3212: Little Red Dots

2026-04-29T06:02:51Z

2A02:587:4D60:BE00:57:F4C1:63E6:FED8: /* Explanation */ Added a relevant link (to another xkcd comic) where perceived size is explained.

{{comic
| number = 3212
| date = February 25, 2026
| title = Little Red Dots
| image = little_red_dots_2x.png
| imagesize = 634x306px
| noexpand = true
| titletext = After a lot of analysis, I've determined that they're actually big red dots; they're just very far away.
}}

==Explanation==
The {{w|Little red dot (astronomical object)|little red dot}}s that the comic refers to are something of an astronomical mystery, discovered by the {{w|James Webb Space Telescope}} (a.k.a. "JWST"). They may be powered by [https://www.cam.ac.uk/research/news/astronomers-detect-oldest-black-hole-ever-observed very, very old black holes] from 400-700 million years after the Big Bang, with the light from when they were young. The comic purports to give the responses of several different experts in unrelated fields when asked to identify them:
* According to the {{w|Entomology|entomologists}} (scientists who study insects and related arthropods) [represented by [[Megan]]], they are {{w|Clover mite | clover mites}} (''Bryobia praetiosa'') — very small [[Red Spiders|red arachnids]].
**[[Red Spiders]] were a common theme in early ''xkcd''.
* According to the {{w|Computer_science|computer scientists}} [represented by [[Knit Cap]]], they are {{w|defective pixel|stuck pixels}} — pixels that do not work properly, and are stuck to one single color (red in this case). This is {{w|Hot pixel (telescopes)|a plausible concern}}, but presumably should already be handled through calibration processes. Interestingly enough though, this answer is the one most likely of all the possible explanations in the comic, ignoring the true conclusion of being actual distant objects.
* According to the {{w|Dermatology|dermatologists}} (doctors who specialize in skin disorders) [represented by [[Ponytail]]], they are {{w|Cherry angioma|cherry angiomas}} — harmless, non-cancerous skin growths made of clusters of dilated capillaries, appearing as bright red, smooth, or slightly raised spots.
* According to the {{w|Graphic_design|graphic designers}} [represented by [[Hairy]]], these are not "red dots" but are colors of type [https://www.colorhexa.com/d73b3e Jasper] (<span style="color:#d73b3e">●</span> #d73b3e) or [https://www.colorhexa.com/e34234 Vermillion] (<span style="color:#e34234">●</span> #e34234, sometimes called Cinnabar).

Quite obviously, all of these, if not completely incorrect, are fully unrelated to astronomy, and instead represent instances of the {{w|law of the instrument}}.

Part of the punchline is the shift in focus: instead of trying to identify the object, the designer is nitpicking the description of "red dot." Additionally, the graphic designer is also requesting [[Cueball]]'s {{w|Color_calibration|color settings}}, implying they believe the reason Cueball calls them "red" is due to poor display settings, and not due to using the common term for the color. There is a certain amount of insight here, as the JWST only observes orange to far-infrared light. This is to enable it to see very distant objects, whose blue and ultraviolet emissions have been {{w|redshift|redshifted}} into longer wavelengths. Converting observed wavelengths into rest-frame wavelengths is a process subject to error, as is {{w|false color|falsely-coloring}} the object so that it may be visualized by human eyes.

In the title text, Randall claims to have analyzed the "little red dots" and determined that they are actually very large but distant objects. This is not a startling revelation, since the JWST telescope is mostly only used to look at very distant objects in space, and just to be visible at all at these distances these 'dots' would need to be very large; this is due to the [https://www.youtube.com/watch?v=MMiKyfd6hA0 phenomenon] of [https://www.youtube.com/watch?v=pvnKXOGYKM8&t=30s relative perceived size], where larger objects that are further away ([[2622: Angular Diameter Turnaround|usually]]) appear to be the same size as smaller ones that are closer to the viewer. The punchline here is that someone who has performed a lot of analysis would be expected to have a result that was not already obvious, but anyone looking at a telescope image of deep space would already be assuming that it depicts large objects very far away, not small objects close to the telescope. The theme of astronomers unsure of the size of objects spotted in a telescope was previously mentioned in [[2359: Evidence of Alien Life]].

The (possible) issue of a 'stuck pixel', except of a different hue, was previously visited in [[1246: Pale Blue Dot]].

A comic with a similar theme of specialists giving an answer relating to their field is [[3127: Where Babies Come From]].

==Transcript==
:[Caption above all the panels:]
:Astronomers asking researchers from different departments to help them identify the "little red dots" in JWST images:

:[In each panel, Cueball stands at the left of an easel displaying a black image with three red dots on it. At the right of the easel in each panel is a different character looking at the image on the easel and commenting on it. At the top of each panel is a caption indicating the type of researcher commenting on the image.]

:Caption: Entomologists
:Megan: Clover mites.

:Caption: Computer scientists
:Knit Cap: Stuck pixels.

:Caption: Dermatologists
:Ponytail: Cherry angiomas.

:Caption: Graphic designers
:Hairy: No, those are vermillion, or maybe jasper.
:Hairy: Can I see your color settings?

{{comic discussion}}<noinclude>

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Knit Cap]]
[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring Hairy]]
[[Category:Comics with color]]
[[Category:Astronomy]]
[[Category:Telescopes]]
[[Category:Biology]]
[[Category:Computers]]
[[Category:Medicine]]
[[Category:Graphic designers]]

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3212: Little Red Dots