NASA’s Webb Throws Light On The Evolution Of Galaxies and Black Holes

The holiday classic movie “It’s a Wonderful Life” has a scene that prominently features Stephan’s Quintet, a visual collection of five galaxies. Today, a new perspective on Stephan’s Quintet is provided by NASA’s James Webb Space Telescope.

Webb’s greatest photograph to date, this massive mosaic spans nearly one-fifth of the Moon’s diameter. It is made up of about 1,000 different image files and has over 150 million pixels.

The data from Webb offer fresh perspectives on how galaxy evolution may have been influenced by galactic interactions in the early cosmos.

Webb reveals previously unseen characteristics in this galaxy group thanks to its strong infrared vision and exceptionally high spatial resolution. The image is adorned with dazzling starburst regions and clusters of millions of newborn stars.

What Are The Observations?

Gravitational interactions cause several of the galaxies to produce sweeping tails of gas, dust, and stars. The most spectacular image, taken by Webb as one of the galaxies, NGC 7318B, slams through the cluster, showing enormous shock waves.

What Is The Hickson Compact Group 92?

The Hickson Compact Group 92 comprises the five galaxies that make up Stephan’s Quintet (HCG 92). Only four of the so-called “quintet” of galaxies are actually in close proximity to one another and engaged in a cosmic dance.

NGC 7320, the fifth and leftmost galaxy, is clearly in the foreground when compared to the other four. The distance between NGC 7320 and Earth is 40 million light-years, but the distance between the other four galaxies—NGC 7317, NGC 7318A, NGC 7318B, and NGC 7319—is roughly 290 million light-years.

In comparison to further galaxies that are billions of light-years away, this is still quite close in cosmic terms. These relatively close-by galaxies are being studied to better comprehend the structures of the far more distant universe.

The Significance Of Galaxy Mergers

Astronomers have a front-row view of the galaxy mergers and interactions that are so essential to galaxy evolution because of this close proximity.

Rarely do scientists get to observe in such great detail how the gas in these interacting galaxies is being disturbed and how they induce star formation in one another. A great “laboratory” for researching these processes that are essential to all galaxies is Stephan’s Quintet.

This type of tight group may have been more prevalent in the early cosmos when its superheated, infalling material may have fed extremely energizing black holes.

What Is This NGC 7319?

The biggest galaxy in the group, NGC 7319, still has a supermassive black hole that is 24 million times as big as the Sun as its active galactic center. It actively draws in matter and emits light with 40 billion Sun’s worth of energy.

With the help of the Mid-Infrared Instrument and Near-Infrared Spectrograph (NIRSpec), Webb thoroughly investigated the active galactic nucleus (MIRI).

What Is This ‘IFU’?

The Webb team received a “data cube,” or collection of photographs showing the spectral properties of the galactic center, from these sensors’ integral field units (IFUs), which are a combination of a camera and spectrograph.

The IFUs give researchers the ability to “slice and dice” the information into several images for in-depth analysis, much like medical magnetic resonance imaging (MRI).

How Did Webb Observe These Hot Gasses?

In order to see the hot gas close to the active black hole and assess the speed of brilliant outflows, Webb had to cut through the cloud of dust surrounding the nucleus. The telescope observed these black hole-driven outflows in unprecedented detail.

Webb was able to distinguish individual stars in NGC 7320, the leftmost and nearest galaxy in the visible cluster, as well as the galaxy’s luminous core.

Is There Something Else That Webb Discovered?

A bonus discovery made by Webb was a massive sea of thousands of far-off background galaxies that resembled Hubble’s Deep Fields.

The data from Webb will deliver a wealth of useful, new information when combined with the most accurate infrared image of Stephan’s Quintet yet obtained from MIRI and the Near-Infrared Camera (NIRCam). For instance, it will aid in the understanding of the rate of growth and feeding of supermassive black holes.


Additionally, Webb detects star-forming regions far more clearly and can now investigate radiation from the dust at a level of precision that was previously not conceivable. Stephan’s Quintet, which is in the constellation Pegasus, was found in 1877 by a French astronomer named Édouard Stephan.

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