Do people have a particular attachment to the power architecture?
Yes, it is the best commercially viable ISA on the market for servers.
The Last POWER1 CPU on Mars Is Dead
121–130 of 145 posts
Re: The Last POWER1 CPU on Mars Is Dead
#122Why does it have SPARC architecture CPUs as well I wonder? Any guesses?
Re: The Last POWER1 CPU on Mars Is Dead
#123Earlier quoted context omitted.
> 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…
You can't synchronize the stations because simultaneity does not exist due to relativity. There will always be reference frames where one station signals before another.
Re: The Last POWER1 CPU on Mars Is Dead
#124I like to think of those more recent PPC Mars machines as Nintendo GameCubes with robotic arms and eyes. Same G3 processor family, afterall.
Well, at least they should be able to browse the web with the G3 version of TenFourFox. ;)
Re: The Last POWER1 CPU on Mars Is Dead
#125Earlier quoted context omitted.
Nope, Gregorian Calendar and Solar calendar don't have exactly same days (although it is very small), and thus the different leap years. Martian days being around 37 min longer, you might need more leap days though.
Leap days are caused by one revolution not being a whole number of rotations. The weird thing with Mars would be that if you contact someone at 5pm local today it might not be okay to call them at the same time tomorrow, because they would clock in 37 minutes later.
> Leap days are caused by one revolution not being a whole number of rotations.
Right, a whole 24 hours ;)
> if you contact someone at 5pm local today it might not be okay to call them at the same time tomorrow, because they would clock in 37 minutes later.
That is assuming that people on mars will have 24hr and 37 min clocks instead of 24hr.
The only thing that will be different on Mars would be that the sunrise will change 37 minutes everyday. Weird indeed.
Re: The Last POWER1 CPU on Mars Is Dead
#126Might be O/T, but I found it really interesting how they mention "5,352 Martian solar days". Do we humans have plans in the pipeline for a universal time standard we can use wherever we are? Something that is a little more useful than "seconds since UNIX epoch" but something a little less terrestrial than UTC? Or is time going to be based wherever we land or travel (e.g. divide up Mars into time zones upon colonizati…
According to relativity, you cannot get two different observers to agree on any kind of universal time, or even the order in which two events occurred. Observer A says that event X happened before Y. Observer B says that event Y happened before X. And they're both right from their POV.
Can't it just be solved with a equation ? If you know how fast time runs relative to yours !?
Re: The Last POWER1 CPU on Mars Is Dead
#127Might be O/T, but I found it really interesting how they mention "5,352 Martian solar days". Do we humans have plans in the pipeline for a universal time standard we can use wherever we are? Something that is a little more useful than "seconds since UNIX epoch" but something a little less terrestrial than UTC? Or is time going to be based wherever we land or travel (e.g. divide up Mars into time zones upon colonizati…
Time is not homogeneous accross the universe anyway, so what would be the absolute referential ? Best we can do is pick an arbitrary one, and then create algos and tables to convert from that.
We already do that with UTC, and even with something that simple, it gets hard: politics gets in play, and we have to reajust our time slices with leap periods regularly.
Re: The Last POWER1 CPU on Mars Is Dead
#128Earlier quoted context omitted.
I know that system clock drift can be bounded to milliseconds using an atomic clock or GPS receiver, but I didn't know whether we could overcome synchronization difficulties when speed-of-light differences are significant. I thought we could package some coordinate reference system, directional travel metadata (I'm traveling 0.000002c this way), and current system clock time, and synchronize that way. Fantasy use cas…
There is Barycentric Coordinate Time which is the time from a hypothetical clock at rest at the centre of mass of the Solar System. This is easier to calculate across spacecraft than an Earth-centric time would be. However, because it's outside of Earth's gravity well it ticks slightly faster than Earth time.
If it was at rest at the centre of mass of the Solar System wouldn't it be in the sun's gravity well?
Edit - I looked it up - it's "a clock that performs exactly the same movements as the Solar system but is outside the system's gravity well."
Re: The Last POWER1 CPU on Mars Is Dead
#129Might be O/T, but I found it really interesting how they mention "5,352 Martian solar days". Do we humans have plans in the pipeline for a universal time standard we can use wherever we are? Something that is a little more useful than "seconds since UNIX epoch" but something a little less terrestrial than UTC? Or is time going to be based wherever we land or travel (e.g. divide up Mars into time zones upon colonizati…
One of the proposals for Mars in fiction was to use Earth 24 hours and then stop the clock for those additional 30 or 40 minutes Mars day has. Anyway, I suspect that humans will tend to use the most common standard, meaning some legacy standard and in case of time it is likely would be UNIX time. 110 volts AC too probably :)
Re: The Last POWER1 CPU on Mars Is Dead
#130Why does it have SPARC architecture CPUs as well I wonder? Any guesses?
It's unclear whether you're asking why they have both SPARC and PPC chips, or what the SPARCs are used for.
For the former, different contractors for the features, with some contractors preferring RHPPC and other RHSPARC?
For the latter, one SPARCs controlled the thrusters and descent stage, the other controls the movement (it's the main chip of the motor controller).