The data from Webb found the telltale signature of large organic molecules akin to smog and smoke —building blocks of the same cancer-causing hydrocarbon emissions on Earth that are key contributors to atmospheric pollution. However, Spilker says the implications of galactic smoke signals are much less disastrous for their cosmic ecosystems.
“These big molecules are actually pretty common in space,” Spilker explained. “Astronomers used to think they were a good sign that new stars were forming. Anywhere you saw these molecules, baby stars were also right there blazing away.”
The new results from Webb show that this idea might not exactly ring true in the early universe, according to Spilker.
“Thanks to the high-definition images from Webb, we found a lot of regions with smoke but no star formation, and others with new stars forming but no smoke,” Spilker added.
University of Illinois Urbana-Champaign graduate student Kedar Phadke, who led the technical development of the team’s Webb observations, noted that astronomers are using Webb to make connections across the vastness of space with unprecedented potential.
“Discoveries like this are precisely what Webb was built to do: understand the earliest stages of the universe in new and exciting ways,” Phadke said. “It’s amazing that we can identify molecules billions of light-years away that we’re familiar with here on Earth, even if they show up in ways we don’t like, like smog and smoke. It’s also a powerful statement about the amazing capabilities of Webb that we’ve never had before.”
The discovery is Webb’s first detection of complex molecules in the early universe — a milestone moment that Spilker sees as a beginning rather than an end.
“These are early days for the Webb Telescope, so astronomers are excited to see all the new things it can do for us,” Spilker said. “Detecting smoke in a galaxy early in the history of the universe? Webb makes this look easy. Now that we’ve shown this is possible for the first time, we’re looking forward to trying to understand whether it’s really true that where there’s smoke, there’s fire. Maybe we’ll even be able to find galaxies that are so young that complex molecules like these haven’t had time to form in the vacuum of space yet, so galaxies are all fire and no smoke. The only way to know for sure is to look at more galaxies, hopefully even further away than this one.”
The team’s paper, “Spatial variations in aromatic hydrocarbon emission in a dust-rich galaxy,” can be viewed online along with related figures and acknowledgements.
JWST is operated by the Space Telescope Science Institute under the management of the Association of Universities for Research in Astronomy under NASA contract NAS 5-03127. The South Pole Telescope is supported by the National Science Foundation, the Department of Energy and the United States Antarctic Program.