It's Even More Full of Stars

The discovery that elliptical galaxies have many more red dwarf stars than the Milky Way means that the universe might have three times as many total stars as previously thought. Cynthia Graber reports

Illustration of a Bohr atom model spinning around the words Science Quickly with various science and medicine related icons around the text

Join Our Community of Science Lovers!

To many who stare up at the heavens, the stars may seem simply uncountable. Of course that’s not the attitude of astronomers. But they’ve made a discovery that means there are probably a lot more stars in the universe than they thought.

Red dwarfs are stars that are only 10 to 20 percent as massive as our sun. They’re so faint that astronomers weren’t able to detect them in any galaxies other than our own Milky Way, and neighboring ones.

So researchers used sensitive instruments at the Keck Observatory in Hawaii. They found faint signatures of these red dwarf stars in eight massive elliptical galaxies relatively close to us—between 50 million and 300 million light-years away. And they discovered that these galaxies were home to 20 times as many red dwarfs as there are in the Milky Way.


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.


The finding means leads astronomers to believe that there may be three times as many stars in the universe as they’d previously theorized. The research was published in the journal Nature. [Pieter van Dokkum and Charlie Conroy, A substantial population of low-mass stars in luminous elliptical galaxies]

And a recently discovered exoplanet orbiting a red dwarf had some Earth-like qualities. Lead researcher Pieter van Dokkum says there could be trillions of Earths orbiting the ubiquitous red dwarfs.

—Cynthia Graber

[The above text is an exact transcript of this podcast]

Scientific American is part of the Nature Publishing Group.

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.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe