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| SNEWS |
 Title text: People say setting of fireworks indoors is dangerous, but I looked at their energy release and it's like 10^-40 foe; totally negligible. |
Explanation
Ponytail is showing Hairy her bedroom. Hairy asks about the large device on the ceiling, and Ponytail explains that it is part of the SNEWS (SuperNova Early Warning System). This provides advance notice of supernovae by detecting neutrinos (tiny particles that travel near the speed of light, rarely interacting with matter). Neutrinos are produced in large quantities during the collapse of the star core, which occurs hours before the main photon production which makes them visible to the eye. She explains this gives astronomers warning, allowing them to observe the event with telescopes and other instruments.
Hairy reasonably assumes that the device is either a detector, forming part of the SNEWS, or some kind of telescope to be used in the event the SNEWS goes off. However, Ponytail explains that it is a fireworks launcher — presumably linked into the detection network and triggered if it registers an observation — for the purposes of waking her up so she can witness the supernova herself. This is a very bad idea, for a multitude of reasons. Reckless use of fireworks is known for causing significant property damage and personal injury, even when used outdoors; launching fireworks inside the house means causing an explosion in a confined area, guaranteeing that it will hit the building, maximizing the opportunity to ignite something flammable on the structure, and containing, and therefore amplifying, the sound of the burst (which can already deafen people who are too close). Understandably, Hairy leaves to sleep at his own house.
Some people aren't easily woken up by a simple alarm clock, especially if it is in reach and has a "snooze" function where a button will silence the alarm for several minutes before it beeps again. The similar sounds of "snooze" and SNEWS may be part of the joke.
Ponytail is being hyperbolic, because even if all astronomers were interested in supernovae, not every individual or observatory will be immediately situated to view a particular point in the sky. For example, they may need to wait for the Earth's rotation, causing the phenomenon to "rise" in the east. Others may be located at unfavorable latitudes where the object will never appear above the Earth's horizon. It may also take some time before the supernova reaches an apparent magnitude that is visible during the daytime. Which would be particularly disappointing for everyone (on Earth) if it all happens to a star currently too close to conjunction with the Sun to see, in spite of the advanced neutrino warning.
Since historical supernovae have been visible from 6 months to nearly 2 years, it would be unlikely that Ponytail sleeps through a new one in its entirety, although there would still be significant cachet for any astronomer lucky enough to be able to legitimately say that they had seen the 'first light' at the earliest opportunity. It would also be difficult for her to not sleep through part of the supernova, for the same reason.
The title text is a play on the tremendous amount of energy released by a supernova. The foe is an unofficial unit of energy equal to 10^44 Joule (but named directly from initials in the original quantity of "ten to the fifty-one ergs", involving a pre-SI measurement of energy), which is approximately on the order of the usual amount of energy released by a supernova. In comparison, human-scale amounts of energy — even relatively significant ones such as firework detonations — are negligible. This ignores the fact that energy releases that are "negligible in comparison to a supernova" can still be easily fatal to humans; even the largest man-made nuclear explosion is approximately twenty-seven orders of magnitude less than the baseline 'foe' value. The described "10-40 foe" is equal to 10 kJ, the energy released by the complete combustion of about 0.6 g of table sugar (sucrose), or the decomposition of about 6 g of nitrocellulose.
Transcript
- [Ponytail is walking into her room. The room has a bed, a set of drawers and a large sci-fi device mounted on the ceiling. Hairy is standing in the room, pointing up at the device.]
- Hairy: What's that device?
- Ponytail: Part of the supernova early warning system.
- Ponytail: There hasn't been a Milky Way supernova in over a century.
- Ponytail: Astronomers don't want to miss the next one.
- [Close up of Ponytail, now sitting on the end of the bed]
- Ponytail: 20 years ago, we set up a supernova alert system using neutrino detectors.
- Ponytail: It should give us a few hours' advance notice.
- [In a frame-less panel the view zooms back out, showing Ponytail and Hairy.]
- Ponytail: If it ever goes off, every astronomer on earth will scramble to point their equipment at the sky.
- Hairy: Oh, OK. So is that a detector? Or some kind of telescope?
- [The panel moves to the right, showing Hairy walking away. Ponytail is still on the end of the bed, raising a clenched fist for dramatic effect.]
- Ponytail: Fireworks launcher.
- Ponytail: I refuse to sleep through a supernova.
- Hairy: I think I'll spend the night at my place instead.
Trivia
The word "off" is misspelled as "of" in the title text.
This comic was published on the eve of the Chinese New Year or Lunar New Year, which is reckoned by the new moon appearing at this time of year. Celebrations throughout Asia and communities worldwide include setting off firecrackers and launching fireworks.
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