# Talk:Space Travel (video game)

I wrote to Ken Thompson asking if Space Travel was ever ported to a modern environment or if there were images of it available anywhere. His response was "sorry, it is completely lost."
I recognize that Wikipedia doesn't allow emails to be a reference for statements in an article so I'm including this information here for history's sake.DasKreestof (talk) 14:54, 19 October 2011 (UTC)

This review is transcluded from Talk:Space Travel (video game)/GA1. The edit link for this section can be used to add comments to the review.
Reviewer: J Milburn (talk · contribs) 20:27, 13 March 2016 (UTC)

Happy to offer a review. What an interesting topic. Josh Milburn (talk) 20:27, 13 March 2016 (UTC)

I'm struggling to understand the Phobos example. Should it perhaps read "the player must allow the ship to fall below the surface, after which it suddenly snaps back to be landed"? I think that makes more sense, though I confess I'm still not quite sure what is being claimed.
Reworded the bit, hopefully it makes sense now. The idea is (making up numbers), that when you're at 0 feet above Phobos, Mars is still the stronger gravitational pull, so you can't "land" on the surface, so you can keep going down. At 100 feet below the surface, though, you're close enough to the core of Phobos that it switches to be the strongest pull, but at that point you're "at or below 0 feet above the surface of the body with the strongest pull", so the game snaps the ship up to the surface as "landed".
"popular variations by the original players were to adjust the coordinate system so that it rotated around the nearest gravitational body" I don't understand
Reworded/expanded, does it make sense now? I can picture it in my head, but it's hard to put in words.
"run on an "interactive batch" model where several terminals were attached and each program job had to be submitted in a queue" I'm not sure "where" is the correct word here. Do you perhaps mean something "run on an "interactive batch" model, meaning that several terminals were attached and each program job had to be submitted in a queue"? Also, what's a "terminal"?
Yes, I was just misusing "where". And now renamed/linked to computer terminal; I've been so buried in 1960s computing technology that I forgot most people have no idea what terminals are, since they vanished pretty fast once microcomputers popped up in the 70s. A terminal is just a screen/input device, and you could have multiple terminals hooked up to one mainframe computer. The computer used basic multithreading to run the jobs for terminal 1, then terminal 2, 3, etc- it didn't have complicated interleaving of instructions like a modern multi-core processor, so trying to play an interactive game could be a pain since at any time you could have a pause as the computer was busy doing jobs for other terminals- it was designed for things that didn't need real-time response. The idea was that you could have multiple people working at once on different terminals, since realistically they weren't all going to be doing heavy processing work all at the same time, and computers were stupid-expensive so reusing the interstitial downtime of an existing one was much cheaper than buying another computer.
"managed to find out that a neighboring department" Why not simply "learned that a"?
Fixed
"Thompson, however, managed to find out that a neighboring department had an older PDP-7 minicomputer that was little-used, which he could re-purpose." This doesn't quite work. Perhaps you could split the "which he could re-purpose" bit off into a sentence of its own?
Pulled the "that was little-used" phrase back into just an adjective instead
"As a result, he implemented his own floating point arithmetic package, graphics coordinate system for outputting to the screen, and a debugging subsystem to display what was at a location if the user typed one in" I'm a long way from a computer scientist, but neither am I tech-illiterate. I'm struggling with this.
Yeah, that got a little jargony. I'm a programmer, so it was all just English to me. Fixed.
What are "paper tapes"?
Renamed/slightly expanded/linked to punched tapes. He wrote the programs in "human-readable" assembly code, and the GECOS computer assembled that code into machine-readable code and then punched holes representing the result onto strips of paper. The paper strips were then fed into the PDP-7. This was a pain, obviously, so he wrote an assembler for the PDP-7 so that he could just write the assembly code there in the first place. Computer science in the 60s was a very different place than today...
I'm not going to pick on reference formatting for the purposes of GAC, but I note that you should probably cite the author of the encyclopedia entry if different from the encyclopedia's editor. So (I can't see your Google Books link...) it'd be something like: Smith, John (2010). "Heavy Stuff". In: Jones, Henry, ed., Encyclopedia of Stuff. Oxford: Oxford University Press. Sources all look appropriate, though.
I was going to say that I'd like to, but the snipped I can see is just those two pages and the author isn't listed, but it looks like the index is also visible to me so...added.
Category:Space flight simulator games? Category:Unix history? Category:Bell Labs (or a subcategory)? (I'm surprised that we don't have a video games category in Category:Unreleased works by medium, but I'm not going to ask you to add one...)
Added all. Yeah, video games has their stuff in Category:Cancelled video games and Category:Upcoming video games, but doesn't have anything for "done but not published". I wouldn't put this in it anyways- it was made for the one machine with a custom operating system, played only by the people it was made for, and never intended to be played by anyone who didn't play it. There was also no commercial video game industry until the early 70s, so there wasn't really a way to "release" it anyways.
Plenty of hits on Google Scholar, but you seem to have gotten the important stuff down. I wonder if you have easy access to the book A Quarter Century of Unix? Looks like there may be something good there, but don't lose sleep over it!)
Yeah, almost all the sources are just based off of Ritchie's comments about the game, which are used directly here. I don't have access to A Quarter Century of Unix, which is a shame, since it does look like it might have something. I'll keep an eye out for it.
What am I looking at in the lead image?
I...wish I knew. Really. It's the only image of the game I can find, and there's no explanation given for it. Pretty sure it's the ship, since that's supposed to be at the center of the screen at all times facing the top, but that's all I got.
Again, a really interesting topic. A great little article- I'm just being picky above, really. The one thing I'd say is that the writing is sometimes a bit tech-jargon-heavy. Josh Milburn (talk) 20:59, 13 March 2016 (UTC)

