To learn how our Universe grew up, we have to look at large numbers of galaxies at all distances to find out. Good thing we have JWST!
This image shows a tiny sliver of the COSMOS-Web survey, with galaxies at a variety of distances along with a portion of a rich cluster of galaxies, at right, of this image.
Key Takeaways
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Here in our modern Universe, we know what the Milky Way and many nearby galaxies look like: with stars, gas, dust, globular clusters, black holes and more. But how did they get to be this way? -
That follow up question requires not just looking at the snapshot of the Universe we get by looking nearby, but rather a look all throughout cosmic history, at the common, uncommon, and rare galaxies all across the Universe. -
Thanks to JWST, and particularly with its wide-field but still deep observing programs like COSMOS-Web, we’re uncovering profound insights, and learning to ask new follow-up questions, like never before.
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Travel the universe with Dr. Ethan Siegel as he answers the biggest questions of all.
It’s no secret that the Universe and the objects present within it, as we see them all today, have changed over time as the Universe has grown up over the past 13.8 billion years. Galaxies are larger, more massive, more evolved, and are richer in stars but fewer in number than they were back in the early stages of cosmic history. By looking farther and farther away, we can see the Universe as it was at earlier times, but we’re going to be limited in many ways: by how deep our telescopes can see, by what wavelengths they’re capable of seeing, and by what small fraction of the sky they’re capable of observing.
That’s why an observing program like COSMOS-Web, the largest, widest-field JWST observing program to date, is so important. It isn’t just revealing galaxies as they are nearby (at late times), at a variety of intermediate distances (and earlier times), and at ultra-large distances (and the earliest times of all), but due to its wide-field nature, is revealing galaxy types of varying abundances: the common-type galaxies, galaxies that are representative of more uncommon varieties, and even significant numbers of rare galaxies. And it’s this aspect of galaxy evolution that makes me so proud and lucky to welcome Dr. Olivia Cooper to the podcast.
Olivia is a recently-minted PhD who works as part of the COSMOS-Web team, specializing in galaxy evolution and using JWST data — along with data from other world-class observatories — to investigate how the galaxies in our Universe grew up, and what that can teach us about our own cosmic past. It truly is a banger of an episode that you’ll want to listen to every minute of, so tune in and dive deep into the depths of the distant Universe on our latest adventure of the Starts With A Bang podcast!
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Travel the universe with Dr. Ethan Siegel as he answers the biggest questions of all.
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