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86 votes
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What makes (or at least made) 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 ...
Morgloz's user avatar
  • 861
62 votes

What makes (or at least made) 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) ...
David Hammen's user avatar
58 votes
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Why is the James Webb Space Telescope's data storage space so small?

Best Technology Available By late 2002, SSDs had just reached ~80 GB capacities. Of course, JWST is not going to take a product which has never seen enterprise deployment, and plonk it into \$2 ...
Lawnmower Man's user avatar
47 votes

What was the first programming language in space?

(I'm interpreting the question as "what programming language was the first spacecraft software written in?", per discussion in comments above.) This will depend on your definitions of "...
Russell Borogove's user avatar
47 votes
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Why did NASA set up a computing facility in Bermuda in the Mercury epoch?

Bermuda was one of the tracking stations for the Mercury program. Bermuda was critical as it had a good view of much of the ascent trajectory. In this image, all of the tracking stations are shown ...
Hobbes's user avatar
  • 128k
41 votes

Unix Epoch in International Space Station

POSIX time doesn't include leap seconds, and is not implemented the same way in every UNIX, so it routinely gets inconsistent for several seconds every couple of years. It is not a high-precision ...
Ryan C's user avatar
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37 votes
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Orbital Supercomputer for Martian and Outer Planet Computing

They act as a massive supercomputer I think you massively underestimate how massive a massive supercomputer is, and most importantly, how massive both the power requirements and the cooling ...
Jörg W Mittag's user avatar
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 ...
Hobbes's user avatar
  • 128k
33 votes

Why is the James Webb Space Telescope's data storage space so small?

Space hardware almost always is pretty archaic technology. The problem is the long lead time coupled with the need to certify it for flight. It wasn't archaic when it was engineered. The JWT was ...
Loren Pechtel's user avatar
32 votes

Unix Epoch in International Space Station

No. Computer clocks are inaccurate. They rely on constant corrections to maintain the correct time. Since their inaccuracy is much bigger than the time speed difference between earth and the ISS, it ...
Antzi's user avatar
  • 12.6k
31 votes

The Martian: Does it really take a supercomputer to calculate spaceflight maneuvers?

Well, developing low-thrust trajectories does take more computation than impulsive trajectories (e.g. like Voyager, which was done with rather primitive computers). You have no choice but to run many ...
Mark Adler's user avatar
  • 58.2k
28 votes

Unix Epoch in International Space Station

It doesn’t yet matter for most practical purposes. The slowdown from faster motion and speedup from a weaker gravitational field partly cancel out, and the net effect is that time on the ISS is only 0....
Mike Scott's user avatar
25 votes

How would blockchain be integrated into spaceflight? Have any methods been proposed yet?

Blockchain is a very poor solution to a specific problem: achieving ledger consensus among a large number of agents when there is substantial incentive to corrupt the record, and the entries in the ...
Russell Borogove's user avatar
25 votes
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What space applications, projects and agencies are using the Ada programming language?

What other space applications, projects and agencies are using the Ada programming language? In the US, old stuff such as the Delta rockets, the Atlas rockets, and the TDRSS ground terminal (but this ...
David Hammen's user avatar
22 votes

What makes (or at least made) 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 ...
Machavity's user avatar
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21 votes

How did the Apollo guidance computer handle parity bit errors?

1. How did the Apollo guidance computer handle parity bit errors? According to Apollo 15 Hardware by Delco Electronics, Parity Alarm Occurs if any accessed word in fixed or erasable memory ...
DrSheldon's user avatar
  • 48k
20 votes

The Martian: Does it really take a supercomputer to calculate spaceflight maneuvers?

Calculating an energy-optimal orbit for a simple thing like Earth->Mars is no big deal. Even using low-thrust engines doesn't add much to it. It would be tedious but you could do it on a calculator. ...
Loren Pechtel's user avatar
18 votes

How many petaflops does it take to land on the moon? What does Artemis need with an Aitken?

All that computing power is not dedicated to the Artemis project. As you quote in the body of your question, The new supercomputer will be used by more than 1,500 scientists and engineers from ...
Nuclear Hoagie's user avatar
17 votes

What makes (or at least made) 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, ...
Cees Timmerman's user avatar
17 votes

Orbital Supercomputer for Martian and Outer Planet Computing

Mbps deep space data rates are becoming more common these days. Data corruption is not much of a problem with 21st century forward and backward error correction. And then, what problem are you tying ...
John Doty's user avatar
  • 3,364
16 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'...
RickNZ's user avatar
  • 556
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. ...
Ludo's user avatar
  • 14.4k
14 votes

What was the first programming language in space?

The first vessel that crossed the Kármán line and reached space - the German V-2 rocket - utilized a program for its analog computer, implemented as a rotating irregular disk of specific shape, with ...
SF.'s user avatar
  • 55k
14 votes

How did the Apollo guidance computer handle parity bit errors?

What a fascinatingly obscure question :-) It took some digging, so perhaps someone who's actually seen an AGC might know better: The parity bit was used to verify that data transferred correctly from ...
Michael Stachowsky's user avatar
13 votes
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What is a "Lear Processor" and how did it work?

It's an algorithm to speed up certain matrix operations, not a piece of hardware. It appears that the algorithm was first invented by William M. Lear for the LM guidance computer, as explained in @...
DrSheldon's user avatar
  • 48k
12 votes
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Why would Space Cube 1.0 have so many On-Orbit Upsets over South America?

The lower map appears to show the South Atlantic Anomaly (SAA), an area where the inner Van Allen radiation belt comes closest to the surface of the Earth. From the linked article: The effect is ...
Organic Marble's user avatar
12 votes
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What are some specific examples of the calculations human "computers" did for the Mercury space program?

(This is adapted from my question/answer at Day-to-day tasks of human computers, ala Hidden Figures movie - History of Science and Mathematics Stack Exchange) I was also fascinated by the film Hidden ...
nealmcb's user avatar
  • 711
11 votes

SAR image processing

SAR (Synthetic Aperture RADAR) data is streamed to Earth-based stations for processing. x86 processors can and are used for deconvolving that mass of data. The processing load is high, but a modern ...
C. Towne Springer's user avatar
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 ...
stevegt's user avatar
  • 391

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