@J Milburn: Replied inline. Sorry about the jargon; I've been mired in writing, well, actually all of the articles we have on 1950s/60s video games the last couple of months, and sometimes I forget what things are utterly foreign to people now, even computer-savvy people. --PresN 15:57, 14 March 2016 (UTC)
I'm happy to promote at this time. I don't think the prose is perfect ("The player is able to control the ship to go forwards and backwards and turn" is a little clumsy, and the development section is probably still a little jargon-heavy, for example) but I'm happy that it's strong enough for GA purposes. Nice work- an interesting little topic. I confess I didn't realise that things like this were being made as far back as the sixties. Josh Milburn (talk) 16:57, 17 March 2016 (UTC)

@J Milburn: Thanks! Yeah, see Early history of video games (GA, also by me) if you're interested in more about 50s/60s video game history- there was a sudden, sharp jump from tic-tac-toe and the like to rather involved games like this and Spacewar in the 60s. --PresN 17:58, 17 March 2016 (UTC)

Can someone explain what the gameplay image represents? According to the body text, the ship remains at the center and the solar system rotates around it.
Well I don't see a ship... possibly this is represented by the screen-spanning crosshairs? If so, that needs to be mentioned.
And what exactly is that figure-8 object just above center? Is that supposed to be a planet or moon? Again, I can't square that image with anything in the description.
Maury Markowitz (talk) 19:13, 5 July 2018 (UTC)

Source code for the PDP-7 Unix version of Space Travel has recently been recovered, along with a good amount of other code of other PDP-7 Unix applications. There's a project on GitHub that has managed to get PDP-7 Unix up and running under the SimH emulator, and the source for Space Travel is now in the source tree. GitHub project
Unfortunately it also requires someone to also write an emulator for the custom GRAPHICS-2 terminal that this specific PDP-7 used. Work on that is progressing too, but at the current moment in time the code hasn't yet been committed to the SimH Github Project. SimH GitHub project Paul The Wazzock (talk) 15:21, 13 November 2019 (UTC)

Very cool! Hopefully once that gets finished, we can get a screenshot that's actually understandable. If there's a good link target once it's working, that can be added as an external link as well. --PresN 19:20, 14 November 2019 (UTC)
There's a video of a guy who got Space Travel running on an experimental branch of that PDP-7 Unix. Might be a good source for a better screenshot of the game. JKeck (talk) 20:49, 25 January 2024 (UTC)