Why does NASA use linux instead of Windows ?

[GarryRicketson]

the end of XP meant a cash cost of around $7000 to move to Win7

Wow, I find it hard to believe any one would pay that much, for Mal-ware that does not work well, based on the current exchange rate : that is in mx pesos, 105,000.00 mx
And for something that does not work well,..???
I made a small donation, as much as I can afford to Debian, and I am sure a government organization like NASA, does make some large contributions, I don't use Debian, because I want a "free meal" I use it because of the quality, even if it was a commercial OS, and it cost some thing, I would buy it. But I would never even use Windows,none of the versions, even if they were free as in "free lunch", so any way, I am not convinced that NASA uses linux, just because it is "free", but of course the economic factor, is a important factor, combined with the cost of the OS, then the additional expenses due to down time, when the mal-ware fails, additional software needed to support it, keep it secure , etc. that does make windows, a non-solution, or not a option, even more so for a business, where a economics are crucial .
I know what you mean though, here, where I used to work, I was just a "stone cutter", crafts man, ...but also the computer, etc, is a hobby I am not any kind of "high tech" engineer, or pro,..Any way, to make a long story short,.. when my boss realized I enjoy doing things with computers, he bought me a small acer laptop, at that time it had been close to 5 years, that did not even have my own computer,..so anyway, the laptop came with windows XP, on it, I was happy, but as soon as I realized how useless the windows XP is, the same or even worse then the earlier versions, well, I got online, and downloaded "free dos", and "bye bye windows",..put the "freedos" completely overwriting the "mal ware", Then I also downloaded, a linux live CD, (knoppix), installed that as well, later , Xubuntu,...(this was 10 years ago), Any way, at the same time, it was costing the company , where I worked, 10 to 15000 pesos a month, or 120,000 pesos a year, to have a tech come and update the ant-viruses, etc,..everything he needed to keep the windows mal ware working, ... When I showed my boss about linux, and had my laptop connected to the modem,.. demonstrating it,... well, he liked it, but problem, there are not very many techs, in this area, that know anything about linux, But any way, I installed the new system, and now, it is very rare indeed that I am needed to do anything with that, it is a reliable , minimal maintenance system, not to long ago I updated it to newer versions, ...still Xubuntu,.. now I have been using Debian, 10 months now, and am confident, that he will be comfortable with it, if and when he wants to install a new system , that will be what I recommend,.. any way, to long of a story, and still a lot of "details" not included.... if a "non tech" type person like me, can install and maintain the OS, that is really a "user friendly" OS, ... the windows, junk,..I never could even come close to figuring out, I guess all that "high tech" stuff is above my head, ...I mean after all , I do sort of live, or used to live "under a rock",.(now retired, and live at home) ..that is all I did all day, cutting them up into smaller rocks, and making things with them, but that is another topic.
The point being, if a guy, that never went past the 5th grade, like me, can work with linux, then imagine how much easier it is for the "rocket scientists"

[andre@home]

Good points!
Quite some decisions to take in order to make that process run smooth and cost effective.
It also quite dependent upon the type of organization.

In ours (~1700 people world wide) the costs are quite high. The costs are calculated per working place; hardware is only a minor part of it. Machines are often leased and the lease time is only extended nowadays as hardware stays longer ok (leasing because of spread of cost/depreciation balances). As we also have an intranet, sharepoint and quite some other on line database, and in the future an on line electronic notebook, this adds to the cot of a working place considerably.

Teaching people to work with Linux is one point, but as we are in a technical area with quit some modeling, either self-programmed in C++ like stuff but also quite a lot using excel with quite advanced macros, a huge amount of application need adaption or even completely rewritten (programs but also macros). Although I'm in favor for a switch to Linux... I see also such kinds of work, so costs indeed as a significant hurdle to make that switch.

So.. good points indeed you've indicated!

[GarryRicketson]

I do realize, especially in offices and networks , where all or most of the employees only know how to use windows, and the software that is for windows, it is not something that can easily be done "overnight" to make a change over to another OS, and even though many of the software for linux is very similar, to what MS has, there is a "learning curve", and probably a expense involved in training them, some time lost, while they get familiar with the new programs, etc,...
I struggle here, with a teacher, that insists on the kids using windows xp, but after all said and done, when my kid turns in his home work, the dumb ass teacher has no clue he used "libre office", on a Debian system.

