88
votes
Accepted
What operating system(s) were used in the space shuttle?
I was a NASA contractor working on the same contract, but with 3 different companies, writing GN&C code for the space shuttles from 1989 until 1995. Initially, it was Ford Aerospace, then Loral, ...
- 1,527
83
votes
Accepted
What makes Ada the language of choice for the ISS's safety-critical systems?
This Wikibooks link lists its strong points, some of which are:
An extremely strong, static and safe type system, which allows the programmer to construct powerful abstractions that reflect the ...
- 831
60
votes
What makes Ada the language of choice for the ISS's safety-critical systems?
Timing. Ada was developed in the 1970s and 80s with the intent of replacing the plethora of languages used in the US Department of Defense's realtime systems. NASA (and also organizations from Europe) ...
- 73.2k
58
votes
Accepted
What language is software running on the ISS written in?
Almost all of the safety critical software that runs on the US side of the Space Station is written in Ada. I wrote "almost all" rather than "all" because there are probably some low level device ...
- 73.2k
48
votes
Why wasn't the Mars Climate Orbiter's fatal error caught prior to launch?
NASA formed a board to investigate the loss of the spacecraft and reached some high level conclusions. The board cited a number of contributing factors, which I have filtered to include the ones most ...
- 19.9k
40
votes
Accepted
What was the nature of the known bugs in the Space Shuttle software?
Although the Space Shuttle flight software was of outstanding quality, it's completely incorrect to think that there was only one bug. There were many known bugs in the flight software (FSW). Here are ...
- 178k
40
votes
Accepted
Given small computational resources, how was navigation implemented? (Not samples of old guidance software)
In many of the early probes, up until close to Apollo there were not true computers on space probes. All computing was done on Earth and the onboard electronics was known as a sequencer, for Pioneer ...
- 21.4k
39
votes
Accepted
Reasons behind Soviets Using Prolog Programming Language for Buran Space Shuttle?
According to Wikipedia the use of prolog is just a mistake in the CIA report:
Researchers at Keldysh developed two languages: PROL2 (used for real-time programming of onboard systems) and DIPOL (used ...
- 1,539
34
votes
Does the Voyager team use a wrapper (Fortran(77?) to Python) to transmit current commands?
In 2015, the last original Voyager engineer still on the project, retired. NASA specified that his replacement would have to know FORTRAN.
The software was updated regularly after launch:
The ...
- 126k
31
votes
Accepted
Does anybody work on a "spacecraft linux"?
Updates: Added Astro Digital and Planet Labs at bottom.
There isn't a specific Linux distribution for spacecraft. At least not yet. I have heard of groups that basically took Buildroot to build only ...
- 845
27
votes
Given small computational resources, how was navigation implemented? (Not samples of old guidance software)
(originally answered to "Samples of old guidance software")
The first that comes to mind is the Github repository of the Apollo 11 Guidance Computer (AGC). The repository has both Command Module and ...
- 14.1k
26
votes
Why wasn't the Mars Climate Orbiter's fatal error caught prior to launch?
There were a good number of chances to catch the error after launch, which is what most of the reports on the mission focus on. To look specifically at what testing was done before launch this paper ...
- 7,216
22
votes
Does anybody work on a "spacecraft linux"?
Kubos corporation (disclosure: I work at Kubos) have a cubesat-specific Linux distro and a real-time operating system (RTOS), for cubesats with tighter power and processing budgets, since, as noted by ...
- 361
22
votes
What makes Ada the language of choice for the ISS's safety-critical systems?
I remember taking Computer Science courses in the late 90s. The professor of CS explained to our meager group of CS majors that he was going to teach us C, rather than COBOL or Ada, because it would ...
- 7,780
21
votes
Accepted
How is the software for scientific space missions developed?
No, scientific spacecraft are not developed by scientists on the science team. They may develop their instruments, but not the spacecraft. The spacecraft are developed by professional spacecraft ...
