Woolly galaxy captured by Hubble has an enormous bulge in the middle

By Georgina Torbet June 29, 2020

Hubble has captured another beautiful image of a distant galaxy. This time, the star of the image is the galaxy NGC 2775, which is extremely distant, located 67 million light-years away. It is part of the Antilia-Hydra Cloud of galaxies, located in the constellation of Cancer, and is part of the Virgo Supercluster.

This particular galaxy is notable for its delicate spiral arms, which are feather-like. In astronomical terms, these wavy arms are referred to as “flocculent,” meaning woolly or fluffy.

spiral pattern shown by the galaxy known as NGC 2775 — The spiral pattern shown by the galaxy in this image from the NASA/ESA Hubble Space Telescope is striking because of its delicate, feathery nature. These “flocculent” spiral arms indicate that the recent history of star formation of the galaxy, known as NGC 2775, has been relatively quiet. There is virtually no star formation in the central part of the galaxy, which is dominated by an unusually large and relatively empty galactic bulge, where all the gas was converted into stars long ago. ESA/Hubble & NASA, J. Lee and the PHANGS-HST Team, Acknowledgement: Judy Schmidt (Geckzilla)

“Millions of bright, young, blue stars shine in the complex, feather-like spiral arms, interlaced with dark lanes of dust,” the Hubble scientists wrote in the announcement sharing the new image. “Complexes of these hot, blue stars are thought to trigger star formation in nearby gas clouds. The overall feather-like spiral patterns of the arms are then formed by shearing of the gas clouds as the galaxy rotates. The spiral nature of flocculents stands in contrast to the grand design spirals, which have prominent, well defined-spiral arms.”

As well as its wavy arms, another unusual feature of this galaxy is its unexpectedly large bulge. Most spiral galaxies have a bulge in the center, where many stars are tightly packed together around the central area of the galaxy, compared to the more sparsely populated arms. And the arms tend to fall along a flat plane, while the bulge sticks out from the top and bottom of the galaxy.

In the case of NGC 2775, the bulge is not only larger than would be typical, but it is also relatively empty and hosts virtually no star formation. There is a relatively small amount of gas in the bulge, which scientists believe could be evidence that at one time in the galaxy’s history there was a large amount of supernovae activity in the area.

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Georgina Torbet

Space Writer

Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…

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