This is both excellent new analysis — making use of older data, alongside new… AND a very accessible metaphor, for the non-technical thermodynamic / astro-sciences crowd.

The authors of this new study explain that an enduring mystery of star formation was that very hot gasses were seen (skiers hopping off the chair-lifts at the mountain-top) — but only a small portion of those gasses were cooling enough to form stars (skiers turning gracefully back into the lift line, at the bottom of the mountain).

Well, using both X-ray data, mapped onto infrared in the same expanse of the Phoenix cluster, the teams discovered that very large structures were interacting at “mid-mountain” — where a good chunk of the skiers pull into a bistro, on the mountainside, before skiing on down, to catch the chair back up again. This is where they. . . “cool“. Here’s that (at NASA) — and a far more technical paper on it, from the journal Nature:

…Researchers using NASA’s [JWST] have finally solved the mystery of how a massive galaxy cluster is forming stars at such a high rate. The confirmation from JWST builds on more than a decade of studies using NASA’s Chandra X-ray Observatory and Hubble Space Telescope, as well as several ground-based observatories.

The Phoenix cluster, a grouping of galaxies bound together by gravity 5.8 billion light-years from Earth, has been a target of interest for astronomers due to a few unique properties. In particular, ones that are surprising: a suspected extreme cooling of gas and a furious star formation rate despite a roughly 10 billion solar mass supermassive black hole at its core. In other observed galaxy clusters, the central supermassive black hole powers energetic particles and radiation that prevents gas from cooling enough to form stars. Researchers have been studying gas flows within this cluster to try to understand how it is driving such extreme star formation….

“We can compare our previous studies of the Phoenix cluster, which found differing cooling rates at different temperatures, to a ski slope,” said Michael McDonald of the Massachusetts Institute of Technology in Cambridge, principal investigator of the program. “The Phoenix cluster has the largest reservoir of hot, cooling gas of any galaxy cluster — analogous to having the busiest chair lift, bringing the most skiers to the top of the mountain. However, not all of those skiers were making it down the mountain, meaning not all the gas was cooling to low temperatures. If you had a ski slope where there were significantly more people getting off the ski lift at the top than were arriving at the bottom, that would be a problem!”

To date, in the Phoenix cluster, the numbers weren’t adding up, and researchers were missing a piece of the process. [The team] has now found those proverbial skiers at the middle of the mountain, in that it has tracked and mapped the missing cooling gas that will ultimately feed star formation. Most importantly, this intermediary warm gas was found within cavities tracing the very hot gas, a searing 18 million degrees Fahrenheit, and the already cooled gas around 18,000 degrees Fahrenheit….

“In the mid-infrared wavelengths detected by [JWST], the neon VI signature was absolutely booming,” explained Michael Reefe, also of the Massachusetts Institute of Technology, lead author on the paper published in Nature. “Even though this emission is usually more difficult to detect, the new scope’s sensitivity in the mid-infrared cuts through all of the noise….”

And so, those Leadvillian “missing skiers” — taking an afternoon in the sun, and eating croissants and sipping hot cocoa at mid mountain… are hidden no longer. Smile.

नमस्ते