1458: Small Moon

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Small Moon
GENERAL JAN DODONNA: An analysis of the plans provided by Princess Leia has reinvigorated the arguments of the 'artificial moonlet' and 'rogue planet-station' camps. I fear this question is fracturing the Rebellion.
Title text: GENERAL JAN DODONNA: An analysis of the plans provided by Princess Leia has reinvigorated the arguments of the 'artificial moonlet' and 'rogue planet-station' camps. I fear this question is fracturing the Rebellion.


The comic depicts a classic scene from Star Wars Episode IV, in which the heroes trail a TIE fighter to the never-before-seen Death Star: a super-weapon the size of a small moon capable of demolishing entire planets. In the original scene and the comic, Luke Skywalker misidentifies a body as a natural satellite, and Obi-Wan 'Ben' Kenobi ominously corrects him.

The comic's version diverges at this point, as the dialogue devolves into a rather bitter argument over the semantics of size classifications, alluding to scientific discussions on whether Pluto should be classified as a planet or as a dwarf planet. The argument goes on for hours, which in the original plot would suggest one of two situations:

  • The Death Star apparently never caught them, and Princess Leia was never rescued (but Ben survived); this take is supported by the official transcript.
  • The argument was picked up after escaping the Death Star, and now Leia is joining in.

The argument is confused as to whether they're talking about size or about natural vs artificial objects. In terms of size, the Death Star is much larger (70 km radius) than dozens of full-fledged moons in our solar system. One of the smallest moons found so far in the solar system is S/2009 S 1, which is about 400 meters in diameter and orbits Saturn. But we don't generally speak of the tiny rocks in the rings of Saturn as moons, so there is some distinction there, which may include the orbit of the object [1]. There is also the distinction between natural moons and spacecraft, which seems to be ignored in the final panel.

The title text makes reference to a later scene in the film when Rebel pilots are being briefed on the planned attack on the Death Star. Those who analysed the plans for the Death Star run into the same discussion picture, and end up arguing about the classification of the Death Star, dividing those involved into the "artificial moonlet" camp and the "rogue planet-station" camp, thus deunifying the rebellion. If events are otherwise the same from the movie, this is also happening at threat of their destruction, and thus a crippling of the Rebellion.

The timing of the comic may be related to the New Horizons mission to Pluto. The spacecraft awoke from hibernation 4 days earlier, on December 6, 2014, to start the encounter phase with Pluto.


[Millennium Falcon follows a Tie Fighter towards an unidentified orb in the distance.]
Luke Skywalker: He's heading for that small moon.
Ben Kenobi: That's no moon - it's a space station.
Luke Skywalker: It's too big to be a space station.
Ben Kenobi: But it's too small to be a moon.
[Three hours pass]
Ben Kenobi: Fine! What if we agree it's not a moon, but we make a new category called "Dwarf Moon"?
Luke Skywalker: And what's the cutoff, asshole?! Is this ship a dwarf moon now?
Ben Kenobi: Screw you.

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Probably another dig at the Pluto "dwarf planet" controversy? 06:38, 10 December 2014 (UTC)

Implying that it might not be? 15:54, 10 December 2014 (UTC)

This is too good. I laughed for about 2 straight minutes.. :D 06:50, 10 December 2014 (UTC)

Added a short placeholder explanation for the comic itself, using's suggestion. Needs refining and explaining of the alt text. Cheers. 07:04, 10 December 2014 (UTC)

In the movie, they didn't have 3 hours to argue over the thing. Not sure if that's relevant... Haelbarde (talk) 07:11, 10 December 2014 (UTC)

The reason it couldn't be a space station would be that something so large would wind up collapsing in on its own gravity. 08:38, 10 December 2014 (UTC)

It's not solid, it's a comapritively low density on the whole (on the order of ten thousand millionths that of Earth's sea-level atmospheric pressure, if I've not thrown a rogue zero or two in to the calculation by accident, so is doubtless mostly vacuum outside of the functional/habitable/structural areas), there are obviously various gravitational compensators for the inhabited sections (hence "looking sideways out of the equator ring" and along the beam-channel, yet "up from the surface" from the trench system defence turrets and other internal shafts are also vertiginously 'up-down' in nature) and doubtless its structural stength is composed of various Unotanium (i.e. "durasteel") alloys and the like, way beyond what we could currently build with Earthly technology. 10:37, 10 December 2014 (UTC)

I would note that a Death Star can not be a moon. Briff (talk) 10:10, 10 December 2014 (UTC)

