new image of a glowing six-pointed star to mark Christmas.
The image shows NGC 7469, a luminous, face-on spiral galaxy approximately 90 000 light-years in diameter that lies roughly 220 million light-years from Earth. The image also contains galaxy IC 5283, which is partly visible in the lower left portion of this image.
A prominent feature of the image is the striking six-pointed star that perfectly aligns with the heart of NGC 7469. However, it’s not real. It is an imaging artifact known as a diffraction spike, caused by the bright, unresolved active galactic nuclei. Diffraction spikes are patterns produced as light bends around the sharp edges of a telescope.
The European Space Agency in a release with the image said that the galaxy is home to an active galactic nucleus (AGN), which is an extremely bright central region that is dominated by the light emitted by dust and gas as it falls into the galaxy’s central black hole.
The galaxy has recently been studied as part of the Great Observatories All-sky LIRGs Survey (GOALS) Early Release Science program. The study is aimed to better understand the physics of star formation, black hole growth, and feedback in four nearby, merging luminous infrared galaxies.
“This galaxy provides astronomers with the unique opportunity to study the relationship between AGNs and starburst activity because this particular object hosts an AGN that is surrounded by a starburst ring at a distance of a mere 1500 light-years,” the European Space Agency (ESA), said in a statement.
The presence of massive amounts of dust has made it difficult for scientists to achieve both the resolution and sensitivity needed to study this relationship in the infrared. However, the Webb telescope has paved the way to explore this unseen world. “With Webb, astronomers can explore the galaxy’s starburst ring, the central AGN, and the gas and dust in between,” ESA added. ‘
Astronomers used Webb’s MIRI, NIRCam, and NIRspec instruments to obtain images and spectra of NGC 7469 in unprecedented detail. Analysis of the data revealed the presence of young star-forming clusters never seen before, as well as pockets of very warm, turbulent molecular gas, and direct evidence for the destruction of small dust grains within a few hundred light-years of the nucleus.