4 ms·
Actually, I think it could last for millennia as built. Just not the full 89,000,000 years as mentioned. Even if you ditch the theory, there's a good chance thi
by szczys 8y ago
Actually, I think it could last for millennia as built. Just not the full 89,000,000 years as mentioned. Even if you ditch the theory, there's a good chance this will keep running as built for several decades and that's pretty crazy. Makes me want to build one and let it run.
- dekhn 8y agovoyager is a 40 year old spacecraft which still runs. A terrestrial magnetic bearing running for decades is not crazy.
- hn_throwaway_99 8y agoVoyager is also powered by big balls of plutonium.
- dekhn 8y agothat wasn't my point. My point was that mechanical things can move for long periods of time, there's nothing crazy about that. https://en.wikipedia.org/wiki/Oxford_Electric_Bell https://en.wikipedia.org/wiki/Oxford_Electric_Bell https://en.wikipedia.org/wiki/Beverly_Clock https://en.wikipedia.org/wiki/Beverly_Clock https://en.wikipedia.org/wiki/Atmos_clock https://en.wikipedia.org/wiki/Atmos_clock
- MrEldritch 8y agoThe mechanical aspect of this has nothing whatsoever to do with why it wouldn't last for millennia - it's the fact that it's coupled to a resistive load that will dissipate power from the battery much faster than the motor itself uses, and act to brake it over time as the battery voltage drops.
- alanbernstein 8y agoAre there mechanical components on Voyager?
- amelius 8y agoAnd what is their duty cycle?
- dekhn 8y agoJPL knows. BUt more importantly, when the original thrusters broke after 37 years, they were able to switch the backups and it worked fine. To me, remotely fixing a space probe beats a spinning magnetic bearing on earth for amazing engineering any day.
- dekhn 8y agohttps://www.newscientist.com/article/2155460-nasa-fires-voyager-1s-engines-for-the-first-time-in-37-years/ https://www.newscientist.com/article/2155460-nasa-fires-voya... Also (from https://voyager.jpl.nasa.gov/mission/did-you-know/ https://voyager.jpl.nasa.gov/mission/did-you-know/): The electronics and heaters aboard each nearly one-ton Voyager spacecraft can operate on only 400 watts of power, or roughly one-fourth that used by an average residential home in the western United States. A set of small thrusters provides Voyager with the capability for attitude control and trajectory correction. Each of these tiny assemblies has a thrust of only three ounces. In the absence of friction, on a level road, it would take nearly six hours to accelerate a large car up to a speed of 48 km/h (30 mph) using one of the thrusters. The Voyager scan platform can be moved about two axes of rotation. A thumb-sized motor in the gear train drive assembly (which turns 9000 revolutions for each single revolution of the scan platform) will have rotated five million revolutions from launch through the Neptune encounter. This is equivalent to the number of automobile crankshaft revolutions during a trip of 2725 km (1700 mi), about the distance from Boston,MA to Dallas,TX. The Voyager gyroscopes can detect spacecraft angular motion as little as one ten-thousandth of a degree.
- rootusrootus 8y agoThey are only claiming 89,000 years, not 89 million. But yeah, probably a few decades is plausible, the battery isn't going to last thousands of years.
- caf 8y agoI do wonder how long you could engineer a capacitor to last, though - given you have little constraint on its physical size.
- scottlocklin 8y agoThe magnet is the weak link. I'm pretty sure the battery will last longer.