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| Star Formation |
 Title text: It's ok, I still have some nice, cool gas clouds that aren't collapsing. As long as nothing ionizes them, I can continue to enjoy their ... HEY! NO!!! |
Explanation
This comic depicts a simplified model of how structure forms in the universe, then pushes it to an absurd extreme. In cosmology, small density variations in the early universe grow over time: regions with slightly higher density attract more matter via gravity, eventually forming gas clouds, stars, and galaxies. Pressure, driven by temperature, resists collapse, so the evolution of a cloud depends on the balance between gravitational attraction and internal pressure; this is often described by the Jeans instability criterion.
In the first panel, the on-screen narrator (with a passing resemblance to the time-travelling sphere), and apparent creator of the universe, describes pressure waves moving through gas and causing it to clump, which is broadly accurate. In the second, the clouds begin to collapse under gravity as more gas falls in, again matching real astrophysical processes. However, the third panel exaggerates the outcome: as collapse proceeds, the gas heats up (via compression and radiation processes), increasing pressure and often slowing or fragmenting the collapse rather than causing a runaway “explosion.” The comic instead imagines a catastrophic, accelerating collapse, akin to forming a black hole or triggering an energetic outburst. In reality, only under specific conditions, such as in the formation of direct collapse black holes, can gas clouds avoid fragmenting and collapse rapidly into massive objects.
The final panel humorously frames this as the narrator lamenting the destruction of their “beautiful clouds,” as the process has gone out of control and produced an intense central object (likely a star or black hole) instead of stable clouds.
The title text continues this joke by referencing the importance of ionization. “Cool” gas clouds (low temperature, neutral gas) can remain stable or collapse slowly. If they are ionized (for example, by nearby stars emitting ultraviolet radiation), the gas heats up, increasing pressure and preventing or disrupting collapse. The narrator hopes to preserve some calm, neutral clouds but then reacts in horror as something ionizes them, ruining the delicate balance and ending their ability to “enjoy” stable gas clouds.
Transcript
- [A glowing dot is in a field of clouds, speaking to itself.]
- Dot: I think I did a good job with this universe.
- Dot: Pressure waves dance through gas clouds.
- Dot: They clump together and then pressure pushes them apart.
- [The dot observes some more densely gathering of clouds.]
- Dot: Oh weird, that big clump of clouds is staying together.
- Dot: Their gravity is overcoming the pressure and more gas is falling in.
- [More of the increasingly fragmentary clouds start to fall into a nascent star.]
- Dot: It's not stopping!
- Dot: The heat is rising but the collapse is only accelerating!
- Dot: I messed up bad. I messed up bad.
- [There is now a shining star in place of the dense field of clouds, with a few small clouds only at a distance.
- Dot: NOOOOOOOO!!!
- Dot: My beautiful clouds!
- Dot: Ruined! It's all ruined!
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