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| Cosmic Distance Calibration |
 Title text: This is the biggest breakthrough since astronomers noticed that the little crosshairs around red giant stars starting to burn helium are all the same size. |
Explanation
The comic interprets the UI labels next to the stars as actual objects in space, which is absurd,[citation needed] among other reasons because they could be observed from multiple distances. If these labels were to become astrophysical objects in reality, it would quickly result in major changes to the universe. As each of these labels would need to be clearly visible from an observatory, they would require monstrous size, maybe even big enough to collapse into black holes when pointing to stars farther away. They would also create a sudden lack of need for themselves, as the stars would be gravitationally attracted to their respective labels and promptly destroyed.
Labels like this are often generated by outdated or specialized software and tend to use bad fonts and small font sizes. The software developer may have expected all images to be exported at the standard resolution at the time of development and set the font size to pixel size in the code.
The label on the billboard appears to be pointing to a star in the spiral galaxy M106 (also known as "Messier 106" and "NGC 4258"), located between 22 and 25 million light-years away from earth.
The title text suggests that the "crosshairs" around red giant stars, indicating those starting to burn helium, are standardized objects in space. One of such crosshairs can be seen in the comic, around the previously mentioned marked star. These crosshairs, like the labels in the comic, are just graphical UI marks. Its reference to red giant stars starting to burn helium is because of how, in real life, all red giant stars at that stage have the same absolute brightness. This allows their distance to be determined because the observed luminosity is a simple inverse-distance-squared falloff from a known original value. This is referred to as the "tip of the red-giant branch" (TRGB) distance calculation method, referring to the red-giant region of the Hertzsprung–Russell diagram. This allows estimation of distances not only to the stars themselves, but also to distant galaxies that contain them.
Transcript
- [Ponytail is standing behind a lectern, pointing with a stick towards a large screen behind her. The screen has three parts where two of them zooms further in to parts of the upper and largest part, a rectangular image of intergalactic space, with light gray, not black background. In this image there are a couple of large spiral galaxies, towards the upper left and lower right part of the image. And then there are more than 30 white dots (stars or far of galaxies) There also seems to be some unreadable labels next to many of the stars. One of the stars have a crosshair around it, with four lines going up, down, left and right from the star. This star has a circle around it, and inside the circle the background is darker gray. From the circle lines goes down to the next part of the image showing a round zoomed-in on this star. In this zoom in, it becomes clear that there is indeed a label (in three lines) beneath this crosshair star. The label is stil hard to read, but not impossible, but some part of the label is partially cut off. Then there is another circle around the label, with black background, with lines going down from this to another zoome-in showing the labels three lines of text, so it is now readable, although even more of the text is partially cut off. The three dots below indicate where the text is not complete.]
- [First zoom in:]
- M106 0-06832
- Distance:
- 23.6163 MLY (27...
- [Second zoom in:]
- M106 0-06...
- Distance:
- 23.6163 MLY...
- [Caption below the panel:]
- Cosmology News: New telescopes are finally powerful enough to read the little labels next to stars showing how far away they are.
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