502: Dark Flow

2026-02-17T13:45:45Z

2A00:23C8:3309:F01:250F:FA3F:D0CE:BFBF: /* Explanation */ Grammar correction

{{comic
| number = 502
| date = November 10, 2008
| title = Dark Flow
| image = dark_flow.png
| titletext = The Pioneer anomaly is due to the force of my love.
}}

==Explanation==
This comic is about {{w|astronomy}} and the {{w|Your Mom}} jokes that have become increasingly widespread in urban parlance. [[Beret Guy]] is reading a research paper presumably discussing {{w|Dark Flow}}, an observed anomaly in the motions of the galaxies that some theorize is caused by an unobservable sibling universe or similarly supermassive object beyond the edge of the visible universe. [[Cueball]] sees this as an opportunity to make yet another Your Mom joke, implying that Beret Guy's mother is fat.

But apparently, Beret Guy's mother is dead, or at least missing, and he takes the joke seriously. He looks toward the sky and wishes that his mom pull harder so that he could be with her. The joke has been turned onto itself.

The title text is a continuation of Beret Guy's thoughts and refers to another science phenomenon that has been observed in space, the {{w|Pioneer Anomaly}}. The ''{{w|Pioneer 10}}'' and ''{{w|Pioneer 11}}'' spacecraft had been slowed down by an (at the time) unknown force as they exited the solar system, which he says is caused by the force of his love, probably toward his mom. This force has since been explained entirely in 2012 by the probes being decelerated by thermal radiation.

In [[2310: Great Attractor]], thanks to "galactic motion and how many dimensions [his] bones have", the more local {{w|Great Attractor}} is pulling Beret Guy so hard that he can sleep on vertical surfaces when it is close to the horizon.

==Transcript==
:[Beret Guy is sitting at a computer, and Cueball is sitting in an armchair, reading either a book or a newspaper.]
:Beret Guy: According to this A.S.T. paper, every galaxy is being pulled toward one area of the sky.

:[Only Cueball.]
:Beret Guy [off-panel]: They hypothesize that it may be due to a supermassive object beyond the edge of the visible universe.
:Cueball: Maybe it's your mom. Zing!

:[Only Beret Guy.]
:Beret Guy: Do you think?

:[Outside at night, on a rooftop. Beret Guy is looking up to the sky, next to a telescope.]
:Beret Guy: Pull harder, mom.
:Beret Guy: I Miss you.

==Trivia==
* Beret Guy's "A.S.T. paper" might refer to the [https://iopscience.iop.org/article/10.1086/592947 article] that first mentioned the theory of {{w|Dark flow|dark flow}}, published shortly before this comic. The article appeared in the {{w|American Astronomical Society}}'s {{w|The Astrophysical Journal|Astrophysical Journal Letters}} (ApJL), but it is unclear what is meant by "A.S.T." in the comic.

{{comic discussion}}

[[Category:Comics with inverted brightness]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Beret Guy]]
[[Category:Astronomy]]
[[Category:Space]]
[[Category:Your Mom]]
[[Category:Space probes]]
[[Category:Telescopes]]

475: Further Boomerang Difficulties

2026-02-17T11:38:09Z

2A00:23C8:3309:F01:250F:FA3F:D0CE:BFBF: /* Explanation */ Moving [citation needed] to better spot

{{comic
| number = 475
| date = September 12, 2008
| title = Further Boomerang Difficulties
| image = further_boomerang_difficulties.png
| titletext = An eternity later, the universe having turned out to have positive curvature and lots of mass, the boomerang hits him in the back of the head.
}}

==Explanation==
This comic is a sequel of sorts to [[445: I Am Not Good with Boomerangs]], as it deals with the same subject matter with the same panel layout.

The first strip shows [[Cueball]] throwing a boomerang, which doesn't come back. He looks downwards in the rightmost panel as if in shame. In [[939: Arrow]], a boomerang returns to Cueball, which can either be the same Cueball from this comic or another person.

In the second strip, he throws another boomerang, which somehow manages to hurt the {{w|ozone layer}} (as indicated by an off-screen voice). This is of course not possible with a boomerang{{citation needed}}, as the ozone layer is a layer of O<sub><small>3</small></sub> molecules very high up in the atmosphere.

The third strip shows Cueball throwing something that ''appears'' to be a boomerang, but then [[Megan]] enters and reveals that it was their last banana - which she probably had expected to eat since she calls him an asshole. Perhaps this is why she broke up with him in the first comic.

The final strip shows Cueball throwing one last boomerang, which breaks the frame of the comic, already after two out of the four frames used in each of the first three strips. In the second panel, Cueball seems to be leaning backward in shock or terror. Then, panning down, we find the last panel, much larger and suddenly mainly black instead of white. It shows that this time he was actually inside a spacecraft (which resembles an {{w|Apollo Lunar Module}} in a very bad manner), and the boomerang has just broken out through the hull. We see the boomerang and Cueball tumbling out into space with the escaping air to certain death, revealing why Cueball was so taken aback when the boomerang broke through the frame.

If you try to link up the rightmost panels, as what was suggested [[445: I Am Not Good with Boomerangs]] to get a bonus comic strip, you get a bad story where Cueball is looking down, presumably in shame. Then a person (presumably Megan), screams about the ozone layer. We also see Megan call Cueball an asshole, probably because he had destroyed (or messed with) the ozone layer.

The title text notes that, assuming a theory that is {{w|Accelerating universe|no longer generally accepted}} where the universe has a positive (closed) {{w|curvature}} and lots of mass, the boomerang would, after a (very) long time, hit Cueball in the back of his head. This would happen because under those conditions the entire universe would eventually fall back on itself in the {{w|Big Crunch}}. Before this happens, everything would again get pressed close together, and it is during this process that the boomerang would finally return to his frozen (but quite possibly preserved) head. (So at least one "success" in four attempts.)

Boomerangs also became a main theme in the interactive comic [[1350: Lorenz]]. The same format of multiple bad endings to the same starting set-up is used in [[1515: Basketball Earth]].

==Transcript==
:[Cueball is throwing a boomerang.]
:[Holding his hands up.]
:[Cueball waits for return; continual waiting.]
:[Cueball is dejected, head hangs low.]

:[Cueball throws a boomerang.]
:[Cueball waits for the boomerang.]
:Outside: Oh God
:Outside: The ozone layer!
:[Cueball is surprised.]

:[Cueball throws a boomerang-like banana.]
:[Cueball waits.]
:[Megan walks in.]
:Megan: That was our last banana.
:Megan: You're such an asshole.

:[Cueball throws a boomerang.]
:[The boomerang breaks out of the panel box.]

:[The boomerang breaks out of a spacecraft, followed by Cueball.]

==Trivia==
*Part of this comic and [[939: Arrow]] is the picture for the {{tvtropes|BrickJoke|Brick Joke}} page on TV Tropes.

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Boomerangs]]
[[Category:Physics]]
[[Category:Food]]
[[Category:Space]]

explain xkcd - User contributions [en]

502: Dark Flow

475: Further Boomerang Difficulties