786: Exoplanets

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I'm just worried that we'll all leave and you won't get to come along!
Title text: I'm just worried that we'll all leave and you won't get to come along!


Beret Guy runs to wake up Cueball, who is probably under the covers in bed, with his potentially middle of the night revelation that Humankind is discovering "exoplanets" or planets that exist outside of our solar system. The indication is that these planets are habitable enough for humans, even if just for a visit.

Then Beret Guy takes it a bit further thinking that one of the countries on Earth could restart Project Orion (which is later mentioned in 2423: Project Orion. As Beret suggests, Project Orion was an early project to produce a spacecraft that would ride the shockwave from a series of nuclear bombs it dropped in order to travel very, very fast. However, the one major downside of Project Orion was the fallout that the launching of any such craft would present on Earth. One could try to boost the Orion spacecraft into orbit with conventional rockets, but Orion spacecraft are heavy — being composed of giant pusher plates and rows upon rows of nuclear bombs, they are hard to lift. On top of this, the Nuclear Test Ban Treaty means that the craft would be flatly illegal to build and launch on Earth, no matter what you did. However, if an asteroid mining project were to be started, the Orion drive spacecraft, the nuclear bombs, and all the infrastructure needed to man, build, and crew it could all be built safely in space, well away from the Earth's fragile biosphere, where little harm could be done. Some commercial spaceflight programs are interested in starting asteroid mining in the future, or even now: For example, see: https://www.planetaryresources.com.

In summary, Beret is very excited that we can see (with the Hubble telescope and other earth-bound telescopes) and find exoplanets. Then with some advances in space technology we can create nuclear propulsion in space to reach these planets, and it will all be happening quite possibly within a few decades. He is thus worried that Cueball will miss all of this ongoing excitement.

Cueball would just rather snooze, as he is not impressed. Beret Guy gives him only one snooze because as is apparent in the title text he is afraid that Cueball will be left behind if he snoozes too long! Giving the fact that he just stated that it may take hundreds of years this is of course silly but fits well with Beret Guy's behavior.

Exoplanets have been discovered starting in 1996, but there are still only a few confirmed planet candidates in the habitable zone at a distant star. This did change fast after that time since new ways of finding planets are created — see 1071: Exoplanets, which was posted with the same title. At that point, there were exactly 786 Exoplanets confirmed — the number of this comic - probably not a coincidence when it comes to Randall.

Part of the humor of this particular strip is that Beret Guy seems to have a sense of urgency and immediacy about something that is actually occurring at a snail's pace over decades, where Cueball finishing sleeping, or hitting snooze twice, couldn't possibly make one crystalline erg of difference.

1624: 2016 is similar to this comic in that in each case, one character wakes up another character in order to inform that character about an event that is neither immediately relevant to that character nor short/urgent enough that that character could miss it if he slept until the morning.


[Beret Guy runs into a bedroom arms up calling to someone who is in the bed under the covers. Only part of the bed is visible. The person under the covers speaks. Later part of his face can be seen, and it could be Cueball.]
Beret guy: Wake up! Wake up!
Cueball (under the cover): What is it?
[Beret Guy stands with his arms out talking to Cueball hiding under the covers of the bed now completely inside the panel.]
Beret guy: We're alive during the time when they're first discovering other planetary systems! They're finding them as fast as they can build new instruments to look for them!
[In this frame-less panel only Beret Guy is shown standing with one arm out and one arm up looking left away from the off-panel bed.]
Beret Guy: And if one of Earth's cultures advances its space program enough to start enriching uranium on asteroids, we'll lose the main barrier to restarting Project Orion and building nuke-riding city-ships!
[Beret Guy bends down, hands on his knees, to eye level with Cueball in the bed, who is finally peeking out from the covers, only showing part of his face (so it could be any character, as any hair could be hidden, and the hat could be on the bed stand).]
Beret Guy: The only known technology capable of fast interstellar travel could be operational within just a few generations, and we're discovering all these destinations to pick from!
Beret Guy: Come on!
Cueball: Can I hit "snooze"?
Beret Guy: Okay, but just once!


  • This was the first time Randall released a comic with the exact same name as a previous comic, in this case 1071: Exoplanets, released on June 20, 2012. Since then, he has done so a few times. When the new comic was released, it caused problems on xkcd as the title of the image file (explanets.png) was the same for the two comics. This was resolved by renaming this comic's image, adding the year of its release to the title: explanets_2010.png.
  • The number of this comic (786: Exoplanets) is the same number of planets featured in the comic 1071: Exoplanets (786 planets) with the same title. It isn't clear whether this is a coincidence or Randall purposefully waited for the number of discovered planets to be the same as this comic's number.
  • Cueball is not completely visible in this comic, and the last image only shows a face. Given that almost all characters without a beard have the same face, this could be any character, including one with a hat (which could be hidden or outside of the frames) or hair (several of the usual styles). The comic's official transcript refers to this person as "bed man", meaning it isn't intended to be a female character. As it is easier to explain the comic using Cueball's name, and given that he is the usual guy to draw when no particular features are added, it still makes sense to call him Cueball in this comic.

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There is no indication that SG:A is the city-ship being referenced. Atlantis does not fly by Orion-drive and is in no way the first Sci-fi reference to City ships. They go back at least as far as "Cities in Flight" by James Blish and possibly further, although I've found no evidence of this. -- (talk) 12:04, 19 January 2013‎ (UTC) (please sign your comments with ~~~~)

Also note that this comic is no. 786, which is the amount of known exoplanets. -- ‎ (talk) 09:17, 21 February 2013‎ (UTC) (please sign your comments with ~~~~)

But this was released 2 years earlier than that count; still it's interesting factiod... Mark Hurd (talk) 11:07, 13 April 2013 (UTC)

Footfall by Larry Niven is the best example of city-ships in line with Project Orion. Basically the bigger they are the better. Big metal plate with a city on top and nuclear bombs exploding underneath. And the project started in the 50s. [1]-- 04:53, 11 May 2014 (UTC)

Before restarting Orion, why not start with a more modest goal: a facility to assemble spacecraft on the moon from parts made on Earth? Even without the mining, it'll mean we can launch a craft from Earth in several smaller rockets instead of one big one. Promethean (talk) 01:30, 14 February 2018 (UTC)

Look at you, predicting the Artemis Program... 03:00, 11 February 2021 (UTC)
Not to have a conversation with three-year pauses, but why not assemble the ship in orbit? That way you don't have to use up large amounts of propellant to land ships in the moon's gravity well, then boost the completed vessel away again. Nitpicking (talk) 01:19, 5 September 2021 (UTC)
We don't have the infrastructure yet to build things in space, the US is working on it but these things take time, and planning--Lackadaisical (talk) 19:12, 6 September 2021 (UTC)
We don't exactly have the infrastructure to build things on the moon, either, you know. It would still be easier in space. Nitpicking (talk) 01:03, 7 September 2021 (UTC)
Not exactly, it costs money to send materials into space, materials we have to launch from the earth's gravity well, if we could instead use resources on the moon we can then use those resources to build things on the moon and launch them into space from the moon's gravity for less than we could launch those same materials from Earth. Eventually we can transport asteroids to orbit earth for raw materials in orbital factories and we won't have to worry about launching any of those --Lackadaisical (talk) 19:43, 29 September 2021 (UTC)