In this composite image of the spiral galaxy NGC 4921, formed from 80 individual Hubble Space Telescope exposures, more distant galaxies are visible through the spiral's translucent dust ring.
NASA, ESA and K. Cook (Lawrence Livermore National Laboratory)
Join Our Community of Science Lovers!
On supporting science journalism
If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
In this composite image of the spiral galaxy NGC 4921, formed from 80 individual Hubble Space Telescope exposures, more distant galaxies are visible through the spiral's translucent dust ring. NGC 4921 is classified as an anemic spiral—its star formation rate is lower than most galaxies of its type, hence its relative transparency in this view. The spiral is found in the Coma galaxy cluster, a grouping of more than 1,000 galaxies about 320 million light-years away in the northern constellation Coma Berenices.
It’s Time to Stand Up for Science
If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.
I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.
If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.