111–120 of 145 posts
Do people have a particular attachment to the power architecture?
There's still a reasonable PPC Mac/Amiga hobbyist community, many of whom will tell you about how much purer PowerPC is compared to the evil ugly x86. As someone who does PPC Linux kernel work the pragmatic part of me would like to drop support for a lot of these older machines, but as long as the machines are still actively used the support gets maintained.
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There's still a reasonable PPC Mac/Amiga hobbyist community, many of whom will tell you about how much purer PowerPC is compared to the evil ugly x86. As someone who does PPC Linux kernel work the pragmatic part of me would like to drop support for a lot of these older machines, but as long as the machines are still actively used the support gets maintained.
There are newer PPCs as well, like the Talon motherboards.
(Disclosure: I work for IBM.)
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What a coincidence, I'm working on the core flight system project right now, which includes an implementation of CCSDS File Delivery Protocol. You might be happy to know that project is still very much alive within NASA (you were probably already aware).
Fairly off topic ;), but any idea if SQLite is used on any of the rovers, spacecraft, etc? Mostly from idle curiosity. Was wondering a few days ago and guessing "probably yes", but no idea who to ask. So, taking the opportunity (heh) now. :)
Are these powered by battery or solar, or both?
Newer rovers like curiosity are using radioisotope generators which should last a much longer time.
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> Do we humans have plans in the pipeline for a universal time standard we can use wherever we are? This fundamentally cannot exist. Any "universal" system would drift for observers on different planets. Having different times in New York and New Delhi isn't the worst right now; doing a calendar look-up for the time on Mars isn't as neat. But given we won't have real-time communication, it isn't as big of a problem e…
It doesn't appear to be impossible. Setup a transmitter at earth which emits a signal at uniform intervals containing current time (seconds since kanye west's marriage). An observer can then deduce current time if it knows where it is. I don't think relativistic dilation would effect this method. With multiple such emitters synchronized with each other, one might even be able to 'triangulate' the current time. (I hav…
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It doesn't appear to be impossible. Setup a transmitter at earth which emits a signal at uniform intervals containing current time (seconds since kanye west's marriage). An observer can then deduce current time if it knows where it is. I don't think relativistic dilation would effect this method. With multiple such emitters synchronized with each other, one might even be able to 'triangulate' the current time. (I hav…
I'm not sure I see what you'd be gaining there, though. You'd be, at great expense, trading one basket of headaches - clocks not staying in sync - for another one: one second measuring a different length of time on each planet.
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No. You would have to observe the planet from your position and that observation changes based on how you move relative to the planet. The whole of SRT and GRT work in such a way that no general clock synchronization can ever exist for observers in different frames of reference. If you take a reference with you on a journey through the solar system, that reference will stay accurate for an observer travelling with it…
What I had in mind is, you can observe your planet's position and velocity (relative e.g. to center/rotation of the galaxy), and the target planet's relative position and velocity, and use both to translate the observations into virtual "stationary" observations... And "unit of time" would be defined as 1/n of one planetary/galactic revolution, so every observer would be able to calculate their own "galactic time" in…
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Fairly off topic ;), but any idea if SQLite is used on any of the rovers, spacecraft, etc? Mostly from idle curiosity. Was wondering a few days ago and guessing "probably yes", but no idea who to ask. So, taking the opportunity (heh) now. :)
The small parts of the Mars Rovers (MER) I worked on or worked with didn’t use SQLite. It was too early in SQLite’s history for it to be used on MER. MER also used VxWorks which probably didn’t have a lot in the way of POSIX support at the time. I remember other devs telling me the fun they had supporting 1553 bus on “such a new RTOS”. Wikipedia say MSL used VxWorks as well. I’d have to ask a buddy still doing Missio…
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Fairly off topic ;), but any idea if SQLite is used on any of the rovers, spacecraft, etc? Mostly from idle curiosity. Was wondering a few days ago and guessing "probably yes", but no idea who to ask. So, taking the opportunity (heh) now. :)
Not a Mars spacecraft, but SQLite has definitely been used on some CubeSat missions in LEO. I know because I'm the one who did it. :-)
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There's still a reasonable PPC Mac/Amiga hobbyist community, many of whom will tell you about how much purer PowerPC is compared to the evil ugly x86. As someone who does PPC Linux kernel work the pragmatic part of me would like to drop support for a lot of these older machines, but as long as the machines are still actively used the support gets maintained.
There are newer PPCs as well, like the Talon motherboards.