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I think the main lesson would be that making your transistors and switching currents enormously large is good for longevity in space, but that's nothing new.

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Well, I was also thinking about (but didn't write) that most mission-critical systems aren't written in javascript :) ... but rather something "ancient" like ada or pascal.

I kinda doubt that any satellite from this era ran a high level language.

Why? The first high level languages were already existing in 1942, so it’s not that far fetched.

EDIT: As I can’t answer to comments due to the retarded "you are submitting too fast" rule, here is a source: https://en.wikipedia.org/wiki/Plankalk%C3%BCl

.. on room-sized computers. VLSI hadn't been achieved yet, so Apollo flew with a suitcase-sized computer made from discrete gates and core memory programmed in assembler by Margaret Hamilton and others. https://github.com/chrislgarry/Apollo-11

I doubt the satellite bothered with a processor.

Not trying to be pedantic or a dick, but you should refer to that language as assembly, not assembler. It is a non trivial difference as assembly refers to the language and assembler refers to the software written to parse assembly commands into machine code (binary strings defined in the given machine's instruction set that are meaningful to the processor).

Otherwise it's similar to referring to the language C as Compiler, which is just silly :)

http://stackoverflow.com/questions/1176138/assembly-vs-assem...

Also, to your point, agreed. It took several years before we could actually fly high level, compiled languages in space, the first being HAL/S on the Shuttle (completed in 1975).

https://www.cs.toronto.edu/XPL/hal.html

Cheers

This is the most pedantic thing I have seen in 2016.

I dunno how other !English languages handle it, but in German both are simply called Assembler. It would also seem that this distinction isn't generally made, due to the human ability to deduce meaning from context.

You must be new to HN.

I'm gonna need a source on that.

The first actual formalised and widely used programming language was FORTRAN in the 50's.

Which just had its 60th birthday a couple weeks ago.

From the article you linked:

> the first compiler for it was implemented in 1975

Although a few high-level languages existed at the time, compilers back then were not capable of code optimization. The only way to write code tight enough to operate a spacecraft would have been Assembly language.

Nonsense. Fortran I (happy 60th birthday!) was an optimizing compiler, and would have failed had it not been.

Who knows, IIRC planes are dedicated C++ frameworks that spit out tons of intermediate representations and then compiled.

Not a satellite, but Deep Space 1 ran on "Remote Agent", which was entirely written in Lisp and even had a remote REPL, which was used to debug and fix a race condition bug while millions of miles away.

That and more about Lisp at JPL are on this awesome little page written by a former JPL engineer: http://www.flownet.com/gat/jpl-lisp.html

While fascinating and true, DS1 was launched in the late nineties, over forty years later. Pretty sure that's a different era :)

Oh, did I misunderstand what he meant by "this era"?

I would assume the proper way to phrase it would be "that era" if he meant the 60's, although he did use "ran" which is the past tense. He also mentioned JavaScript, which didn't even exist in that era, so I guess I'm confused by the entire statement.

Edit: by 'he' I guess I meant 'you'. Which means you did mean to refer to the 60's.

"This era" here means the era in the context of the discussion, not the current era. "That era" would also be correct.

That's incorrect. Commercial avionics are written in C++ these days. Automotive systems are in C or C++. Ada never got any real use outside the US military, and even there it's dead.

Not if you read something like this:

https://www.seas.gwu.edu/~mfeldman/ada-project-summary.html

Sure, the "military" list is the longest, but far from the only one. I also notice four Swedish military systems there (yay :) )

Ada ain't dead. It's still in use for some aircraft systems, not all of which are military.

It's probably all legacy stuff. The avionics stuff I worked on was all C++. I got to see some Ada code, but it was all ancient legacy systems that hadn't been replaced yet. I seriously doubt anyone is starting any new projects in it.

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