Skip to main content

This peculiar galaxy has one spiral arm brighter than the others

This image taken with the NASA/ESA Hubble Space Telescope features NGC 7678 – a galaxy with one particularly prominent arm, located approximately 164 million light-years away in the constellation of Pegasus (the Winged Horse). With a diameter of around 115,000 light-years, this bright spiral galaxy is a similar size to our own galaxy (the Milky Way) and was discovered in 1784 by the German-British astronomer William Herschel.
This week’s Hubble/ESA Picture of the Week features NGC 7678 — a galaxy located approximately 164 million light-years away in the constellation of Pegasus (The Winged Horse). With a diameter of around 115 000 light-years, this bright spiral galaxy is a similar size to our own galaxy (the Milky Way) and was discovered in 1784 by the German-British astronomer William Herschel. ESA/Hubble & NASA, A. Riess et al.

The scientists using the Hubble Space Telescope have shared another beautiful space image, this time of a strangely asymmetrical galaxy located in the constellation of Pegasus.

Most galaxies, including our own Milky Way, are broadly symmetrical unless they have undergone a dramatic event such as a merger with another galaxy which has pulled them into an unusual shape. But occasionally you find an unusually asymmetrical galaxy, like the one pictured in this Picture of the Week from the Hubble Space Telescope.

Galaxy NGC 7678, located 164 million light-years away, is an asymmetrical oddity in which one of its spiral arms is notably brighter than the others. The arms of a spiral galaxy are regions where new stars are often born, as dust and gas clump together and eventually forms together under the force of gravity. These newly born stars burn very brightly, leaving pinpricks of blue light throughout the arms where they are located.

In this galaxy, one of the arms has much more matter in it than the others, meaning it is much more massive and more stars are forming there, which is why it appears brighter. This distinctive feature sets it apart from other galaxies, such as our own. At around 115,000 light-years across, this galaxy is roughly the same size as our Milky Way, and it is also of the barred spiral type.

This galaxy is listed in an astronomical catalog created by Halton Arp in 1966 with the delightful name, “The Atlas of Peculiar Galaxies.” It is listed alongside six other galaxies which also have unevenness between their arms, categorized as “spiral galaxies with one heavy arm.”

Editors' Recommendations

Georgina Torbet
Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…
Hubble captures a formation of galaxies neatly lined up
An interacting galaxy system known as Arp-Madore 2105-332, that lies about 200 million light-years from Earth in the constellation Microscopium.

Sometimes, Hubble or other telescopes will capture two or more galaxies that are in the process of merging -- called interacting galaxies. These huge collisions can warp one or both of the galaxies, twisting them into strange shapes. The results of such collisions can be catastrophic, with one of the galaxies being destroyed. Or they can be creative, with one larger galaxy being formed from the two merging galaxies.

However, sometimes galaxies that appear very close in images are not actually interacting. Sometimes, they merely appear to be close when seen from Earth, but they can actually be thousands of light-years apart. That's the case with a previous Hubble image showing two overlapping galaxies.

Read more
Webb and Hubble work together to image the Christmas Tree Galaxy Cluster
This panchromatic view of galaxy cluster MACS0416 was created by combining infrared observations from NASA’s James Webb Space Telescope with visible-light data from NASA’s Hubble Space Telescope. To make the image, in general the shortest wavelengths of light were color-coded blue, the longest wavelengths red, and intermediate wavelengths green. The resulting wavelength coverage, from 0.4 to 5 microns, reveals a vivid landscape of galaxies that could be described as one of the most colorful views of the universe ever created.

Different telescopes work at different wavelengths, meaning they can observe different objects in the sky -- and when data from various telescopes is combined, it can make for stunning views that would be impossible to get from any one instrument. That's the case with a beautiful new image of a cluster of thousands of galaxies that combines data from both the Hubble Space Telescope and the James Webb Space Telescope to create a stunning and colorful view.

This panchromatic view of galaxy cluster MACS0416 was created by combining infrared observations from NASA’s James Webb Space Telescope with visible-light data from NASA’s Hubble Space Telescope. To make the image, the shortest wavelengths of light were color-coded blue, the longest wavelengths red, and intermediate wavelengths green. The resulting wavelength coverage, from 0.4 to 5 microns, reveals a vivid landscape of galaxies that could be described as one of the most colorful views of the universe ever created. NASA, ESA, CSA, STScI, Jose M. Diego (IFCA), Jordan C. J. D'Silva (UWA), Anton M. Koekemoer (STScI), Jake Summers (ASU), Rogier Windhorst (ASU), Haojing Yan (University of Missouri)

Read more
This peculiar galaxy has two supermassive black holes at its heart
The billion-year-old aftermath of a double spiral galaxy collision, at the heart of which is a pair of supermassive black holes.

As hard as it is to picture, with billions or even trillions of galaxies in the universe, entire galaxies can collide with each other. When that happens, one galaxy can be destroyed or the two can merge into one. But even in the case of galaxy mergers, the effects of the collision are often visible for billions of years afterward.

That's shown in a recent image taken by the Gemini South observatory, which shows the chaotic result of a merger between two spiral galaxies 1 billion years ago.

Read more