[NFT5]

Wow, I find it hard to believe any one would pay that much, for Mal-ware that does not work well, based on the current exchange rate : that is in mx pesos, 105,000.00 mx
And for something that does not work well,..???

$7000AUD, so only 84,000MXN.

No, I didn't. We'd been hit with a few viruses and malware over the years so I was looking for something that was more resistant and I had been playing with a Linux dual boot for some time prior.

I guess that the "free lunch" that you mention was a part of my decision, of course, but, like you I also made some donations to Debian once the changeover was made. It's not that I object to paying for software, per se, but that I see the exorbitant costs of the MS products as unreasonable. We're not big enough to qualify for discounted pricing so OS plus an Office package was going to cost close to $1000 per machine and that I saw as ridiculous.

I think that one should acknowledge that XP, post SP3 was, in fact, reasonably stable and its interface was well known and accepted by users. Its failings were the security loopholes that flowed from its basic structure and needed almost daily updates from MS to stay on top of. It was a bit slow on some of the older machines, so the better performance that came from a switch to Debian, plus being able to keep those machines in service, was also a factor.

Teaching people to work with Linux is one point, but as we are in a technical area with quit some modeling, either self-programmed in C++ like stuff but also quite a lot using excel with quite advanced macros, a huge amount of application need adaption or even completely rewritten (programs but also macros). Although I'm in favor for a switch to Linux... I see also such kinds of work, so costs indeed as a significant hurdle to make that switch.

We do run a couple of proprietary applications that are available for Windows only. These run in XP VMs that I can lock up, safe from the outside world and with a minimal installation so they actually run quite well.

There are also a number of spreadsheet apps that were developed in Excel. Maybe not quite as advanced as yours but, so far, they all run just fine in Libre Office Calc. Still, I appreciate your point that the time/cost to adapt or rewrite existing programs/applications can be significant. Maybe not a deal breaker for many organisations, but certainly need to be factored in.

[tomazzi]

I think, that one of extremely important factors was still not mentioned in this topic:
Electronics created by humanity so far, is not applicable for usage in space.

The key problem is that our electronics is completely unreliable outside of earth's atmosphere, mainly due to a radiation of many kinds (x-rays, ionizing effects, free neutrons, etc). We don't have a reliable shielding against radiation, especially against heavy particles like neutrons - every material is simply "transparent" for them. So, in a cosmic space a special hardware must be used - You can check out topics about radiation-hardened (rad-hard) chips.

How is this related to linux or open-source software?

A very short answer here can be: because to test and discover problems with hardware, one has to be able to detect what particular portions of code have failed - so obviously, one has to know the sources.

It's easier (and cheaper) to operate, test and diagnose problems with open-source mission-critical software, simply because You know the code (and how it works). It's also easier and cheaper to maintain and control single code base - that is, in the long term.

Regards.

[andre@home]

Recently a mission arrived at its target in space after about 10 years.... So with the know-how of at least 10 years ago.... that technolgy can resist all the incoming radiation/heavy particles at least in such a way that we saw the photos of was taken recently of that target environment... do not know about the technology and the OS that was used... (Windows or Linux?)
So there is at least some experience for such harsh/difficult circumstances.....

[tomazzi]

Recently a mission arrived at its target in space after about 10 years.... So with the know-how of at least 10 years ago.... that technolgy can resist all the incoming radiation/heavy particles at least in such a way that we saw the photos of was taken recently of that target environment... do not know about the technology and the OS that was used... (Windows or Linux?)

A very good point
We are sending relatively old and primitive hardware into space - where the size of particular logic elements guarantees that relatively high level of structural damage won't break their functionality. In other words (an example): 20 years old CPU has far bigger chances to work correctly in the space, because single transistor in it's structure has a PN junction 180nm wide, but if You will use a 28nm CPU, it will die within an hour ... (theoretical example).

This also applies to memory chips and their capacity.

In the effect - only relatively primitive electronics is able to survive in the space (for some time) - and this in turn puts heavy limitations on software used.

Regards.