- 58.5k
19
votes
Accepted
What computer programs does ITAR say I can or can not write, or share, or use in the US?
With the exception of model rockets made of paper, wood, or breakable plastic, that are passively stabilized, that have low thrust and low delta V, and that do not have guidance software, launch ...
- 73.2k
17
votes
What makes Ada the language of choice for the ISS's safety-critical systems?
From the website:
AdaCore tools can be used to meet verification objectives including
coding standard compliance, code accuracy (prevention of errors such
as buffer overrun, integer overflow, ...
- 814
15
votes
What is the most popular programming language in space?
I wrote code that flew on 3 spacecraft that went to Mars, one to the Moon, one to a comet and back, and a few Earth-orbiting satellites, the last of which was about 10 yrs ago. All of them used C.
It'...
- 546
15
votes
What language is software running on the ISS written in?
There are a lot of programs involved in running the ISS. The exact details are difficult to discern, a lot of NASA's software is available via this site, with some restrictions, but here is what I can ...
- 121k
15
votes
Does the Voyager team use a wrapper (Fortran(77?) to Python) to transmit current commands?
The Voyager spacecraft are still being patched as of 2023.
The uplink is only 16 bits/second, just enough to send (simple) commands. How these commands are generated is irrelevant to the spacecraft. ...
- 14.1k
15
votes
Given small computational resources, how was navigation implemented? (Not samples of old guidance software)
I am a software developer and with all the resources available today I cannot fathom where one could even start such an endeavour.
There are plenty of computer-based systems to this day that have to ...
- 73.2k
14
votes
Accepted
Besides retarded gravitation, anything else to worry about when calculating MU69's orbit from scratch?
This is not a complete answer. It is instead an extended comment to the following:
I understand I will have to retard the gravity from each source by its particular light-time, as well as correct ...
- 73.2k
12
votes
What operating system(s) were used in the space shuttle?
For the flight control computers, aka General Purpose Computers (GPCs) there is a good writeup on this topic in the ever-useful Shuttle Crew Operations Manual page 2.6-20.
DPS in this quote stands for ...
- 178k
12
votes
Transitioning into space software engineering
Developing software to help with space stuff doesn't just mean building big complex C/C++ engines, or even analytical engines, to use the data. Remember that a significant part of public outreach is ...
- 121k
12
votes
Does NASA use any type of office/groupware software and which is that?
NASA's standard desktop office computer configuration is Windows 10 with Microsoft Office. This software is provided agency-wide by the NASA Shared Services Center (NSSC). Here is an excerpt from the ...
- 178k
11
votes
Accepted
What does the software quality process for NASA's SLS look like?
I have retrieved via FOIA request the "Space Launch System Program (SLSP), Flight Software Application, Software Assurance Plan (SAP)". It is the core document describing the software development ...
- 5,271
11
votes
Does the Voyager team use a wrapper (Fortran(77?) to Python) to transmit current commands?
I didn't work on Voyager, but can tell you that deep-space missions tend to retain the original ground hardware, software, language, and build environment, both for continuity/safety as well as budget ...
- 381
11
votes
How does a command sent to a rocket or rover look like?
Most remotely controlled spacecraft and rovers do not use text-based commands. Instead, each command has a unique identifier, a command-specific data structure that contains data specific to that ...
- 73.2k
10
votes
Accepted
Is the software running on any existing or decommissioned space probes available for download?
NASA just released their 2017-2018 software catalog which lists many different types of software used by NASA. Access requirements and restrictions are as follows:
General Public Release—For codes ...
- 1,150
10
votes
Accepted
What caused New Horizon's so-called "40-year glitch"?
I found a bit more detail by googling for "New Horizons Anomaly Review Board Report". The best writeup was from here.
By 4 p.m., the mission's Anomaly Review Board had convened to be
briefed on ...
- 178k
Only top scored, non community-wiki answers of a minimum length are eligible