786: Exoplanets

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Exoplanets
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!

[edit] Explanation

Beret Guy runs to wake up Cueball 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. As Beret suggests, Project Orion was an early project to come up with 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 massive degree of 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, even now.

Beret Guy references Stargate Atlantis when he mentions "City-Ships" as the city-ship Atlantis was the basis for the show. The city-ships on Stargate Atlantis are about the size of Manhattan.

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 and be left behind!

Cueball would just rather snooze, as he is not impressed. 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.

[edit] Transcript

[Beret Guy runs into the room, someone is in bed under the covers.]
Beret guy: Wake up! Wake up!
Cueball: What is it?
[Beret Guy stands talking to Cueball still hiding under covers.]
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!
[Dramatic shot of just Beret Guy.]
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 to eye level with Cueball in bed, who is peaking his face out from the covers.]
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! Come on!
Cueball: Can I hit "snooze"?
Beret Guy: Okay, but just once!
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Discussion

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. 99.111.149.90 (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. ‎152.93.147.10 (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]--173.245.54.11 04:53, 11 May 2014 (UTC)
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