Note that it is canon that the "Star Destroyer"s are neither (if taken literally) capable of destroying stars nor (in the sense of "star ship" in general) are they technically destroyer-class ships. You've got to put it down to The Empire just having no sense of relevence when it comes to naming its vessels. Probably too much influence from clone-thinking... 10:37, 10 December 2014 (UTC)
I will argue that by my understanding of the term, it actually is a moon whenever it is orbiting a planet but it would probably be better to come up with new terminology given the interstellar capabilities. -- 12:44, 10 December 2014 (UTC)Band of Traveling Accountants

I've never heard of the word "deunifying"; did you mean "disuniting" or "disunifying"? 14:09, 10 December 2014 (UTC)

That would probably have been me who wrote that. I didn't spend too much time thinking about it, was just putting something up, fully expecting it to get fixed up later Haelbarde (talk) 00:57, 11 December 2014 (UTC)

I marked the transcript as incomplete; we can't be sure as to who is saying which lines in the final panel without Randall telling us himself. Notably, the second-to-last-line does not sound like something Ben Kenobi would say; more likely it's Han Solo. 13:54, 10 December 2014 (UTC)

Agreed. Comment is much more easily seen as coming from Solo than Kenobi. And, if they did rescue Leia during the intervening interval (one of the two scenarios suggested), Kenobi wouldn't be present. Equinox 16:59, 10 December 2014 (UTC)
I have two reasons why I'd stick with my original Luke and Ben for the last panel: 1) On a cursory read of the comic, without thinking about what would have happened in the movie, the natural assumption is they have been arguing for the entire 3 hours, so its the same two people, and 2) If they had actually been captured by the Death Star, there would no longer be any argument. They would have found upon closer inspection that it is in fact a space station. Note that in the final panel they're arguing about classifying it as a moon, as opposed to the Title Text, in which the options both acknowledge its artificial/station status.Haelbarde (talk) 00:57, 11 December 2014 (UTC)
Randall's official transcript (in the source code of http://xkcd.com/1458/, look for <div id="transcript" style="display: none">) shows who is saying what in the last panel. Therefore, I have updated the previously "Unknown" speakers in the Transcript section for this comic. 23:32, 3 August 2015 (UTC)

Dear other editors: "In this galaxy" was wordplay on the Star Wars opening crawl. I find your lack of pop culture disturbing. Changing the phrase to "In this solar system" was incorrect. Furthermore, although the predominant civilization on Earth allows moons of nearly any size, it is not necessarily true that inhabitants of SWG followed the same nomenclature. I think the wording should be restored. - Frankie (talk) 17:42, 10 December 2014 (UTC)

In fact, we know for sure that SWG defines "moon" differently than we do, because when the Millennium Falcon arrived, the Death Star was not orbiting another non-star body (it was the largest body in its spatial neighborhood) and therefore could not be a moon (as defined in this galaxy). - Frankie (talk) 18:03, 10 December 2014 (UTC)
Frankie's observation is something I thought of after seeing the movie as a kid, but the station could actually be orbiting the combined gravity of the debri field of the planet it just destroyed. The 'tidal' forces on the station would be different from the debri than from the planet, because the matter is now distributed differently, but the death star still could be an orbiting body, for a while at least. Once the debri field becomes more distributed the situation would be as Frankie stated. SeanLynch (talk) 15:54, 11 December 2014 (UTC)

I notice Randall removed the "We'll be back next week" line from his What-If page today. I wonder what's up since it's been over two weeks. 02:21, 12 December 2014 (UTC)

Would it be fair to say this strip is also a reference to the fact that any object of large enough mass in space would have its own gravity? (Setting aside an earlier comment about the Death Star being mostly vacuum) (talk) (please sign your comments with ~~~~)

I haven't seen Star Wars in a while, but was it not Han Solo who said the "It's too big to be a space station" line? After all, Solo was more worldly than Luke at the time. Phineas81707 (talk) 08:59, 4 May 2016 (UTC)

Actually, in Munroe's transcript it says 'Luke: It's too big to be a space station.' Should we stick with the transcript on site or with the canon (according to which you are correct, Phineas81707)? After all, the comic is diverging anyway and does so just two lines earlier, according to Munroe's transcript. (talk) (please sign your comments with ~~~~)
Please don't forget to sign your comments. But thanks for your eagle eyes, at the original transcript it's Luke. I'll fix it. --Dgbrt (talk) 22:14, 5 November 2018 (UTC)

Just fixed some vandalism, some guy filled the entire page with just the word crap. Smell ya later. 01:01, 4 May 2022 (UTC)